TRANSITION METAL COMPOUND

COMPOSE METALLIQUE DE TRANSITION

English Abstract

The present invention relates to a compound with the general formula (I):
LnAmMXk, in which L is a borata benzene ligand of the general formula (II), in
which the radicals R are identical or different and are a hydrogen atom or a
C1-C10-carbon-containing group, A corresponds to a .pi.-ligand such as
cyclopentadienyl, M is a metal of group IVb of the periodic system of
elements, and X are identical or different and are a hydrogen atom, a C1-C40-
carbon-containing group, an OH group, a halogen atom or NR22, n is a whole
number 1 or 2, m is a whole number 0 or 1 and k is a whole number from 1 to 3,
the sum of n+m+k being 3 or 4. The present invention also relates to a process
for the preparation of the transition metal compound and the use thereof as
catalyst constituent when preparing polyolefins.

French Abstract

La présente invention concerne un composé de la formule générale (I): L¿n?A¿m?MX¿k?, dans laquelle L représente un ligand boratabenzene de la formule générale (II), dans laquelle les radicaux R sont identiques ou différents et représentent un atome d'hydrogène ou un groupe contenant 1 à 10 atomes de carbone, A correspond à un ligand .pi. tel qu'un cyclopentadiényle, M représente un métal du groupe IVb de la classification périodique des éléments, et les radicaux X sont identiques ou différents et représentent un atome d'hydrogène, un groupe contenant 1 à 40 atomes de carbone, un groupe OH, un atome d'halogène ou bien NR¿2??2¿, n est un nombre entier pouvant être 1 ou 2, m est un nombre entier pouvant être 0 ou 1 et k est un nombre entier pouvant aller de 1 à 3, la somme n+m+k étant égale à 3 ou 4. La présente invention concerne également un procédé de préparation de ce composé métallique de transition et son utilisation comme constituant catalyseur lors de la préparation de polyoléfine.

Claims

- 26 -

Claims

1. A compound having the formula I

LnAmMXk (I),

where L is a boratabenzene ligand of the formula II


Image



where the radicals R are identical or different and
are each a hydrogen atom, a C1-C10-group such as a
C1-C10-alkyl group or a C6-C10-aryl group and two
adjacent radicals R together with the atoms
connecting them can form a ring system, and Y is a
hydrogen atom, a C1-C10-group such as a C1-C10-alkyl
group or a C6-C10-aryl group, a halogen atom, an NR22
or PR22 radical, where R2 is a halogen atom, a C1-C10-group
such as a C1-C10-alkyl group or a C6-C10-aryl
group,
A is a .pi.-ligand such as cyclopentadienyl which can
be either substituted or unsubstituted and adjacent
substituents on the cyclopentadienyl ligand can form
a ring,
M is a metal of group IVb of the Periodic Table of
the Elements and
X are identical or different and are each a hydrogen
atom, a C1-C40-group such as a C1-C20-alkyl group, a
C1-C10-alkoxy group, a C6-C20-aryl group,
C2-C12-alkenyl group, a C7-C40-arylalkyl group, a
C7-C40-alkylaryl group, an OH group, a halogen atom or NR2 2,
n is 1 or 2,
m is 0 or 1 and
k is an integer from 1 to 3,




- 27 -

where the sum of n+m+k is 3 or 4.

2. A compound as claimed in claim 1 in which M is an
element of group IVb of the Periodic Table of the
Elements, in particular zirconium.

3. A compound as claimed in claim 1 or 2 in which the
radicals R are identical and are each a hydrogen
atom, a C1- C4 -alkyl group or a C6-C10-aryl group and
Y is a C1-C4-alkyl group or NR22, where R2 is a
C1-C4-alkyl group.

4. A compound as claimed in one or more of claims 1 to
4 in which A is a substituted cyclopentadienyl

5. A compound as claimed in one or more of claims 1 to
5 in which X is NR22, where R2 is a C1-C4-alkyl group,
a C6-C10-aryl group or a halogen atom, in particular
chlorine.

6. A compound as claimed in one or more of claims 1 to
6, wherein m = 0 or 1 when n = 1 and m = 0 when
n = 2.

7. A compound as claimed in one or more of claims 1 to
7, wherein L and A are joined to one another by
means of a bridge and L are identical or different
when n is 2.

8. A process for preparing a compound having the
formula (I) as claimed in any of claims 1 to 7,
wherein a compound having the formula (III)


- 28 -




Image



reacts with MX1, where 1 is an integer from 3 to 5.

9. A process for preparing a compound having the
formula (I) as claimed in any of claims 1 to 7,
wherein a compound having the formula (v)



Image



reacts with A-M'1.

10. A process for preparing a compound having the
formula (I) as claimed in any of claims 1 to 7,
wherein a compound having the formula (VII)




Image




reacts with AMX1-1.



- 29 -
11. The use of the compound having the formula I as
claimed in any of claims 1 to 7 as a catalyst
component in the polymerization of olefins.

12. A catalyst comprising a) at least one compound as
claimed in one or more of claims 1 to 7 and b) at
least one cocatalyst.

13. A process for preparing a polyolefin by
polymerization of one or more olefins in the presence
of a compound as claimed in one or more of
claims 1 to 7.

14. A polyolefin able to be prepared by the process as
claimed in claim 13.

Description

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Description

Transition metal compound

The pre8ent invention relates to a tra~ition metal
compound and a process for it~ preparation and also to
its u-~e as a catalyst component in the preparation of
polyolef in~ .

The literature di6clo~es the preparation of polyolefins
u8ing soluble metallocene compounds in combination with
aluminox~ne~ or other cocatalyst~ w~i~h, owing to their
Lewi~ acidity, can convert ~he neutral tran~ition metal
compound into a cation and stabilize it (EP-A-129 368,
EP-A-351 392).

Me~allocenes and semisand~ich compound~ are of great
interest not only for th~ polymerization or
oligomerization of olefins. They can also be used as
hydro~enation, epo~idation, i~omerization and C-C
coupling catalyst~ ~Chem. Rev. 1992, 92, 965-994).
WO 96/23004 di~clo6es certain boron-containing transition
metal compounds.

of great interest are tran~ition metal compounds which
have xufficient activity in re~pect of the abovedescribed
~ield~ of application.

It is an object of the present invention to provide a
transition metal compound and an economical and environ-
mentally friendly process for i~s preparation.

