COMPOSE OPTIQUEMENT ACTIF

OPTICALLY ACTIVE COMPOUNDS

Abrégé anglais

ABSTRACT
Optically active pyrimidine derivatives of the general
formula
<IMG> (I)
wherein the symbol Z represents a group of
the formula -(CH2)n- or -(CH2)n-O- in which
n stands for an integer of 1 to 4 and each
of the symbols X represents a nitrogen atom
and each of the symbols Y represents -CH- or
each of the symbols Y represents a nitrogen
atom and each of the symbols X represents -CH-
and their preparation.
The compounds of formula I are valuable components in
liquid crystalline mixtures, particularly in combination with
nematic components and are thus utilizable for electro-optic
purposes.

Revendications

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for the manufacture of the optically active
pyrimidine derivatives of the general formula:
<IMG> (I)
wherein the symbol Z represents a group of the formula
-(CH2-n- or -(CH2)n-O- in which n stands for an integer of
1 to 4 and each of the symbols X represents a nitrogen atom and
each of the symbols Y represents -CH- or each of the symbols Y
represents a nitrogen atom and each of the symbols X represents
-CH-, which process comprises
(a) reacting a compound of the general formula
<IMG> (II)
wherein the symbols X, Y and Z are as defined above, with copper-
(I) cyanide, sodium cyanide or potassium cyanide, or
39

(b) for the manufacture of optically active pyrimidine
derivatives of formula I in which each of the symbols X represents
-CH- and each of the symbols Y represents a nitrogen atom, de-
hydrating a compound of the general formula
<IMG> (III)
wherein the symbol Z has the significance given above,
(c) for the manufacture of optically active
pyrimidine derivatives of formula I in which each of the symbols
X represents a nitrogen atom and each of the symbols Y represents
-CH-, dehydrating a compound of the general formula
<IMG> (IV)
wherein the symbol Z has the significance given above,
the starting materials of formulae II, III and IV being used in
optically active or racemic form and, when a racemic starting
material of formula II, III or IV is used, a resulting racemate
being separated into the optical antipodes.

2. A process according to claim 1, wherein a compound of
formula II in which each of the symbols X represents -CH- and
each of the symbols Y represents a nitrogen atom is used as the
starting material.
3. A process according to claim 1, wherein a compound of
formula II, III or IV in which the symbol Z represents a group
of the formula -(CH2)n- or -(CH2)n-O- wherein n stands for 1
is used as the starting material.
4. A process according to any one of claims 1 to 3
inclusive, wherein a compound of formula II is reacted with
copper-(I) cyanide.
5. A liquid crystalline mixture for electro-optical
purposes which contains one or more optically active pyrimidine
derivatives of formula I given in claim 1 and nematic substances.
6. A liquid crystalline mixture for electro-optical
purposes, which contains one or more of the optically active
pyrimidine derivatives of formula I given in claim 1 and one or
more compounds of the general formula
<IMG> (V)
41

wherein the symbol R6 represents a straight-chain alkyl group
containing 2 to 8 carbon atoms, a straight-chain alkoxy group
containing 4 to 7 carbon atoms, a straight-chain alkanoyloxy
group containing 2 to 8 carbon atoms or a straight-chain alkyl-
carbonate group containing 2 to 11 carbon atoms, and/or one or
more compounds of the general formula
<IMG> (VI)
42

, wherein the symbol R7 represents a straight-
-chain alkyl group containing 4 to 7 carbon
atoms or a straight-chain alkylcarbonate group
containing 2 to 11 carbon atoms,
and/or one or more compounds of the general formula
<IMG> (VII)
, wherein the symbol R8 represents a straight-
-chain alkyl group containing 4 to 8 carbon
atoms, a straight-chain alkoxy group containing
5 to 8 carbon atoms, a straight-chain alkanoyl-
oxy group containing 2 to 8 carbon atoms or a
straight-chain alkylcarbonate group containing
3 to 11 carbon atoms,
and/or one or more compounds of the general formula
<IMG> (VIII)
, wherein the symbol R9 represents a straight-
-chain alkyl group containins 4 to 8 carbon
atoms, 2 straight-chain alkoxy group containing
4 to 8 carbon atoms, a straight-chain alkanoyl-
oxy group containing 4 to 9 carbon atoms or a
straight-chain alkylcarbonate group containing
4 to 11 carbon atoms, and n stands for 1 or 2,
and/or one or more trans-cinnamic acid esters of the general
formula
43

<IMG> (IX)
, wherein the symbol R10 represents a straight-
-chain alkyl group containing 1 to 8 carbon
atoms,
and/or one or more compounds of the general formula
<IMG> (X)
, wherein one of the symbols R11 and R12
represents a cyano group and the other
represents a straight-chain alkyl group
containing 3 to 9 carbon atoms, a straight-
-chain alkoxy group containing 2 to 9 carbon
atoms or a straight-chain alkanoyloxy group
containing 2 to 9 carbon atoms,
and/or one or more compounds of the general formula
<IMG> (XI)
, wherein each of the symbols X represents a
nitrogen atom and each of the symbols Y and Z
represents -CH- or each of the symbols Y
represents a nitrogen atom and each of the
symbols X and Z represents -CH- or each of
the symbols Z represents a nitrogen atom and
44

each of the symbols X and Y represents -CH- and one of the
symbols R1 and R2 represents a cyano group and the other
represents a straight-chain alkyl group containing 1 to 7
carbon atoms, a straight-chain alkoxy group containing 1 to
7 carbon atoms or a straight-chain alkanoyloxy group containing
2 to 7 carbon atoms.
7. A liquid crystalline mixture according to claim
5 or claim 6 which contains p-[(p-n-propylbenzyliden)amino]benzo-
nitrile, p-[(p-n-butylbenzyliden)amino]benzonitrile, p-[(p-n-
hexylbenzyliden)amino]benzonitrile and 5-[4'-(+)-2"-methyl-1"-
butyloxyphenyl]-2-[4-cyanophenyl)-pyrimidine.
8. A liquid crystalline mixture according to claim
5 or claim 6 which contains p-n-butylbenzoic acid p'-cyanophenyl
ester, p-n-pentylbenzoic acid p'-cyanophenyl ester, p-n-hexyl-
benzoic acid p'-cyanophenyl ester, p-n-heptylbenzoic acid p'-
cyanophenyl ester, 5-n-pentyl-2-(4-cyanophenyl)-pyrimidine, 5-n-
heptyl-2-(4-cyanophenyl)-pyrimidine and 5-[4'-(+)-2"-methyl-1"-
butyloxyphenyl]-2-(4-cyanophenyl)-pyrimidine.
9. A liquid crystalline mixture according to claim
5 or claim 6 which contains 4-pentyl-4'-cyanobiphenyl, 4-pentyl-
oxy-4'-cyanobiphenyl and 5-[4'-(+)-2"-methyl-1"-butyloxyphenyl]-
2-(4-cyanophenyl)-pyrimidine.
10. Optically active pyrimidine derivatives of the
general formula

