Note: Descriptions are shown in the official language in which they were submitted.
The present invention relates to a novel group of phosphobetaines
of the formula I
Rl R3 R4
R ~?p _ C - C - CO ~ I
12 1
R H H
in which Rl is methyl and R2 has the meaning of Rl 01` of R, R being a radical
of the formula II
R3 R4
- CoOR5 II
H H
in which R3 is hydrogen and R4 is methyl or hydrogen, and R5 is alkyl of
1-4 carbons.
The invention also relates to a process for making the above
phosphobetaines.
Phosphobetaines which contain ester groups in addition to the
carboxylate group in the molecule have
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not been. described hereto~ore,
The phospho'betaines described hereto~ora, in which
the quaternary phosphon:ium ion is :ln-tramolecularly
saturated `by means o~ a carboxylate ~roup~ are high-
melting stable compounds~ As described in Houben-Weyl~
Methoden der Organischen Chemie~ vol O XII~1~ page 107
et seq (Georg Thieme V~rlag, Stuttgart~ 196~)~ these
phosphobetaines are ~ormed 'by multlple stage reaction~
Trimethylphosphine~ ~or example, can be reacted wîth
chloroacetic acid to gi-ve carbox,ymethyl~trimethyl
phosphonium chloride which. can be converted to the
corresponding phosphobetaine by treatment with moist
silver oxide.
)~p+GlcH2cooH--~/ (C~ )3PCH2COOH 7 Cl~
~CH3)3P ~ CH2COO
Phosphonium salts from tert.iary phosphines and
chloroacetic acid alkyl esters~ which are admixed with
basic media, give the corresponding phosphine alkylenes
~ather than phosphobetaines containing a carbox~late
group.
A further process wherein trishydrox~methylphosphine
is additively combined with an aiB unsaturated car~oxylic
acid in accordance with the ~ollowing reaction equation:
(HOCH2)3P -~ CH2 _ CH~COOH ~ (HOCH~P~CH2CH2COOe
has been described in German Patent Speci~ication
1yO45,401~
Triphenylpho~phine has been shown to form an
analogous compound ~c~. W. Ho~mann, Chem. Ber,~ 94
~ 3 ~
1331-6 (1961)).
It has also 'been described that phosphobetaines o~
the following ~ormula
R~P~CH2 CH-C00~ "
are obtained 'by reacting a tertiary phosph.ine with an . '
a,B~unsaturated carboxylic acid ester. T.hese, however~
are unstable phosphobetaines which undergo ~ur-ther
reaction.with the resultant ~ormatiorl of polymers or
phosphine alkylenes (M.~. Shaw and R. S~ Ward7 Topics
in Phosphorus Chemistry, vol. 75 1~35 (197~))0 In
e~fecting the same reacti.on L~ Horner~ W~ Jur~eleit and~
Ko KlUfpel (c~. Lie'bigs AmO Chem. 591, 108~117 (1~55~)
obtained the corresponding polymeric products o~ a,B-
unsaturated carboxylic acid esters. In other words~ the
tertiary phosphines were found to act as polyrnerlzation
.,~ . .
catalysts. The additive combination o:~ the compou~.ds
with the resultant ~o:rma-tion o~ a phosphobetaine
containing a carboxylate group has not 'been described
heretoforeO
The processes described hereinabove ~or making
phosphobetaines containing a car~oxylate ~roup are
highly unsatisfactory inasmuch as they'call for the
exclusive use of tertiary phosph.l.ne startlng materîals7
~or which it is partially necessary to be first
converted to phosphonium ~alts and :Eor the pho.sphonium
salts to be then subjected to alkaline -treatment so as
to o~tain the desired product.
In addition to this, the prior art methods can
only 'be used for making phospho~etaines into which the
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-- 4 ~
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carboxylate is introduced via a oa~;boxy~lic acid~ ~7B-
unsaturated carboxyli.c aci.d alky1. esters hav0 'bee~ ~ound
to react with tertia~y phosphines to glve phosphine
alkylenes or po'lymersO Phosphobetaines containin~ a
carboxylat~ group are not obtainable .in this marmerO
The present in~ention now ~expecte~ly prov.ides a
process for making a novel group of phosphobetaines o~
general formula I ~hich comprises reacting one or more
phosphines o~ general ~ormula III
~ ~5
\ P - H IXI
~/ ,
in which R3 has the meaning given above~ and R6
has the same meaning as R4 with the exception of :
hydrogen, with one or more a,~ unsaturated c~arbox~lic
...
acid esters of general formula I~
R3
\ C = C ~ CoOR5 IV
H '~
in which R3~ R4 and R5 equally have the meanings given ~'
hereinabove, the reaction 'being e~'~ected in a single
stage in the presence o~ water or a solvent/wa-ter-
mixture; and separating the resultin~ phosphobetaines
from the reaction product obtained.
The novel phosphobetaines of the present invention
are obtained in the ~orm of colorless, thermally
stable and highly ~iscous liquids.