This object is achieved by a compound having the formulaI

LnAmMxk ( I )

where ~ is a boratabenzen~ ligand of the formula II

- -
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95/F ~13 K WO - 2 -


R R
R ~ ~_y
R R (Il)

whe~e ~he radic~l~ R are identical or dif$erent and are
each a hydrogen atom, a Cl-C20-group, preferably a C~-C10-
group ~uch as a Cl-C~0-alkyl group or a C6-Cl0-aryl group,
and two adja~ent radicals R together with the atoms
connecting them can form a ring ~y~tem, and Y is a
hydrogen atom, a Cl-C20-group, preferably a C~-C~0-group
~uch a~ a C~-C10-alkyl group or a C6-C10- aryl group, a
~alogen atom, an oR2, SR2, NR22 or PR22 radical, where R2 i~
a halogen atom, a C1-C1O-group such a~ a C~-C,~-alkyl
1~ group, preferably a C2-C~-alkyl grOup, or a C6-C1O-aryl
group and two radical-~ R2 can form a ring ~ystem,
A is a ~ ligand such a~ cyclopentadienyl which can be
either substituted or un~ub~tituted and adjacent sub~
tuent~ on the cyclopentadienyl ligand can form a ring,
M is a metal of group IVb of the Periodic Table of the
Elements and
X are identical or different and are eac~ a hydrogen
atom, a C1-C40-~roup ~uch as a cl-C20-alkyl group, a ~-C~0-
alkoxy group, a C~-C20-aryl group, a C2-Cl2-alkenyl group,
a C,-C~0-arylalkyl group, a C7-C40-alkylaryl group, an OH
group, a halogen atom or ~R22,
n is 1 or 2,
m is 0 or 1 and
k is an integer from 1 to ~,
2s where the sum of n+m~k is 3 ox 4.

L and A can be joined to one another by mean~ of a
bridge. When n is 2, ~ can be identical or dlfferent

The ~ridge is pre~erably

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95/F313 K WO - 3 -
~ ~ RX ' , Rx RX

2 - ~2 ~2 --C C--

RY , F~l~ RY ' Rr RY

~ Rs

--O--I Z o-- C
I
RY R~ RY Rr R~


RX RX ~X f~ TX RX
O ~-- - C--~ C C--C--
RY ' RY RY ' RY R~ RY

~BRX, ~AIR~, -Ge-, -O-, -S-, ~SO, >SOz, ~NRX, ~CO, ~pRx or
~P(O)RX, where Rx and RY are identical or di~ferent and
are each a hydrogen atom, a halogen atom or a Cl-C,O-group
~uch as a C1-C20-alkyl group, a Cl-C1O-fluoroalkyl group, a
Cl-C1O-alkoxy group, a C~-Cl,-aryl group, a C6-C1O-fluoroaryl
group, a C6-C~O-aryloxy group, a C2-C1O-alkenyl group, a
C7-C~O-arylalkyl group, a C~-C40-alkylaryl group or a C~-C~O-
arylalkenyl group and M~ i~ silicon, germani~m or ~in.

Examples of bridges are groups (M2RXRY)y~ where Ma i~
carbon, silicon, germanium or tin and Rx and RY are
identical or different and are each a Cl-C20-hydrocarbon
group such as Cl-C~O-alkyl or c6-C~4-aryl and y is 1 Qr 2,
e.g. CH2, CH2CH2, CH ( CH3 ) CH2, C ( CH3 ) ( C6H5 ), C ( C6H5 )
CH(C~H~)C(CH3)z~ C(CH3)2, C(CH3) (C6H5), C(C6H5)2~ (CH3)2$i~
~CH3) 2Ge, tCH3) 2Sn, (C6H5) 2Si, (C6Hs) (CH3) Si, (C6H5) 2Ge,
~C6H5)2Sn, (CH2)~Si, CH2$i(CH3)z~ o-C6H4 or 2,2'-(C6H4)2

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95/F 313 K WO - 4 ~
The pre8ent invention accordingly provides a tran~ition
metal compound which contains as a ligand at lea~t one
substituted or unQubxtituted boratabenzene group and is
described by the formula I.

A preferred ~mho~ nt of the invention is a compound in
whic~ M i~ an element of group IVb of the Periodic Table
of the Elements, in parti~ular zirconium.

A preferred embo~;me~t of the invention i8 a compound in
which the radical~ R are identical and are ea~h a hydro-
gen atom, a Cl- C4 - alkyl group or ~ C6 - C10 - aryl group and Y
i~ a Cl-C~-alkyl group or NR2Z, where R2 is a C -C4-alkyl
group, preferably a Cz-C4-alkyl group.

A preferred embodiment of the in~ention is a compound in
which A is a substituted cyclopentadienyl ligand.

A preferred embodi~ent of the invention is a compound in
which X is Cl-C1O-alkyl or NRa2, where R2 i-~ a Cl-C4-alkyl
group, a C6-C~O-aryl group or a halogen acom, in
particular chlorine.

A preferred embodiment of the invention ie a compound in
which m - O or 1 when n = 1 and m - O when n ~ 2.

A i~ preferably a ~-ligand ~uch as cyclopentadienyl,
indenyl or fluore~yl, which can each be either
substituted or unsu~tituted.

~-~igands are preferably an u~ub~tituted cyclopenta-
dienyl group or sub~tituted cyclopentadienyl group whichpreferably bear one or more Cl-C~O-hydrocarbon radicals a3
sub~tituents, e.g. 2-methylcyclopentadienyl, methyl-tert-
butylcyclopentadienyl, tert-butylcyclopentadienyl,
i~opropylcyclopentadienyl, di~ethylcyclopentadie~yl,
trimethylethylcyclopent~;enyl, 5-phenylcyclopentadienyl,
diphenylcyclopentadienyl, ~n~Anyl, 2-me~hyli n~enyl, ~-
ethylin~nyl, 3-methylindenyl, 3-tert-butylin~yl, 2-


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95/F 313 K WO - 5 -
methyl-4-phenylindenyl, 2-ethyl-4-phenylindenyl, 2-
methyl-4-naphthylinde~yl, 2-methyl-4-i~opropylindenyl,
benzlnfl~nyl, 2-methyl-4,5-benzindenyl, 2-methyl-a-ace-
naphthindenyl, ~-methyl-4,6-dii~opropylindenyl,
~luorenyl, 4-methylfluorenyl or 2,7-di-tert-butyl-
fluorenyl.

Particular preference i~ given to compound~ of the
formula I in which M i~ zirconium and X are identical and
are each a halogen atom, in particular chlorine.