<IMG> (I)
wherein the symbol Z represents a group of the formula -(CH2)n-
or -(CH2)n-O- in which n stands for an integer of 1 to 4 and
each of the symbols X represents a nitrogen atom and each of
the symbols Y represents -CH- or each of the symbols Y repre-
sents a nitrogen atom and each of the symbols X represents
-CH-.
11. 5-[4'-(+)-2"-Methyl-1"-butylphenyl]-2-(4-cyano-
phenyl)-pyrimidine and its optical antipode.
12. 5-[4'-(+)-3"-Methyl-1"-pentylphenyl]-2-(4-
cyanophenyl)-pyrimidine and its optical antipode.
13. 5-[4'-(+)-4"-Methyl-1"-hexylphenyl]-2-(4-
cyanophenyl)-pyrimidine and its optical antipode.
14. 5-[4'-(+)-5"-Methyl-1"-heptylphenyl]-2-(4-
cyanophenyl)-pyrimidine and its optical antipode.
15. 5-[4'-(+)-2"-Methyl-1"-butyloxyphenyl]-2-(4-
cyanophenyl)-pyrimidine and its optical antipode.
46

16. 5-[4'-(+)-3"-Methyl-1"-pentyloxyphenyl]-2-(4-
cyanophenyl)-pyrimidine and its optical antipode.
17. 5-[4'-(+)-4"-Methyl-1"-hexyloxyphenyl]-2-(4-
cyanophenyl)-pyrimidine and its optical antipode.
18. 5-[4'-(+)-5"-Methyl-1"-heptyloxyphenyl]-2-(4-
cyanophenyl)-pyrimidine and its optical antipode.
19. 2-[4'-(+)-2"-Methyl-1"-butylphenyl]-5-(4-cyano-
phenyl)-pyrimidine and its optical antipode.
20. 2-[4'-(+)-3"-Methyl-1"-pentylphenyl]-5-(4-cyano-
phenyl)-pyrimidine and its optical antipode.
21. 2-[4'-(+)-4"-Methyl-1"-hexylphenyl]-5-(4-cyano-
phenyl)-pyrimidine and its optical antipode.
22. 2-[4'-(+)-5"-Methyl-1"-heptylphenyl]-5-(4-cyano-
phenyl)-pyrimidine and its optical antipode.
23. 2-[4'-(+)-2"-Methyl-1"-butyloxyphenyl]-5-(4-
cyanophenyl)-pyrimidine and its optical antipode.
24. 2-[4'-(+)-3"-Methyl-1"-pentyloxyphenyl]-5-(4-
cyanophenyl)-pyrimidine and its optical antipode.
25. 2-[4'-(+)-4"-Methyl-1"-hexyloxyphenyl]-5-(4-
cyanophenyl)-pyrimidine and its optical antipode.
26. 2-[4'-(+)-5"-Methyl-1"-heptyloxyphenyl]-5-(4-
cyanophenyl)-pyrimidine and its optical antipode.
47

Description

- 2 -
,
.,
RAN 6220/12
The present invention relates to optically active
compounds. More paLticularly, the invention is concerned with
optically active pyrimidine derivatives, a process for the
manufacture thereof, liquid crystalline mixtures for electro-
-optical purposes containing same and a process for the
preparation of said liquid crystalline mixtures. The invention
is also concerned with an electro-optical apparatus containing
said pyrimidine derivatives or said liquid crystalline mixtures.
The optically active pyrimidine derivatives provided by
the present invention have the following general formula
~H3 ~ / \ ~ CN (I)
wherein the symbol Z represents a group of the
formula -(CH2)n- or -(CH2)n-~ in which n
stands for an integer of 1 to 4 and each of
the symbols X represents a nitrogen atom and
each of the symbols Y represents -C~- or each
of the symbols Y represents a nitrogen atcm
and each of the syr~ols X represents -CH-.
'
It is known that the addition of cholesteric compounds to
a matrix of nematic liquid crystals with positive anisotropy of
the dielectric constants leads to a cholesteric mixture which
;r
Cot/18.1.1978
.

I ~ - 3 - ~ '7Q~Y
undersoes a cholesteric-nematic transition upon application of
an electrical field. This phase transition is reversible and
makes possible high switching speeds of the electro-optical
apparatuses operated with such mixtures. Hitherto ~nown
cholesteric compounds have the disadvantage of a usually only
very narrow mesophase range and, as a rule, a low or even
monotropic clearing point.
Surprisingly, it has now been found that ~he optically
active pyrimidine derivatives of formula I possess not only a
wide mesophase range but also a high clearing point, by means of
which these properties of corresponding mixtures can likewise be
improved drastically. Moreover, the optically active pyrimidine
derivatives of formula I possess a strong positive anisotropy of
the dielectric constants, which has a further favourable
influence on the positive anisotropy of the dielectric constants
of corresponding mixtures. Furthermore, the present optically
active pyrimidine derivatives have a high chemical stability.
The mixtures which contain the optically active pyrimidine
derivatives of formula I can also contain other pleochroitic
colouring substances.
Examples of optically active pyrimidine derivatives of
formula I are:
5-~4'-(+)-2"-Methyl-l"-butylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
r~25 5-[4'-(+)-3"-methyl-l'Y-pentylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
, ~. . . - ~