A highly unexpected result resides in the fact
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that the present reac-t.ion o~ t,he .~ormula IV ~B~
unsaturated carboxylic acid esters entails subs-tantially
no s.ide reactions, e~g. poLymerization or forma-tion o~
phosphine alkylenes and seconda,~y produc,t,s~
~ f'urther hi~hly unexpected. result resides in the
:Eact that the reaction is easy to effect in a single
reaction stage without any need to separate a tertiary
~hosphine intermedlate or hydrolyze a carboxylic acid
ester group to the carboxylate group, and with the
resultant ~o~mation of high yields of desirable
phosphobetainesO me reaction should p~e:Eera~ly be
e~fected in the presen,ce of a catalyst~
The useful catalysts primarily comprise chlorides 9
~ulfates and acetates of metals, such as ca~mium~
nickel and cobalt~ The catalys-t should conveniently be
used at a rate o~ 0,1 to 10 millimol? preferably 1 to
.
5 millimo1~ based on the total mixture. It îs also
preferable -to effect the reactlon at temperatures of
O to 120C, more pre~erably 15 to 80CI
Apart from water, the reaction mixture may contain
one or more ~'urther solvents which primarily include.
alcohols or acetonitrile, It is ~inally advantageous
to effect the reaction under inert ga~$ e~g. nitrogen~
The phosphobetaines obtained by the process o~
this invention are ~ery pure (9~99 ~). They are
obtained in good yieLds a~ter disti-L:Lative removal of
the water or water/solvent-mixture~
The quantitative ratio of the reaction eomponents
is variable within wide lim.its and does not materially
influence the course o~ the reaction, It i.s good
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practice, however, to use the ~ormula III and ~ormula
:LV reac-tan-ts in the stoi.chiometric proportions necessary
for the formation of the :~or~lula X phosphobe-ta.irles.
In accordance with an advantageous ~eatur~ of the
present process the ~ormula IV a~B-unsaturated carboxylic
acid ester is introduced together with the catalyst into
an aqueous phase9 which may be water or a water/solvent-
mixture, the fo~mula III phosphine is added there~o, the
whole is reacted at 0 to 120C, the resulting reaction
solution ~is allowed to stand ~or a period of 2 to 3
hours, and the phosphobetaine is separated ~rom.the
sol~ent.
The process of the present .inverltion compare.s ve~
favorably with the~rior art methods, principally in
respect o~ the following points: It is a single stage
reaction,~which is easy to ca.rry out without any ~eed
to isolate intermediates~ and it produces readily
separable, uni~orm and very pure final products in
good yields.
The only by-product obtained .s -the alcohol
~corresponding to t~e for~ula IV corQ~ound) which can
be separated together wi.th the solven-t~
The products o~ -the present invention a~e~or .
example, suitable ~or use ln imp~rtln~ antistatic
properties to textile materia:ls.
EXAMPLE 1:
,
CH2cH2cooc~I3
C~I - P/CH2CH2CO~ .
C~2cH2coocH~ .
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.... . ._~
An agit~.tor provided apparatus scavenged w.ith
nitrogen was charged with 87 g ~1 mol) of methyl
acrylate in. 200 ml o~ water ~nd wlth 1 g o~ CdCl2 ~
2 1/2 H20O 20 g ~0.4 mol~ of methyJ.pho,sphine was added.
together with nitrogen as an .ine-~t gas within 1 h.our.
The temperature was kept within the range of 24 to
30C by cooling from the outside~ ~n intermediate
precipitate became completely dissolved during the
post reaction period of 3 hours~ The sol~ent was
distillatively separated and a c~lorles,s highly viscous
liquid remained behind.
The yield was 90 % of the theoretical~
Analysis: Found: Calculated:
P ~.9 % 10~6 %
EXAMPLE 2-
'' ';''''''- .
/ H2CH2COOC4
CH3 - P - CH2CH2C00~
CH2CH2COOC~Hg
Butyl acrylate was reacted with methylphosphine
in the manner described in Example 10 The yield was
97 ~o.
Analysis: Found: Calculated:
P 8.0 % 8.23 %
E~
0/ CH2CH2COOC~I3
3 ) 2P
\ CH2CH~,COO~
103 g (~.2 mol) o~ meth~:l acxylate in 200 ml of
~ '
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water was reacted as described irl Example 1 with 3~5
g (0.62 mol) o~` dime-thylphosphine i~ -the presence of
005 g o~ CdCl2 o 2 1~2 H20. The ~olv0nt and low~boîling
fractions were disti.~ed o~.t~ and a h:ighly v.iscous oi.l
was obtained.
The yield ~as 96 ~ of the theorekical~
Analysis: Found: Calculateds
P 13 o 5 % 1/-1706 %
~,
~CH2CH(CH3~COOCH3
CH3 ~ P ~ CH2CH(CH3)C0~9
SH~cH(cH3~cooH3
100 g ~1 mol~ of methyl methacrylate was reacted
with 20 g (004 mol) of methylphosphine, in the manner
described ln Example 1.
~he yield was 86 %.
~nalysis- Found: Calculatedo
- P808 % 9~26 %
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