Particular preference is given to compound~ of ~he
formula I i~ which L iQ a boratabenzene ligand of the
formula II and the radical~ R are preferably identical
and are each a hydrogen atom ~nd Y is preferably a C1-C~-
alkyl group ~uch aq methyl, ethyl, propyl, isopropyl or
butyl, or NRa2 in which R2 i~ a Cl-C,-alkyl group such a~
methyl, ethyl, propyl, isopropyl or butyl. When m i~ 1,
A is preferably a cyclopentadienyl ligand s~ch as cyclo-
pentadienyl, methylcyclopentadienyl, pentamethylcyclo-
pentadienyl or indenyl. Pre~erence i-~ al~o given to
compounds of the formula I in which X are identical and
are each a Cl-C4-alkyl group, in particular methyl, or a
C7-C~O-alkylaryl group, in particular benzyl, or a halogen
atom, in particular ch~orine, and n i~ 1 or 2 and m is O
or 1 when n i~ 1 and m is O when n is 2 and the ~um of
n+m+k can be 3 or 4.

Example~ of transition metal compound~ of the invention
are: -

(l-methylboratabenzene)~pentamethylcyclopentadienyl)-
zirconium dichloride
(1-butylboratabenzene)(pentamethylcyclopentadienyl)-
zirconium dichloride
(l-methylbora~benzene)(pentamethylcyclopentadien~l)-
dimethylzirconium
(l-butylboratabenzene)(pentamethylcyclopentadienyl)-
dibenzylzirconium

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95/F 313 K WO - 6 -

[1-(dimethylamino)boratabenzene](pentamethylcyclo-
pentadienyl)-zirconium dichloride
[1-(diethylamino)boratabenzene](cyclopentadienyl)-
zirconium dichloride
[l-(dimethylamino)boratabenze~e](pentamethylcyclo-
pentadienyl)dimethylzirconium
~1-(diethylamino)boratabenzene](cyclopentadienyl)di-
benzylzirconium
(1-methylbora~abenzene)(cyclopentadienyl)zirconium
dichloride
(l-methylborat~h~n~ene)(methylcyclopentadienyl) 2 irconium
dichloride
(1-methylboratabenzene)(cyclopentadienyl)dimethylzir-
conium
(1-methylboratabenzene)(methylcyclopentadienyl)di-
benzylzirconium
bi~ methylboratabenzene)zirconium dichloride
bis(1-methylboratabenzene)dimethylzirconium
bis(l-methylborata~enzene)hafnium dichloride
bis(l-methylboratabenzene)dibenzylzirconium
(l-methylboratabenzene)zirconiumtrichloride
(1-ethylboratabenzene)zirconium trichloride
(l-methylboratabenzene)(indenyl)zirconium dichloride
(l-~ethylboratabenzene)(indenyl)dimethyl zirconium
(l-me~hylboratabenzene)(indenyl)dibenzyl zirconium
[1-(dimethylamino)boratabenzene~(indenyl)zirconium
dichloride
(1-methylboratabenzene)(pentamethylcyclopentadienyl)-
titanium dichloride
(1-methylbor~tabenzene)(cyclopentadienyl)titanium
dichloride
[1-(dimethylamino)boratabenzene](cyclopentadienyl)-
titanium chloride
bi~(l-methylboratabenzsne)titanium dichloride
bi~ methylboratabenzene)titanium chloride
(1-methylboratabenzene)titanium ~richloride
(1-methylboratabenzene)titanium dichloride
(l-methylboratabenzene)(indenyl)titanium dichloride
~ dimethylamino)boratabenzene](indenyl)titanium

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95/F 313 K W0 - 7 -
chloride
[l-(diethylamino)boratabenzene](pentamethylcyclopenta-
dienyl~titanium dichloride
tl-(diethylamino)boratabenzene~lpentamethylcyclopenta-
dienyl)hafnium dichloride
[1-(diethylamino)boratabenzene]~pentamethylcyclopenta-
dienyl)zirconium dichloride
~1-(diethylamino)boratabenzene](pentamethylcyclopenta-
dienyl)dimethylzirconium
[1-(pyrrolidino)boratabenzene](pentamethylcyclopenta-
dienyl)zirconium dichloride
[l-(piperidino)borataben~ene](pentamethylcyclopenta-
dienyl)zirconium dichloride
tl-(pyrrolo)boratabenzene](pentamethylcyclopentadienyl)-
zirconium dichloride~1-(bi8trimethylsilylamino)boratabenzene~(pentamethyl-
cyclopentadienyl)zirconium dichloxide
tl-(diisopropylamino)boratabenzene](pentamethylcy
pe~tadienyl)zirconium dichloride
[1-(N-methylanilino)bora~Ahen7,~e](pentamethylcyclopenta-
dienyl)zirconium dichloride
[1-(diphenylamino)boratabenzene~(pentamethylcyclopenta-
dienyl)zirconium dichloride
tl-(pyrrolidino)borat~h-n7ene]~cyclopentadienyl)zirconium
dichloride
[l-(piperidino)boratabenzene](cyclopentadienyl)zirconium
dic~loride
[l-(pyrrolo)boratabenzene](cyclopentadienyl)zirconium
dichloride
[l-~bi~trimethyl~ilylamino)boratabenzene](cyclopenta-
dienyl)zirconium dichloride
[1-(diisopropylamino)boratabenzene](cyclopentadienyl)-
zirconium dichloride
[1-(N-methylanilino)boratabenzene~tcyclopen~adien~l)-
zirconium dichloridetl-(diphenylamino)~ora t aben z ene](cycl opent adienyl)-
zirconium dichloride
[l-(diphenylpho~phino) borat abenzene](pentamethylcyclo-
pentadienyl) titanium dichloride