, ~ , 4 ~ t7V ~
5-[4'-(+)-4"-methyl-1'~-hexylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-S"-methyl-l"-heptylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-2"-methyl-1"-butyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-3"-methyl-1"-pentyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-t4'-(+)-4"-methyl-1"-hexyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-5"-methyl-1"-heptyloxyphenyl~-2-~4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-2"-methyl-1"-butylphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-3"-methyl-1"-pentylphenyl3-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-4"-methyl-1"-hexylphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-~4'-(+)-5"-methyl-1"-heptylphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-2"-methyl-1"-butyloxyphenyl]-5-(4-cyanophenyl)-
-pyrimidine, -
2-[4'-(+)-3"-methyl-1"-pentyloxyphenyl~-5-(4-cyanophenyl)- :~- :
-pyrimidine,
2-[4'-(+)-4"-methyl-1"-hexyloxyphenyl~-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-5"-methyl-1"-heptyloxyphenyl]-5-(4-cyanophenyl)-
-pyrimidine
and their optical antipodes. Especia71y preferred optically
.. . .
!
'~ ' ' ' ' .

-- 5 --
. ~ 7V~
active pyrimidine derivatives of this invention are those in
which each of the symbols X represents -CH- and each of the
symbols Y represents a nitrogen atom.
According to the process provided by the present invention,
the optically active pyrimidine derivatives of formula I are
manufactured by
(a) reacting a compound of the general formula
C2H5- CH - Z ~ / \ ~ Halogen (II)
, wherein the symbols X, Y and Z have the
significance given earlier,
with copper-(I) cyanide, sodium cyanide or potassium cyanide,
or
(b) for the manufacture of optically active pyrimidine
derivatives of formula I in which each of the symbols X
represents -CH- and each of the symbols Y represents a nitrogen
atom, dehydrating a compound of the general formula
~H5- CH-Z ~ \ ~ C - NH2 (III)
, wherein the sym~ol Z has the significance
given earlier,
or
(c) for the manufacture of optically active pyrimidine
derivatives of formula I in which each of the symbols X
,~ .
~. ;

- 6 ~ 7~
represents a nitrogen atom and each of the symbols Y represents
-CH-, dehydrating a compound of the general formula
C2H5-~H-Z ~ N ~ CH=N-OH (IV)
, wherein the symbol Z has the significance
given earlier,
the starting materials of formulae II, III and I~ being used in
optically active or racemic form and, when a racemic starting
material of formula II, III or IV is used, a resulting racemate
being separated into the optical antipodes.
In embodiment (a) of the foregoing process, a compound of `
formula II is reacted with copper-(I) cyanide, sodium cyanide
or potassium cyanide. This reaction is conveniently carried
out in an inert organic solvent such as ethyleneglycol,
tetrahydrofuran, dimethylformamide, dimethyl sulphoxide, -
pyridine, acetonitrile and the like. The temperature and
pressure are not critical aspects of this reaction. The
reaction is conveniently carried out at atmospheric pressure
and a temperature between room temperature and the boiling
point of the reaction mixture. The halogen atom present in
the compound of formula II is preferably a bromine atom.
The dehydration of a compound of formula III in accordance
with embodiment (b) of the foregoing process can be carried out
using any suitable dehydrating agent such as phosphorus oxy-
chloride, phosphorus pentoxide, thionyl chloride, acetic
-
.:

7(~
anhydride and the like. The dehydration can be carried out in
an inert organic solvent such as a hydrocarbon or halogenated
hydrocarbon and the like, if necessary in the presence of a
base such as sodium acetate, pyridine, triethanolamine and the
S like. The dehydration can, however, also be carried out in the
absence of an organic solvent. The dehydration is conveniently
carried out at the reflux temperature of the mixture. Althoush
the pressure is not critical, the dehydration is preferably
carried out at atmospheric pressure.
In embodiment ~c) of the foregoing process, a compound of
formula IV is dehydrated. The dehydration is conveniently
carried out using acetic anhydride or using anhydrous sodium
acetate in glacial acetic acid or also under the conditions
described hereinbefore in connection with the dehydration of a
lS compound of formula III. The dehydration is carried out at
the reflux temperature of the mixture. Although the pressure
is not critical, the dehydration is advantageously carried out
at atmospheric pressure.
The cleavage of a racemate obtained into the optical
antipodes can be carried out in a manner known per se; for
example, by salt formation with an optically active acid or,
after saponification of the cyano group, by salt formation with
an optically active base and fractional crystallisation of the
resulting salts.
The compounds of formulae II, III and IV used as the
_ starting materials are novel and also form part of the present
invention.
,

'70~
The novel compounds of formulae II, III and IV can be
prepared in a manner known per se as illustrated by Formulae
Schemes I to IV hereinafter for such compounds in which the
halogen atom is a bromine atom and the symbol A represents a
group of the formula
C2H5- CH -Z -
in which the symbol Z has the significance given earlier.

9- ~V~'~70~;
Formula Scheme I
A~3CHo
3 P - CH 2 CH 3 Cl
~NaH
A~3 / C H - OC H 3
C(C2 H5)3
BF3 O~C2H5)2
~OCH3
A~ CH N C ~Br
CH(C2 H5 )2
H~) / H 2 ¦ 1) HCI/C2 H50H :-
~2)NH3
A~ ,~CH-OC2H5 HClHN~ ~Eir
yc H 3
CH3011
A~ ~a, (IIa) ~ - :
N

- 10- ~ 0
~ormula Scheme II
B r ~3 C H0
103- P -CH20CH3CI
NaH
~CH-OCH3
HC(OC2H5~3
E3F3- O~C2H 5)2
/OCH3 .
Br~3 CH NC~3A
2 S ) 2
,H~/H20 ¦ 2 50H
~2 3NH3
Br~ 4~ 2HS HCI HN~
\/
NaOCH3
CH30H
Br ~ \~3A (IIb)
: ' . ' ~ ' ~,'- '' - - '
:. , ~ : ~ . ................. . -
: , . .,' .
: ~ j'' ~ ' . .