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95/F 313 K W0 - 8 -
[l-(~iphenylphosphino)boratabenzene~(pentamethylcyclo-
pentadienyl)zirconium dichloride
~l-(diphenylphosphino)boratabenzene3(pentamethylcyclo-
pentadienyl)dimethylzirconium
S [l-(di~ethylphosphino)boratabenzene](pen~amethylcyclo-
pentadienyl)zirconium dichloride
[1-(dibutylphosphino)boratabenzene](pen~amethylcyclo-
pentadienyl)zirconium dichloride
[1-(dii~opropylphosphino)bora~abenzene](pentamethylcyclo-
pentadienyl)zirconiu~ dichloride[1-(dicyclohexylphosphino)boratabenzene](pentamethyl-
cyclopentadienyl)zirconium dichloride
[1-(diphenylpho8phino)borat~benzene](cyclopentadienyl)-
zirconium dichloride
[1-(dimethylpho~phino)boratabenzene](cyclopentadienyl)-
zirconium dichloride
[1-(dibutylphosphino)boratabenzene](cyclopentadienyl)-
zirconium dichloride
E1-(diisopropylpho~phino)boratabenzene](cyclopenta-
dienyl)zirconium dichloride[1-(dicyclohexylphoQphino)boratabenzene]( cyc lopenta-
dienyl)zirconium dichlo~ide
bis[1-(diethylamino)boratabenzene]zirconium dichloride
bistl-(diethylamino)boratabenzene]dimethylzirconium
bis[1-(pyrrolidino)boratabenzene]zirconium dichloride
bis[1-(diphenylphosphino)boratabenzene~zirconium
dichloride
bi~[l-(dimethylphosphino)boratabenzene]zirconium
dichloride
[1-(diethylamino)boratabenzene](indenyl)zirconium
dichloride
~1-(diethylamino)boratabenzene](fluorenyl)zirconium
dichloride
~l-(~e~hylboratabenzene](fluorenyl)zirconium dichloride
[l-(diethylamino)boratabenzene]titanium trichloride
~1-(diethylamino)boratabenzene] titanium dichloride
bi~[l-(diethyla~ino)boratabenzene]ti~anium chloride
ethylenebis[4~ methylboratabenzene)~zirconium
dichloride

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- 95/F 313 K W0 - ~ -
ethylenebi~[3~ methylboratabenzene)~zirconium
dichloride
ethylenebis[2-~1-methylboratabenzene)]zirconium
dichloride
ethylenebis(1-boratabenzene)]zirconium dichloride
ethylenebi~s-(1-dimethylaminoboratabenzene)~zirconium
dichloride
ethylenebi~3-(l-dimethylaminoboratabenzene)~zirconium
dichloride
ethylenebis~2-tl-dimethylaminoboratabenzene)]zirconium
dichloride
ethylenebis[4-~l-diethylami~oboratabenzene)]zirconium
dichloride
ethylenebi~[4-(l-diphenylphosphinoboratabenzene)]-
zirconium dichlorideethylenebis~4-(1-pyrrolidinoboratabenzene)]zirconium
dichloride
ethylenebi~[4~ methylboratabenzene)]titanium dichloride
ethylenebix[3~ methylboratabenzene)]titanium dichloride
ethylenebis~2-(1-methylbora~be~ene)]titanium dichloride
ethylenebis(1-boratabenzene)titanium dichloride
ethylene~(4-(1-methylboratabenzene))cyclopentadienyl~-
zirconium dich-loride
ethylene~(4-(1-~ethylboratabenzene))penta~ethylcyclo-
pentadienyl~zirconium dichlorideethylene[(4-(1-methylboratabenzene))indenyl]zirconium
dichloride
ethylene[(4-(1-~ethylboratabenzene))fluorenyl]zirconium
dichloride
3~ ethylene[(1-boratabenzene)cyclopentadienyl]zirconium
dichloride
ethyleneL(l-boratabenzene)indenyl~zirconium dichloride
ethylene[(l-boratabenzene)fluorenyl]zirconium dichloride
ethylenebis(1-methylaminoboratabenzene)]zirconium
dichloride
ethylenebis~l-phenylphosphino~oratabenzene)]zirconium
dichloride
ethylenebis(1-oxyboratabenzene)]zirconium dichloride
ethylenebi~l-thioboratabenzene)]zir~onium dichloride

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95/F 313 R WO - 10 -
dimethylsilanediylbi~4-(1-methylboratabenzene)]zirconium
dichloride
dimethyl~ilanediylbis~4-(l-dimethylaminoboratabenzene)]-
zirconium dichloride
dimethylsilanediylbiQ~4-(1-diphenylpho~phinoborata-
benzene)]zirconium dichloride
dimethylsilanediylbi~[(l methyleneboratabenzene)~-
zirconium dichloride
dimethyl~ilanediylbi~[(l-methylaminoboratabenzene)~-
zirconium dichlo~idedimethylsilanediylbis[(l-oxyboratabenzene)~zirconium
dichloride
dimethylsilanediyl[(4-(1-methylboratabenzene)) cyclopenta-
dienyl]zirconium dichloride
lS dimethylsilanediyl[(4-(1-methylboratabenzene))penta-
~ethylcyclopentadienyl]zirconium dichloride
dimethyl3ilanediyl[(4-(l-methylboratabenzene))indenyl]
zirconium dichloride
dimethylsilanediyl[(4-(l-methylborar~hen7.ene))fluorenyl]-
zirconium dichloridedimethyl~ilanediyl[(4-(l-dimethylAmjno~oratabenzene))
cyclopentadienyl]zirconium dichloride
dimethylsilanediyl[(4-(1-diphenylpho6phinolborata-
benzene))cyclopentadienyl]zirconium dichloride
dimethylsilanediyl[(3-(1-dime~hylaminoboratabenzene))-
cyclopentadienyl~zirconium dichloride
dimethylsilanediyl~(2-~l-dimethyl~minohoratabenzene))-
cyclopentadienyl]zirconium dichloride
dimethylsilanediyl[(l-methylaminoboratabenzene))cyclo-
pentadienyl]zirconium dichlorideisopropylidenyl[(4-(1-dimethylaminoboratabenzene))cyclo-
pentadienyl]zirconium dichloride
isopropylid~nylbi~[s-(l methylboratabenzene)]zirconium
dichloride ~

35 The invention provideQ a proce~ for preparing the navel
transition metal compound-~ h~ving the formula (I). The
process is illustrated by the synthesis schemes below ~or
co...~ounds of the formulae IV, v and VI. I~ these

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- 95/F 313 K WO - 11 -
~ormulae, R, Y, M and X are defined as in formulae I and
II. A i~ a li~and ~uch as cyclopentadienyl, indenyl or
fluorenyl, each of which may be either ~ubstituted or
un~u~tituted. Ml i~ a metal of main group Ia of the
Periodic Table of the ~lement~.

For example, in a proces~ for preparing a compound havi~g
the formula (I), a compound having the formula (III)
reacts wi~h MXl where 1 i~ an integer from 3 to 5.

In an alternative proce~s for preparing a compound having
the formula (I), a compound having the formul~ ~V) reacts
with A-Ml'.

In a further alternative proces~ for preparing a compound
having the formula (I), a compou~d having the formula
~III) reacts with AMX~
R~ R

~Q ~ R


~ r



~' R~--r




R

In an alternative proce~R for preparing a compound having

CA 02240452 1998-06-19

- 95~F 313 K WO - 12 -
the formula ~I), a compound having the formula (VII)
reacts with MX, where 1 is an integer from 3 to 5 and Z
is an element of group IVa of the Periodic Table of the
Element~ and R3 are identical or different and are each a
hydrogen atom, a Cl-C2D-group,- for example a Cl-C20-
hydrocarbon radical such as a C1-C20-alkyl group or a
C6-C20-aryl group, or ~wo adjacent radical~ R3 together
with the atoms connecting them can form a ring y~tem.

Preferably Z i~ ~ilicon, germanium, tin or lead and R3
are identical and are particularly preferably each a Cl-
Clc-alkyl group 8uch a~ methyl, ethyl, i~opropyl or butyl
or a C~-C1c-aryl group such a~ phenyl.

In an alternative process for preparing a compound having
the formula (I), a compound having the formula
react~ with AMX1-l
R R
R~Y
R R ZR,~ R

R R~~
R~ y
t~l ~
R R


~Y
R 11



Y
q R

~he compound~ of the formulae III and VII can be prepared

CA 02240452 1998-06-19


~ 95/F 313 K WO - 13 -
by literat~re methods (Organometallics 1995, 14, 471).
The conver~ion of the compound~ of the formula III into
the de~ired tran~ition metal complexes i~ k~own in
principle. For this purpose, the monoanion of the formula
III i~ reacted in an inert solvent with the corresponding
metal halide ~uch as zirconium tetrachloride. A is a
li~and Yuch aQ cyclopentadienyl, indenyl or fluorenyl
which can eac~ be either ~ubstituted or un~ubstituted.

S~itable solvents for the reaction are aliphatic or
aromatic ~olvents such as h~nP or toluene, ether
solvent~ such as ~etrahydrofuran or diethyl ether or
halogenated hydrocarbons such as methylene chloride or
halogenated aromatic hydrocarbons ~uch as o-dichloro-
benzene.

The invention provide~ for the use of the compound ha~ing
the formula I as a catalyst component in ~he
polymerization of olefins. The present invention
accordin~ly provides a process for preparing a polyolefin
by polymerization of one or more olefin~ in the pre~ence
2 0 of a transition metal compound of the ~ormula I . For the
purposes of the invention, the term polymeriza~ion refer~
to both homopolymerization and copolymerization.

In the process of the in~ention, preference is given to
polymerizing one or more olefin~ of the formula R'-CH=CH-
R~ where R~ and Rb are iden~ical o~ different and are eacha hydrogen atom or a ~ydrocarbon radical having from 1 to
2~ carbon atom~, in particular from 1 to 10 carbon atoms,
or Ra and Rb together with the atoms connecting them form
one or more rings. Examples of such olefi~ are l-olefins
ha~ing 1-20 carbon atom~, for example ethylene, propene,
1-butene, l-pentene, l-hexene, 4-methyl-1-pentene or l-
octene, styrene, cyclic or acyclic diene~ ~uch as 1,3-
butadiene, isoprene, 1,4-hexadiene, norbornadiene,
vinylnorbornene, s-ethylidenenorbornene or cyclic mono-
olefins such a~ nor~ornene or tetracyclododecene. In theproceyy o~ the in~ention, pre~erence is given to homopo-


CA 02240452 1998-06-19

- 95/F 313 K WO - 14 -
lymerizing ethylene or propylene or copolymerizing
ethylene with one or more acyclic 1-olefins having ~rom
3 to 20 carbon atoms, for example propylenç, and/or one
or more diene~ havi~g from 4 to 20 carbon atoms, for
5 examlple 1, 3-butadiene .

The polymerization i-~ preferably carried out at a
temperature of from -60 ~o 250~C, more preferably 20 to
70~C, particularly preferably from 50 to 20~C. The
pressure is preferably from 0.5 to 2000 bar, particularly
preferably ~rom 4 to 64 bar, very particularly prefera~ly
from 5 to 64 bar.

The polymerization can ~e carried out in solution, in
bulk, in su~pen~ion or in the gas pha-~e, continuously or
batchwise, in one or more ~tage~.

The catalyst used in the proces~ of the invention
prefera~ly comprise~ a ~ran~ition metal compound. It i~
also po~sible ~o use mix~ure~ of two or more transition
metal compound~ ~r mixture~ with metallocenes, for
example for preparing polyolefins having a broad or
multimodal molecular weight distribution.

In principle, a suitable cocatalyst in the proce~s of the
invention is any compound which, owing to i~ Lewis
acidity, can eonvert the neutral transition metal
compound in~o a cation and Qtabilize the latter ("labile
coordination"). Furthermore, the cocatalyst or the anion
formed therefrom 6hould undergo no further reactions with
the cation formed (EP-A-427 6g7). A6 cocatalyst,
pre~erence i~ given to using an aluminum compound and/or
a boron compound.

The boron compound preferably has the formula R5XNH4.xBR~,
RsxpH~-xBR6~ R53CBR6~ or BR63, where x i~ from l ~o, 4,
preferably 3, and the radical~ R5 are identical or
different, preferably identical, and are C~-Cl0-alkyl or
C6-ClR-aryl or two radicals R5 together with the atoms

CA 02240452 1998-06-19


95/F 313 R WO - 15 -
connecting them ~orm a ring, and the radicals R6 are
identical or different, preferably identical, and are
C6-Cl~-aryl which may be sub~tituted by alkyl, haloalkyl
or fluorine. In particular R5is ethyl, propyl, butyl or
phenyl and R6 is phenyl, pentafluorophènyl, 3,5-bi~-
(trifluoromethyl)phenyl, mesityl, xylyl or tolyl (EP-A-
2~ 003, EP-A-2~7 004 and EP-A-426 63~).

The cocatalyst used is preferably an all~m~ m compound
~uch as aluminoxane and/or an aluminum alkyl.

The cocataly~t used i~ particularly preferably an
aluminoxane, in particular one of the formula VIIa for
the linear type and/or the formula VIIb for ~he cyclic
type,
~ R~ -
¦ ~ R~
~ O- Al O Al ~ ~n~J)
R~ _ _ D R4



Al O ~llO)
_ _ p~2

where, in the ~ormulae VIIa and VIIb, the radicals R~ are
identical or different and are each hydr~gen or a Cl-C20-
hydrocarbon group such as a C1-Cle-alkyl group, a C6-C1,-
aryl gr~up or benzyl and p is an integer from 2 to 50,
preferably from 10 to 35.