7~3
Formula Scheme III
A ~ C H O
3 2 3
1 NaH
A~ ~CH-OCH3 NC ~ ~
OCH3
HC10C2H5)3 . -1 ) HCIIC H OH
BF3 0(C2 H5)3 2 5
~OCH3
A~ CH(OC2H5~2 H N~ 0~2H5
H / H20 ¦ N H3/Pressure
A~ ~CHOC2H5 HCI HN~ ~C
CHO t H2N NH2
~/CH3
C H30H
A ~C N h~ C N H2 ( III )
..,
. , . .
, :
.
: . . ' ~,;, ~ ' , :

7~
- Formula Scheme IV
HOCH2~CHo
103- P -CH20CH3CI
J~NaH
~ ~CH-OCH3
HOCH2~ CH
2 5 ) 3
3F3 0(C2H5)2
/OC H3
CH
HOCH2~ C\ C2 H5
C H t~C 2 H 5 )2
H /H2
~ CHOC2H5 HCI- HN
H O C.H 2~ C H O ~ ~A
\/
¦NaOCH3
J~ C~30H
HOCH2~ \>~--A
,~
"''

70~
Formula Scheme IV (continued)
OHC ~ N ~ A
¦ NH20H- HCl
t Pyridin
HO-N=CH ~ \ ~ A ~IV)
The optically active pyrimidine derivatives of formula I
are conveniently used in the form of mixtures with nematic
substances; for example, with compounds of the general formula
S R6 ~ CH ~ ~ CN ~V)
, wherein the sy~bol R6 represents a straight-
-chain alkyl group containing 2 to 8 carbon
atoms, a straight-chain alkoxy group containing
4 to 7 carbon atoms, a straight-chain
- 10 alkanoyloxy group containins 2 to 8 carbon
.
. .
: . , ` : ,., :

7~
atoms or a straight-chain alkylcarbonate
group containing 2 to 11 carbon atoms,
and/or with compounds of the general formula
R7~=CH~CN (VI)
, wherein the symbol R7 represents a
straight-chain alkyl group containing 4 to 7
carbon atoms or a straight-chain al~yl-
carbonate group containing 2 to 11 carbon
atoms,
10 and/or with compounds of the general formula
R~ ~ C00 ~ CN (VII)
wherein the symbol R8 represents a straight-
-chain alkyl group containing 4 to 8 carbon
atoms, a straight-chain alkoxy group
containing 5 to 8 carbon atoms, a straight-
-chain alkanoyloxy group containing 2 to 8
carbon atoms or a straight-chain alkyl-
carbonate group containing 3 to 11 carbon
atoms,
20 and/or with compounds of the general formula
R9~C~ (VIII)
.. ~ ~ -
'
.
. . .

- 15 ~ 1~7V~
, wherein the symbol Rg represents a straight-
-chain alkyl group containing 4 to 8 carbon
atoms, a straight-chain alkoxy group
containing 4 to 8 carbon atoms, a straight-
-chain alkanoyloxy group containing 4 to 9
carbon atoms or a straight-chain alkyl-
carbonate group containing 4 to 11 carbon
atoms and n stands for 1 or 2,
and/or with trans-cinnamic acid esters of the general formula
10 ~ CH-CH-C00 ~ CN (IX)
, wherein the symbol Rlo represents a
straight-chain alkyl group containing 1 to 8
carbon atoms,
and~or with compounds of the general formula
R~ R~ (X)
, wherein one of the symbols Rll and R
represents a cyano group and the other
represents a straight-chain alkyl group
containing 3 to 9 carbon atoms, a straight-
-chain alkoxy group containing 2 to 9 carbon
atoms or a straight-chain alkanoyloxy group
containing 2 to 9 carbor. atoms,
and/or with compounds of .he general formula
,"r
-
: . :
'' ' :
:" . ' ~:

- 16 - i ~
Rl ~ ~ ~ / \ ~ R2 (XI)
Z X=Y
wherein each of the symbols X represents a
nitrogen atom and each of the symbols Y and Z
represents -CH- or each of the symbols Y
represents a nitrogen atom and each of the
symbols Y and Z represents -C~ or each of the
symbols Z represents a nitrogen atom and each
of the symbols X and Y represents -CH- and one
of the symbols R1 and R2 represents cyano and'
the other represents a straight-chain alkyl
group containing 1 to 7 carbon atoms, a
straight-chain alkoxy group containing 1 to 7
carbon atoms or a straight-chain alkanoyloxy
group containing 2 to 7 carbon atoms.
The optically active pyrimidine derivatives of formula I
are present in nematic mixtures for electro-optical purposes in
a weig~t ratio which preferably corresponds to the eutectic
composition. The amount of an optically active pyrimidine
derivative of formula I present in a nematic mixture is,
however, generally between about 1 and about 40 percent by
weight, preferably between S and 30 percent by weight and
especially between about 5 and 15 percent by weight.
Examples of preferred mixtures are the following, the
percentages being expressed as mol percentages:

12.7% of p-~(p-n-Propylbenzyliden)amino]benzonitrile,
34.5~ of p-[(p-n-butylbenzyliden)amino]benzonitrile, 46.9~ of
p-[(p-n-hexylbenzyliden)amino]benzonitrile and 5.4% of 5-[4'-
-(+)-2"-methyl-1"-butyloxyphenyl]-2-(4-cyanophenyl)-pyrimidine;
clearing point 72.2C;
11.2~ of p-n-butylbenzoic acid p'-cyanophenyl ester, 12.5%
of p-n-pentylbenzoic acid p'-cyanophenyl ester, 16.0% of p-n-
- -hexyl-benzoic acid p'-cyanophenyl ester, 17.2% of p-n-heptyl-
benzoic acid p'-cyanophenyl ester, 11.9~ of 5-n-pentyl-2-(4-
-cyanophenyl)-pyrimidine, 23.2~ of 5-n-heptyl-2-(4-cyanophenyl)-
-pyrimidine and 7.3% of 5-[4~-~f)-2ll-methyl-l~-butyloxyphenyl]
-2-(4-cyanophenyl)-pyrimidine; clearing point Z5.6C; and
55.7% of 4-pentyl-4'-cyanobiphenyl, 33.2% of 4-pentyloxy-
-4'-cyanobiphenyl and 6.4% of 5-~4'-(~)-2"-methyl-1"-butyloxy-
phenyl]-2-(4-cyanophenyl)-pyrimidine; clearing point 60.3C.
The compounds of formula XI hereinbefore are novel and can
be obtained, for example, by reacting à compound of the seneral
formula
R3 ~ z X X ~ y ~ (XII)
, wherein one of the symbols R3 and R4
represents a straight-chain alkyl group
containing 1 to 7 carbor. atoms, a straight-
-chain alkoxy group containing 1 to 7 carbon
.~
- .' , , . ' ' ~ , ,
.