The radical~ R4 are p~eferably identical and are hydro-
gen, methyl, isobutyl, phenyl or benzyl, particularly
preferably methyl

I~ the radical~ R4 are different, then they are
pre~erably me~hyl and hydro~en or alternati~ely methyl

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~ 95/F 313 K W0 - 16 -
and isobutyl, with hydrogen or i~obutyl preferably ~eing
present in a proportion of from 0.01 to 40~ by number (of
the radicals R4).

The methods of preparing the al~mi~o~nes are known. The
exact -~patial structure of the al~m~nox~ne~ not known
(J. Am. Chem. Soc. (1993) 115, 4971). For example, it i~
concei~able that chains and rings can joi~ to ~or~ larger
two-dimen~ional or three-dimen~ional ~tructure~.

Regardless of the method of pr~paration, all al~;nox~e
~olution~ ha~e in common a varying content of unreacted
alu~nl~ starting compound which i9 pre-~ent in free form
or a~ adduct.

It is pos~ible to preacti~ate the tran~ition metal
compound u~ing a cocatalyst, in particular an alumin-
oxane, prior to use in the polymerization reaction. Thissignificantly increa~e~ the polymerization acti~ity. The
preactivation of the transition metal compound i~
preferably carried out in ~olution. The transition metal
compound i~ here preferably di~olved in a solution of
the aluminoxane in an inert hydrocarbon. Suitable inert
hydrocarbo~ are aliphatic or aromatic hydrocarbons.
Preference i~ given to u~ing toluene.

The concentration of the al~ oxane in the solution is
in the range from about 1~ by weight to the saturation
limit, preferably from 5 to 30~ by weight, in each case
ba~ed on the total amount of solution. The transition
metal compound can be u~ed in the same concentration, ~ut
it is preferably u~ed in an amount of from 10-~ to 1 mol
per mol of aluminoxane. The preactivation time i~ from
5 minutes to 60 hours, preferably from 5 to 60 min~te~.
The preactivation is carried out at a temperature of from
-78 to 100~C, preferably from o to 70~C.

The tran~ition metal compound i8 preferably u~ed in a
concentration, ba-~ed on the ~ran~ition ~etal, of from 10~1

CA 02240452 1998-06-19

95/F 313 K W0 - 17 -
to lO-a mol, pre~erably from lO-' to 10-7 mol, of
tran~ition metal per d~ of sol~ent or per dm3 of reactor
volume. The aluminoxane is preferably used in a
concentration of from 1o-6 to 1o-l mol, preferably fro~ 10-
5 to 10-2, mol per dml of solvent or per dm~ of rea~tor
volume. The other cocatalysts mentioned are used in
approximately equimolar amount~ to the transition metal
compound. However, higher concentrations are alRo
posYible in principle.

To re~ove catalyst poisons pre~e~t in the ole~in,
purification using an aluminum compound, preferably an
al~m; ~l~m alkyl such ag trimethyla~lm;nl~m or trie~hyl-
al~minum, is advantageous. Thi~ purification can be
carried out either in the polymerization system itself or
the ole~in i~ brought into contac~ with the aluminum com-
pound and sub~equently separated off again before
addition to the polymerization system.

In the proceYs of the invention, hydrogen can be added as
a molecular weight regulator and/or to increa~e ~he
catalyst activity. This enables low molecular weight
polyolefin~ ~uch a~ waxe~ to be obtained.

In the process of the pre~ent inve~tion, the tran~ition
metal catalyst is preferably reacted with the cocataly~t
outside the polymerization reac~or in a separate step
using a suitable golvent. Application to a support can
also be carried out during thi~ procedure.

In the process of the invention, a prepolymerlzation can
be carried out with the aid o~ the transition metal
compound. For the prepolymerization, pre~erence is given
to using the (or one of the) olefin(s) used in the
polymerization.

The catalyst u~ed in the proce~s of the invention can be
~upported. Application to a support enables, for example,
the particle morphology of the polyolefin prepared to be

CA 02240452 1998-06-19

95/F 313 K W0
controlled. Here, the transition metal compound can be
f irst reacted with the ~upport and ~ub~equently wich the
cocatalys~. The cocataly~t can al~o be supported ~irst
and subsequently reacted with the tran~ition metal
co~pound. It is also possible to support t~e reaction
product of tran~ition metal compound and cocatalyst.
Suitable ~upport materials are, for example, ~ilica gel~,
aluminum oxide~, ~olid aluminoxane or other inorganic
~upport ma~erial~ such as magnesium chloride. Ano~her
lo ~uitable Qupport material i~ a polyolefin powder i~
finely di~ided form. The preparation of the ~upported
cocatalyst can be carried out, for example, as de~cribed
in EP-A-567 952.

If the polymerization is carried out as a ~uspen~ion or
solution polymeri~ation, an inert 601vent cu~tomary for
the Ziegler low-pres~ure process is used. For example,
the polymerization is carried out in an aliphatic or
cycloaliphatic hydrocarbon, for example propane, butane,
h~Y~n~, heptane, isooctane, cyclohexane, methylcyclo-
hexane. A petroleum or hydrogenated diesel oil fxactioncan al~o be u~ed. It i9 also po~sible to use toluene.
Preference i~ given to carrying out t~e polymerization in
the liquid monomer.

Before addition of the cataly~t, in particular the
-~upported catalyst system (compri~ing the tran~ition
metal compound of the invention and a ~upported
cocatalyst), another aluminum alkyl compound such as
trimethylaluminum~trie~hylaluminum~triisobutylalllm;nllm~
trioctylaluminum or i~oprenrlaluminum can be introduced
into the reactor to make the polymerization sy~te~ inert
(for example to remove catalyst poi~ons pre~ent in t~
olefin). ~iQ compound is added to the polymer~zatlo~
sy~tem in a concentration of from 100 to 0.01 mmol o~ Al
per kg of reactor conten~. Pre~erence is given, to
trii~obutylaluminum and triethylaluminum in a
concentration o~ from 10 to o.1 mmol of Al per kg of
reactor content~, This enableQ the molar Al/ml ratio to

CA 02240452 1998-06-19


95/F 313 K W0 - 19 -
be made -~mall in the synthesi~ of the ~upported catalyst
YyStem ~

If inert qolventR are used, the monomers are preferably
metered in in ga~eou~ or liquid form.