- 18 _ ~ 7U 6
atoms or a straight-chain alkanoyloxy group
containing 2 tG 7 carbon atoms and the other
represents a halogen atom and the symbols X,
Y and Z have the significance given earlier,
with copper-(I) cyanide, sodium cyanide or potassium cyanide.
This reaction can be carried out in an analogous manner to
that descri~ed earlier in connection with the reaction of a
compound of formula II with copper-(I) cyanide, sodium cyanide
or potassium cyanide.
lOThe preparation of the compounds of formula XII can be
effected according to the disclosure in the unexamined German
Patent Publication (DOS) No 2641724 and is illustrated in the --
following Formulae Schemes A to F for such compounds in which
one of the symbols R3 and R4 represents a straight-chain alkyl
group containing 1 to 7 carbon atoms and the other represents
a bromine atom.
.
,~
.
. : ~ , , .
- . : . . .

- 1 9 ~ 7
F~rmula Scheme A
A I k y I ~ CH O
~3-P -CH20CH3CI
~NaH
~ /fH-OCH3
AI kyl ~ ~CH
HC(OC2H5)~ ,
BF3 O(C2H5)2
1 ~ ~OCH3 ~ .
AlkY1~3cH OC2H5 NC~Br
2 5 2
I H/H20 ¦ t)HCI/C21~50H
~2)N H3
,~ ~CH -OC2H5 HCI HN~
A l k y l--~,=J~ C\ C H OH 2 N
\/
¦ N aOC H3
J~CH301~
A I ~yl ~ \~3Br (XIIa)
N
.
. . . ~ -
--,..

- 20- 1~7()6
Formula Scheme B
~r ~CH0
103- P -CH20C H3Cl
~NaH
3 r ~3 C H - OCH3
( 2 533
BF3-0(C2H5J2
~ ~ /OC H3
8 r ~3 C H N C ~AIkyl
2 5 ) 2
H~'IH 2 1 1 )HCIJC2H50H
~2 )NH~ :
,~ CHOC2H5 HCI HN ~
3 r ~=~C + ~C ~ Alkyl
CHO H2N \=./
\/
. NaOCH j
C H 30 H
ar ~ \)~,3Alkyl (XIIb)
'

- 2~ 706
Formula Scheme C
A l k y l ~CHO
¦ G~3 P -CH20CH3CI
~ NaH
All~yl ~ ~CH-OCH3
2 5 ) 3
3F3- O(C2 H5)2
~OCH3
Alkyl ~-CH OC2H
CH(OC2H5~2
¦ H IH20
.
A I k y l ~ ~ H - O C 2 H 5 H 2 N ~ '
Y
A l ky l ~ ~--OH
¦ POar3
(~IIc~ A I k y I ~ ~NN~--B~
. .

~Z7(~6
-- 22 --
Schema D
~r ~3
¦ TiC14
C H 30C HCl~
Br ~CHO
~ NH20H
2J Ac20
B r ~3CN
1 ) H Cl / C2H5 0 H
2) NH3
,~ ~NH HCl C2H50HC~
e,~c C-Alkyl
NH2 ~ OHC
/
yNaOCH3
~ CH30H
X I 1 d B r ~(/ 3--Alky l
- ~ ~
- - .
; ~ ' ' ,
. : ~, '' , , -

7V6
-- 23 --
Schema E
Al kyl ~C N
1 ) HCI/C2H50H
2) NH3
A l k y l ~ ~ C H3 0 H C~
\~C H3
CH30H
Xll e Alkyl ~ 3Br
. . . . . .... .
~ : , . . : .,

7()~
-- 24 --
Schema F
B r ~3
TjCIL
l C H30C H C12
Br~3CHo
¦ 0 3 - PG>-CH 20C H 3Cl0
J, NaH
Br ~ ~CH-OCH3
¦ C~O 2 5)3
3 2 5~2 OCH
B r ~3 CH NC -Alkyl
CH~C2HS~2 ¦11HCIIC2H50H
e r ~3 + ~ -Alkyl
YN aOC H3
C H30H
~ r ~ Alkyl
~ ! '
'

- 25 ~ 7V~
The term "straight-chain alkyl group containing 1 to 7
carbon atoms" used in this specification means methyl, ethyl,
n-propyl, n-butyl, n-pentyl, n-hexyl and n-heptyl. The term
"straight-chain alkoxy group containing 1 to 7 carbon atoms"
means methoxy, ethoxy, n-propoxy, n-butoxy, n-pentyloxy,
n-hexyloxy and n-heptyloxy. The term "straight-chain
alkanoyloxy group containing 2 to 7 carbon atoms" means acetoxy,
n-propionyloxy, n-butyryloxy, n-valeryloxy, n-hexanoyloxy and
n-heptanoyloxy.
~ . . ,~ . . . . ............................ . . .
:` '' ,," '"" ' ' ' . ' '~ .. ' : '.
,

- 26 -
. The following Examples illustrate the process provided by
the present invention:
Example 1
1.9 g of 2-~4'-~+)-2"-methyl-1"-butylphenyl]-5-(4-bromo-
phenyl)-pyrimidine are heated at reflux for 21 hours in S0 ml
of dimethylformamide with 2.5 g of copper-(I) cyanide (content
70~). After cooling, the mixture is stirred up with 25 ml of
10~ aqueous ethylenediamine solution and subsequently extracted
with methylene chloride. The extract is again washed with
aqueous ethylenediamine solution and then several times with
water until neutral. The crude product obtained after
evaporation is chromatographed on 150 g of silica gel with
toluene/1% acetone. There are obtained firstly traces of
starting material and then fractions containing pure 2-[4'-(+)-
-2"-methyl-1"-butylphenyl]-5-(4-cyanophenyl)-pyrimidine.
The starting material can be prepared as follows:
A solution of 15 g of 1-(4-bromophenyl)-2-methoxyethylene
in 150 ml of ethyl orthoformate is added dropwise at 0-5C to
5 g of boron trifluoride etherate in 200 ml of ethyl ortho-
formate. The mixture is stirred overnight, the mixturereaching room temperature. The mixture is diluted with ether
and washed with soda solution and then with water until neutral.
The crude product obtained after evaporation yields, a'ter
recrystallisation from hexane, 4-bromophenol-malonic tetra-
acetal. ~082706 ~ `
.~.
.
. .
- ~
.. . . . ~ .
.