The specific tran~ition metal compound~ described in the
pre~ent invention are suita~le for the preparation of
polyolefins. The latter are suitable, in particular, for
producing shaped bodies such as filmR, plates or large
hollow bodieg (e.g. pipe~) and can al~o be used as
plasticizer and lubricant formulations, for melt adhesive
applications, coatings, seals, insulatio~, filler
compo~itions or ~ound insulation material~.

U6e of hydro~en or increasing ~he polymerization
tempera~ure make it p~ssible to obtain polyolefin~ having
15 a low molar ma6~ ~ e . g . waxe~, who~e hardnes~ or melting
point can be varied by means of the comonomer content.
Selection of the polymerization proce~ and the type(s)
of comonomer(s), ~nd also amount(s) of comonomer(~),
enable olefin copolymers having ela~tomeric properties to
be prepared, for example ethylene-propylene-1,4-hex~;ene
terpolymer~.

The following example~ illus~rate the invention.

Preparation and handling of organometallic compounds were
carried out with exclu~io~ of air and moi~ture under
protect~ve argon ga~ (Schlenk technique). All solvents
r~quired were freed of air and moi~ture ~efore u~e by
boiling for a number of hour~ over a suitable desiccant
and ~ub~equent di-~tillation under argon.

The Al/CH3 ratio in the al~m;nn~ane was de~ermined by
decomposing the sample with HzS04 and determining .the
volume of the hydrolysis gase~ formed under standard
conditions and by complexometric titration of the
aluminum in the then completely dis~olved ~ample by the

CA 02240452 1998-06-19

95/F 313 K W0 20 -
Schwarzenbach method. The compounds were characterized
using ~H-NMR, ~3C-NMR and IR spectroscopy.

Examples

Example 1

bis(l-Methylboratabenzene)zirconium dichloride

1 g of zirconium tetrachloride and 0.84 g of (1-methyl-
boratabenzene)lithium were ~u~pended in 20 ml of ~oluene
and ~tirred for three days at 100~C. The yellow
suspension obtained was filtered and the ~olvent wa~
removed under reduced pre~sure. The yellow solid o~tained
was washed with 5 ml of hexane. The yield of transition
metal compound wa~ O.B9 g (60~ of theory).
'~-NMR (CD2Cl2): 7.6, 6.6, 6.3 (each m, 5H, arom. H), 0.9
(s, 3H, CH3). Mas~ spectrum: 344 Mt~ correct
disintegration pattern.

Example 2

di(~-Chloro)tetra[h6-(1-methylboratabenzene)]dititanium

0.48 g of titanium trichloride and 0.~1 g of (1-methyl-
boratabenzene)lithium are su~pended in 10 ml of toluene
and ~tirred ~or ~hree day-~ at llO~C. The brown suspension
obtained is filtered and the filtrate is cooled to -30~C.
The bro~n solid obtained i~ wa~hed with 5 ml of h~x~n~,
giving the txansition metal compound in a yield of 60
(0.49 g).
Ma~ ~pectrum: 265 M+, correct disintegration pattern.

Example 3

~1-Methylboratabenzene)titanium trichloride

1.36 g of 1-~ethyl-6-(trimethylstannyl)-2,4-boracyclo-
h~y~nediene are dissol~ed in 10 ml of hexane and 1.1 g of

CA 02240452 1998-06-19


~ 9S/F 313 K W0 - 21 -
titanium tetrachloride are added at -10~C. After ~tirring
for 3 hour~, the red-violet ~olution i~ evaporated until
crystallization commence~ and stored for 12 hour~ at
-300C. The product is obtained in the form of deep violet
S cry~tals in a yield of 93~ (1.22 g).
H-NMR (CD2Cl2): 8.1, 7.0, 7.3 (each m, 5H, arom. H), 1.1
(8 , 3H, CH3). Ma~ spectrum: 244 Ml, correct disin-
tegration pattern.

Example 4

(1-Methylborataben 2 ene ) c yC lopentadienyltitanium
dichloride

0.57 g of cyclopentadienyltitanium trichloride are
dissolved in S ml of tetrahydrofuran and admixed at - ~ 0 ~ C
with a solution of 0.65 ~ of 1-methyl-6-(trimethyl-
stannyl)-2,4-boracyclohexanediene in 2 ml of tetrahydro-
~uran. After ~he Rolu~ion has been warmed to room
temperature, the precipitated dark green ery~tal~ are
filtered off; yield: 60~ (0.4 g).
lH-NMR (CD2Cl2): 7.8, 6.9, 5.9 ~each m, 5H, arom. H), 6.7
(m, 5H, Cp-H), 1.1 (s, 3H, CH~). Ma~s spe~trum: 274 M+,
correct diQintegration pattern.

Example 5

~ ethylboratabenzene)cyclopentadienyl~iraonium
dichloride ~

0.3 g of cyclopentadienylzirconium trichlorida is
~uQpended in 5 ml of toluene and ad~ixed at room
temperature with a solution of 0.3~ ~ of 1-methyl-6-
(trimethylsilyl)-2,4-boracyclohexanediene in 2 ~ml of
toluene. Af~er the solution has been heated for 3 hours
at ~OoC, it i~ cooled to -30~C and ~tored for 12 hour~at
thi~ temperature. Thi3 gives 0.26 g of the yellow
compound (70~).
lH-NMR (~D2C12): 7.7, 6.3, 6.~ (each m, SH, arom. H), 6.

CA 022404~2 l998-06-l9


9~/F 313 K wo - Z2 -
(m, 5H, Cp-H), 1.0 ~s, ~H, CH3). ~a~ ~pe~trum: 316 Ml,
correct disintegration pattern.

Example 6

bis(l-Methylboratabenzene)hafnium dichloride

0.32 g of hafnium tetrachloride i~ ~uspended in ~ ml of
toluene and admixed at room temperature with a solution
of 0.33 g of 1-methyl-6-(trimethylsilyl)-2,4-boracyclo-
hexanediene in 2 ml of toluene. After the ~olution ha~
been ~eated for 2 hours at 70~C, it is cooled to -30~C
and ~tored for 12 hours at thi~ temperature. ThiQ givee
0.37 g of the yellow compound (88~).
H-NMR (CD2C12): 7.6, 6.3, 6.6 (each m, 5H, arom. H), 5.8
(m, 5H, Cp-H), 1.0 (~, 3H, CH3) . Mas~ ~pectrum: 132 M+,
correct di~integration pattern.