~0~'~7(~
. In order to partially hydrolyse the foregoing tetraacetal,
4.5 g thereof are dissolved in 10 ml of ethanol, treated with
0.5 ml of water and 1 drop of concentrated sulphuric acid,
stirred overnight at 50C and then wor~ed-up in the usual manner.
There is thus obtained crude 2-(4-brGmophenyl)-3-ethoxyacrolein
which is used in the next step in crude form.
To a sodium methylate solution prepared from 0.7 g of
sodium in 25 ml of methanol are added firstly 2.5 g of crude
2-(4-bromophenyl~-3-ethoxyacrolein in 20 ml of methanol and then
2.4 g of 4-(+)-2'-methyl-1'-butylbenzamidine hydrochloride.
The mixture is heated at reflux overnight Subsequently, the
solvent is distilled off partially, the residue is treated with
water and acidified with dilute hydrochloric acid. ~he
precipitate is filtered off, washed thoroughly with water and
ether and dried. The crude 2-[4"-(+)-2"-methyl-1"-butyl-
phenyl]-5-(4-bromophenyl)-pyrimidine is used in the process
without further purification.
The following compounds can be manufactured in an
analogous manner:
5-[4'-(+)-2"-~ethyl-1"-butylphenyl]-2-(4-cyar.ophenyl)-
-pyrimidine,
5-[4'-(+)-3"-methyl-1"-pentylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-4"-methyl-1"-hexylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-5"-methyl-1"-heptylpnenyl]-2-(4-cyanophenyl)-
-pyrimidine,
,.. ,, . ~ , . ~ . , ... , :
~ ' ' ' .
: ' ' , ' :
.

- 2~ -
7Vf~i
5-[4'-(+)-2"-methyl-1"-butyloxvphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-~4'-(+)-3"-methyl-1"-pentyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-4"-methyl-1"-hexyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine of melting point 121-122C and clearing point
238.5C,
5-[4'-(+)-5"-methyl-1"-heptyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-3"-methyl-1"-pentylphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-4"-methyl-1"-hexylphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-5"-methyl-1"-heptylphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-2"-methyl-1"-~utyloxyphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-~4'-(+)-3"-methyl-1"-pentyloxyphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-4"-methyl-1"-hexyloxyphenyl]-5-(4-cyanophenyl)-
-pyrimidine, and
2-[4'-(+)-5"-methyl-1"-heptyloxyphenyl]-5-(4-cyanophenyl)-
-pyrimidine.
Ex~mple 2
4.2 g of 4-/ 5-[4'-(+)-2"-methyl-1"-butyloxyphenyl]-2-
-pyrimidyl /-benzoic acid amide are left at reflux for 1 hour
while stirring in a mixture of 200 ml of ethylene chloride and
., '
'.
'

- 29 -
~ (3~
2.5 ml of phosphorus oxychloride. The mixture, diluted with
ether, is washed with 2-~ sodium hydroxide and then neutral
with water. The organic phase is dried over sodium sulphate
and evaporated to give 5-[4'-(+)-2"-methyl-l"-butyloxyphenyl]-
S -2-(4-cyanophenyl)-pyrimidine which is filtered through a short
silica gel column and subsequently recrystallised from methylene
chloride/methanol; melting point 149.9C; clearing point
233.8C.
The starting material can be prepared as follows:
Dry hydrochloric acid gas is passed while stirring at 0C
for 3 hours into a soIution of 88.6 g of methyl 4-cyanobenzoate
in l90 ml of benzene and 70 ml of methanol. The mixture is
left to stand at 5C for 5 days and the separated imidoether is
then filtered off. 178 g of this crude imidoether are
suspended in 300 ml of methanol and the suspension is cooled to
ca -40C, treated with 130 g of liquid ammonia and shaken at
70C for 24 hours in an autoclave. After cooling the mixture
to room temperature and discharging the ammonia, the crystallised-
-out product is filtered off under suction, the crystals are
washed with hexane and drièd overnight at 50C in a water-jet
vacuum, there being obtained 4-amidinobenzoic acid amide
hydrochloride.
46.07 g of 1-[4'-(+)-2"-methyl-1"-butyloxyphenyl]-2-
-methoxyethylene are added dropwise to a solution, cooled in an
ice-bath, of 2 ml of boron trifluoride etherate in 500 ml of
ethyl orthoformate and the mixture is subsequently stirred at
,~

- - 30 ~ 7~
room temperature. After dilution with ether, extraction with
l-N sodium hydroxide and water, drying over sodium sulphate and
evaporation of the organic phase, there is obtained 4-(+)-2'-
-methyl~ butyloxyphenyl-malonic tetraacetal.
7.33 g of 4-(+)-2'-methyl-1'-butyloxyphenyl-malonic
tetraacetal are stirred overnight at 50C under nitrogen in
20 ml of ethanol with 0.72 ml of water and 2 drops of
concentrated sulphuric acid. The mixture is diluted with
ether and shaken out with aqueous sodium carbonate solution to
separate the acidic (+)-2-methyl-butyloxyphenyl-malonaldehyde,
which results as a byproduct, from neutral 2-[4-(+)-2'-methyl-
-l'-butyloxyphenyl]-3-ethoxyacrolein.
4.46 g of 2-[4-(+)-2'-methyl-1'-butyloxyphenyl]-3-ethoxy-
acrolein, 3.63 g of the aforementioned 4-amidinobenzoic acid
amide hydrochloride and 0.0254 mol of sodium methylate (obtained
by dissolving 0.584 g of sodium metal in methanol) are suspended
in 250 ml of methanol and stirred overnight at room temperature
under nitrogen. The yellow suspension is subsequently filtered
under suction, washed with a small amount of ethanol and, for
further purification, suspended in 1.4 litres of ether. The
suspension is washed with water and again filtered. There is
obtained difficultly soluble 4-rs- [4'-(+)-2"-methyl-1"-
-butyloxyphenyl]-2-pyrimidinyl_/-benzoic acid amide.
The following optically active pyrimidine derivati~-es can
be manufactured in an analogous manner:
::. . . .
~.

~ . - 31 - ~ 7~
5-[4'-(+)-2"-Methyl-l"-butylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-3"-methyl-1"-pentylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
;5-[4'-(+)-4"-methyl-1"-hexylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-5"-methyl~ heptylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-3"-methyl-1"-pentyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(~)-4"-methyl-1"-hexyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine of melting point 121-122C and clearing point
238.SC, and
5-[4'-(+~-5"-methyl-1"-heptyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine.
` .
Example 3
2.0 g of 5-~4'-(+)-2"-methyl-1"-butyloxyphenyl3-2-(4-
-bromophenyl)-pyrimidine are heated at reflux fGr 30 hours with
3.15 g of copper-(I) cyanide in 100 ml of dimethylIormamide.
The mixture is cooled, 50 ml of 10% aqueous ethylenediamine
solution are added thereto and the resulting mixture is stirred
for a short period and then extracted with methylene chloride.
The organic extract is again shaken with 30 ml of ethylene-
diamine solution and then washed with water until neutral. The
crude concentrate is chromatographed on silica gel with toluene/
1~ acetone. Recrystallisation of the pure fractions from
methanol/methylene chloride gives 5-[4'~ 2"-methyl-1"-butyl-
. . .
. : ~
.''

- 32 -
"~ V~
oxyphenyl)-2-~4-cyanophenyl~-pyrimidine of melting point 149.5C
and clearing point 233.5C.
The starting material can be prepared as follows:
2.4 g of p-bromobenzamidine hydrochloride, obtained from
p-bromobenzonitrile in the usual manner, are added to a solution
of 0.7 g of sodium in 20 ml of methanol and then treated (as
described in Example 2) with 2.5 g of crude 2-[4-t2-methyl-
butyloxy)phenyl]-3-ethoxyacrolein. The mixture is heated
overnight at reflux, the solvent is su~sequently distilled off
partially and the residue is treated with ether. After
acidification with dilute hydrochloric acid, the precipitate
obtained is filtered off, washed thoroughly with water and ether
and finally dried. The crude 5-~4'-(~)-2"-methyl-1"-butyloxy- -
phenyl]-2-(4-bromophenyl)-pyrimidine is used in the process
without further purification.
The following optically active pyrimidine derivati~es can
be manufactured in an analogous manner:
5-[4'-(+)-2"-Methyl~ utylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-3"-methyl-1"-pentylphenyl]-2~(4-cyanophenyl)-
-pyrimidine,
5-[4'-(+)-4"-methyl-1"-hexylphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5-~4'-(+)-5l'-methyl-1"-heptylphenyll-2-(4-cyanophenyl)-
-pyrimidine,
"
'

. . ~ 33 ~ 1~ 7~
5-[4'-(+)-3"-methyl-1"-pentyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
5 t4'-(+)-4"-methyl-1"-hexyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine of melting point 121-122C and clearing point
238.5C,
5-[4'-(+)-5"-methyl-1"-heptyloxyphenyl]-2-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-2"-methyl-1"-butylphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-~4'-(+)-3"-methyl-1"-pentylphenyl3-5-(4-cyanophenyl)- -
-pyrimidine, . .
2-[4'-(+)-4"-methyl-1"-hexylphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-5"-methyl-1"-heptylphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-2"-methyl-1"-butyloxyphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-[4'-(+)-3"-methyl-1"-pentyloxyphenyl]-5-(4-cyanophenyl)-
-pyrimidine,
2-~4'-(+)-4"-methyl-1"-hexyloxyphenyl]-5-(4-cyanophenyl)-
-pyrimidine, and
2-[4'-(+)-5"-methyl-1"-heptyloxyphenyl]-5-(4-cyanophenyl)-
-pyrimidine.
The following Examples illustrate the preparation of the
compounds of formula XI hereinbefore:
Exam~le A
,r
1.9 g of 2-(4-n-hexylphenyl)-5-(4-bromophenyl)-pyrimidine
''''"'`''~ : ~
": ~' ' ' ' ' .
,
,~ ' .

_ 34 _ 7~6
are heated at reflux for 21 hours in 50 ml of dimethylformamide
with 2.5 g of copper-(I) cyanide (content 70~ fter cooling,
the mixture is stirred with 25 ml of 10% aqueous ethylenediamine
solution and subsequently extracted with methylene chloride.
The extract is again washed with aqueous ethylenedïamine
solution and then several times with water until neutral. The
crude product obtained after evaporation is chromatographed on
150 g of silica gel with toluene/1~ acetone. There are
obtained firstly traces of starting material and then fractions
containing pure 2-(4-n-hexylphenyl)-5-(4-cyanophenyl)-pyrimidine.
After recrystallisation from acetic ester, the product has a
melting point of 121.5C and a clearing point of 250C.
The starting material can be obtained as follows:
A solution of 15 g of 1-(4-bromophenyl)-2-methoxyethylene
in 150 ml of ethyl orthoformate is added dropwise at 0-5C to
5 g of boron trifluoride etherate in 200 ml of ethyl orthoformate.
The mixture is stirred overnight and reaches room temperature.
The mixture is then diluted with ether and washed firstly with
soda solution and then with water until neutral. The crude
product obtained after evaporation yields 4-bromophenyl-malonic
tetraacetal after recrystallisation from hexane.
In order to partially hydrolyse the foregoing acetal,
4.5 g thereof are dissolved in 10 ml of ethanol, the solution is
treated with 0.5 ml of water and 1 drop of concentrated sulphuric
acid and the mixture is stirred at 50C overnight and then
worked-up in the usual manner. There is thus obtained crude 2-
-(4-bromophenyl)-3-ethoxyacrolein which is used in the crude form.
.. .. . .
.
- ,
. .