Example 7

tl-Methylboratabenzene)(pentamethylcyclopentadienyl)-
hafnium dichloride

1.1 g of peneame~hylcyclope~tadienylhafnium trichloride
are ~uspended in 10 ml of toluene and admixed at room
temperat~re with a ~olution of 0.27 g o$ l-methylborata-
benzenelithium in 10 ml of toluene and 2 ml of dimethoxy-
ethane. After the ~olution has been heated for 3 hours at
110~C, the suspension is filtered and the filtrate is
cooled to -30~C and stored for 12 hours at this
temperature. Thi~ give~ 1. 0~ g of the pale yellow
compound (85~).
H-NMR (CD2C12): 7.5, 6.2, 6.0 (each m, 5H, arom. H), 1.8
(s, lSH, Cp-CH3), 0.8 (x, 3H, CH3) . Mas~ spectrum 476 M+,
correcC di~integration pattern.

Polymerization

The catalysts of the formula (I) were used for PE

' CA 02240452 1998-06-19

- ss/F 313 K wo - 23 -
polymerization in a su~pen~ion polymerization in an
autoclave. Cataly#t I is bisll-methylboratabenzene)-
zirconium dichloride. Cataly-qt II i-~ methylborata-
benze~e~(pentamethyl~yclopentadienyl)zirconium
dichloride. Catalyqt II~ iq ~l-dimethylaminoborata-
~enze~e)(pentamethylcyclopen~adienyl)zirconium
dichloride.

Example ~

2.0 mg of cataly~t II (0.0052 mmol of Zr) were dissol~ed
under argon ~hile ~tirring in 1.5 ml o~ toluene in a
Schlenk tube. The ~olution was then activated by ~;n~
3.7 ml of 30~ ~trength MAO (17.69 mmol of Al; 2r:Al =
1:3402) from Witco and thi~ ~olution wa~ added to 750 ml
of ~xxsol loo/120. The catalyst solution wa~ tran6ferred
to an autoclave. In the autoclave, polymerization wa~
carried out for one hour at a tempera~ure of 70OC and a
stirrer ~peed of 750 rpm under an ethylene partial
pressure o~ 4 bar. From the yield of 145.72 g of PE,
which is formed as a fine p~wder, the catalyst activity
is calculated a~ 7006 g PE/mmol Zr/bar C2H~/h.

~mrles 9 to 13 were carried out similarly to Example a.
The changes from Example Y are ~hown in Table 1 below.

Table 1: Polymerization Examples 9 to 13

Example Cat. ~at. Cat. Al Zr:Al Pre~sure rield Cataly~t
[mg] ~mmol][mmol~ of C,H, tg] acti~rity~
[bar]
259I 1.8 0.0052 15.77 1:3033 4 12.26 586
10I 2.q 0.007023.89 1:3413 4 17.86 641~
11II 1.7 0.0044 16.72 1:3800 4 69.76 3982 "
12III 2.4 0.005821 99 1:3791 4 41.50 17B9
13III 2.8 0.006723.~9 1:3566 ~ 42.90 1~01

~Catalyst acti~ity: [g PE/mmol Zr/bar C2H4/h]

CA 02240452 1998-06-19

~ 95/F 313 K W0 - 24 -
Preparation of organoboron compound~

Example 14

1-Dimethylamino-6-(trimethylsilyl)boracyclohexa-2,4-diene

1.5 g of l-dimethylA~;nohoratabenzenelithium ~TMEDA) were
suspended in 50 ml o~ pentane and cooled to -75~C. 1.0 ml
of chlorotrimethyl~ilane wa~ added to the ~uspension, the
~ixture wa~ allowed to warm up to room temperature and
filtered, the pentane was removed under reduced pres~ure
and the product wa~ distilled at 103~C/12 mbar. The yield
of the organoboron compound wa~ 1.0 g (84~ of theory).

l~_NMR ~CDC13); 6.80, 6.~3, 6.09, 5.97 (each m, 4H,
olefin. H), 2.76, 2.64 (each ~, 6H, ~ (CH3) Z), 2.42 (d,
6.1 Hz, lH, CH), 0.1 (s, 9H, Si(CH3)3).
Mass spectrum~ 193 M', correct disintegration pattern.

Example 15

1-Chloro-6-(trimethylsilyl)boracyclohexa-2,4-diene

4.8 gofl-dimethylamino-5-(trimethyl6ilyl)boracyclohexa-
2,4-diene were dissol~ed in 10 ml of ~ethylene chloride
and cooled to -75~C. 29 ml of a 0.89 molar solution of
BCl3 in methylene chloride were added to the a~ove
sol~tion, the mixture wa~ allowed to warm up to room
temperature, the solvent wa~ removed undèr reduced
pressure and the product was distilled at 64-65~C. The
yield of the organoboron compound was 3.36 g (-73~ of
theory).
~H-NMR (CDCl3, 250 MHz): 7.5, 6.8, 6.45 (each br., 3H,
olefin. H), 6.47 (dd, ~.4 Hz, lH, olefin. H), 3.6 ~br.,
lH, CH), 0.12 (~, ~H, Si (~H3) 3) .
Mass spectrum: 1~4 M , correct disintegration pattern.

CA 02240452 1998-06-19


~ 95/F 313 K WO - 25 -
Example 16

Bis[(6-trimethylsilyl)~oracyclohexa-2,4-dien-1-yl] oxide
(ra~ and me~o ~orm)

100 ~l of diethyl ether were cooled to -75~C a~d 0.021 g
of water and 0.473 g of 1-chloro-6-(trimethylsilyl)bora-
cyclohexa-2,4-diene were added in ~ucce~io~. The mixture
waa allowed to warm up to room temperature, the ether was
~ lOved under reduced pressure and the crude product up
to 180~C/10-3 mbar wa~ condensed in a cooled receiver. The
yield of-the organo~oron compound was 0.32 g (8~ of
theory).
lH-NMR (CDCl3~: 7.35, 6.6, 6.3, 6.1 (each m, 8H, olefin.
H), 2.84, 2.78, 2.5~ (each d, 5.2 Hz, 2H, CH), 0.1, 0.9,
O.7 (each a, 18H, Si (CH3) 3) .
Mas~ ~pectrum: 314 M , correct di~integration pattern.

Representative Drawing