- 35 ~ 7'0~
To a sodium methylate solution prepared from 0.7 g of
sodium in 25 ml of methanol are added firstly 2.5 g of crude
2-(4-bromophenyl)-3-ethoxyacrolein in 20 ml of methanol and then
2.4 g of 4-n-hexylbenzamidine hydrochloride. The mixture is
heated to reflux overnight. Subsequently, the solvent is
distilled off partially, the residue is treated with water and
acidified with dilute hydrochloric acid. The resulting
precipitate is filtered off, washed thoroughly with water and
ether and dried. The crude 2-(4-n-hexylphenyl)-5-(4-bromo-
phenyl)-pyrimidine of melting point 152.5-156C is used in the
process without further purification.
The following compounds were prepared in an analogous
manner:
Melting point Clearing point
15 2-(4-Ethylphenyl)-5-(4-cyano-
phenyl)-pyrimidine 167-167.5C 279-279.5C
2-(4-n-Propylphenyl)-5-(4-
-cyanophenyl)-pyrimidine167C 278.5-279C
2-(4-n-Butylphenyl)-5-(4-cya~o-
phenyl)-pyrimidine 138.5C 266-266.5;C
2-(4-n-Pentylphenyl)-5-(4-
-cyanophenyl)-pyrimidine131.5C 262.5-263C
2-(4-n-Heptylphenyl)-5-(4-
-cyanophenyl)-pyrimidine121.5C 245-245.5C
Example B
1.5 g of 5-n-pentyl-2-(4'-bromo-4-biphenylyl)-pyrimidine
are heated at reflux for 22 hours with 2.5 g of copper-(I)
r cyanide (content 70%) in 50 ml of dimethylformamide. After
~: , '
,

- 36 - i~ 7~
- cooling, 25 ml of 10% aqueous ethylenediamine solution are added
and, after stirring for a short time, the mixture is extracted
with methylene chloride. The organic extract is shaken with a
further 25 ml of ethylenediamine solution and then washed until
neutral. The crude concentrate is chromatographed on silica
gel with toluene/1% acetone. Recrystallisation of the pure
fractions from ethyl acetate yields 5-n-pentyl-2-(4'-cyano-4-
-biphenylyl)-pyrimidine of melttng point 123.5-124C and
clearing point 204.5-205C.
The starting material can be obtained as follows:
34.5 g of 4-bromobiphenyl in 164 ml of methylene chloride
are treated at ca 2C with 60.6 g of titanium tetrachloride.
At the same temperature there are added dropwise over a period
of 40 minutes 20.7 g of dichloromethyl methyl ether'. The
cooling means is removed and the mixture is l'eft to stir at
room temperature for 21 hours. The mixture is poured on to
ice and the product is extracted with ether in the usual manne..
Chromatography on silica gel using benzene for the elution gives
firstly unreacted starting material and then 4'-bromo-4-
-biphenylaldehyde.
From 17.5 g of 4'-bromo-4-biphenylaldehyde and 4.4 g of
hydroxylamine hydrochloride in 35 ml of methanol and 70 ml of
pyridine there is obtained, after boiling under reflux, crude
oxime, which is converted into the nitrile by heating for 15
hours in acetic anhydride. The mixture is concentrated as
much as possible on a rotary evaporator. The residue is
,, . , : .,

. ~ 37 ~ 1~27~ .
poured on to ice and dilute sodium hydroxide and the product is
isolated with ether in the usuaL manner. After treatment with
hexane, the 4'-brGmo-4-cyanobiphenyl melts at ca 150C.
Gaseous hydrochloric acid is passed into a mixture of
5.6 g of 4'-bromo-4-cyanobiphenyl and l g of absolute ethanol in
25 ml of toluene until the mixture becomes saturated. After
stirring for 3 days at room temperature, the precipitate is
filtered off and washed with toluene. The residue is suspended
while still moist in 5 ml of absolute ethanol and the suspension
is treated with ca 1.3 g of ammonia in the form of a lO~
ethanolic solution. After stirring for 3 days at room
temperature, the precipitated 4'-bromo-4-biphenylamidine hydro-
chloride is separated, washed with ether and dried.
5.8 g of n-pentyl-malonic tetraacetal are stirred at room
temperature overnight in lO ml of ethanol with 0.75 ml of water
and 1 drop of concentrated sulphuric acid. The mixture is then
diluted with ether, extracted with sodium carbonate solution,
washed neutral and evaporated.
1.42 g of the thus-obtained crude 2-n-pentyl-3-ethoxy-
acrolein are dissolved in a sodium ethylate solution (obtainedfrom 580 mg of sodium in 40 ml of ethanol) and treated with
2.6 g of the aforementioned 4'-bromo-4-biphenylamidine hydro-
chloride. The mixture is stirred at room temperature for 3
da~s. After some of the solvent has been distilled off, water
is added and the mixture is extracted with chloroform in the
usual manner. Upon crystallisation from ethanol, there is
.
.
.

_ 33 - ~ 7~
.
obtained 5-n-pentyl-2-(4'-bromo-4-biphenylyl)-pyrimidine in the
form of needles of melting point 137C and clearing point 197C~
The following compounds were obtained in an analogous
manner:
5-n-2ropyl-2-(4'-cyano-4-biphenylyl)-pyrimidine; melting -
point 125.6C; clearing point 275.7C;
5-n-butyl-2-(4'-cyano-4-biphenylyl)-pyrimidine; melting
point 112C; clearing point 262C;
5-n-hexyl-2-(4'-cyano-4-biphenylyl)-pyrimidine; melting
point 108C; clearing point 245C; and
5-n-heptyl-2-(4'-cyano-4-biphenylyl)-pyrimidine; melting
point 110C; clearing point 241.5C.
.