Process using a cyclic carbonate reactant
The present invention relates to a process wherein a cyclic carbonate compound is reacted with a compound containing a nucleophilic group, especially an amine group, in the presence of a catalyst comprising a lithium compound. Such reactions permit to obtain urethane groups useful in polymer preparation, such as polyurethanes, or other urethane-containing polymers.
1 . Process of forming an organic compound, wherein
(a) a component (A) containing at least one cyclic carbonate group having the general formula (I):
wherein:
R 2 represents a bivalent alkylene radical: —(CR 3 R 4 ) p — with p≧2,
each R 3 and each R 4 is, independently, chosen from: hydrogen, aromatic radical, alkyl or alkenyl which contains from 0 to 8 ether bridges, and R 3 and/or R 4 may be substituted by one or more alkyl, alkenyl, aromatic radical, hydroxyl group(s), and/or cyclic carbonate group of formula (I),
(b) is reacted with a component (b) containing at least one reactive nucleophilic function X wherein each X is, independently, chosen from a primary amino or hydrazo, secondary amino or hydrazo, thiol and/or oxime,
(c) in presence of a catalyst comprising a lithium compound
(d) to form an organic compound (c) containing at least one unit of the general formula (II): —X—CO—O—.
2 . Process according to claim 1 , wherein component (A) contains at least one 5-membered cyclic carbonate group (p=2 in general formula (I)).
3 . Process according to claim 1 , wherein component (A) contains at least two carbonate cycles.
4 . Process according to claim 1 , wherein component (A) is chosen from propylene carbonate, ethylene carbonate, butylenecarbonate, glycerinecarbonate, allyloxymethylcarbonate and biscarbonates made starting from the diglycidylethers of bisphenol A or of polypropylene glycol.
5 . Process according to claim 1 , wherein component (B) contains at least one nucleophilic function X which is an amino group.
6 . Process according to claim 5 , wherein component (B) is an amine of formula (IX), (X), (XI) or (XII)
wherein
R 33 is an alkyl, optionally substituted by hydroxy, tertiary amine and/or aryl, and optionally containing from 1 to 20 ether bridges and/or from 1 to 3 tertiary amine bridges,
R 34 , R 5 , R 6 , R 12 , R 13 , R 14 , R 15 and R 16 are, independently, chosen from the group of
hydrogen, and
alkyl, optionally substituted by hydroxy, tertiary amine and/or aryl, and optionally containing from 1 to 8 ether bridges and/or from 1 to 3 tertiary amine bridges,
with the proviso that, respectively, R 33 and R 34 , R 5 and R 6 , R 12 and/or R 13 and/or R 14 , R 15 and R 16 may be linked together in order to form a ring,
R 7 , R 8 , R 9 , R 10 , R 17 and R 18 are, independently, chosen from alkylene, alkenylene, arylene and aralkylene chains which may contain from 1 to 8 ether bridges and/or from 1 to 3 tertiary amine bridges,
R 11 is hydrogen or alkyl.
7 . Process according to claim 5 , wherein component (B) contains at least two primary or secondary amino groups.
8 . Process according to claim 6 , wherein component (B) is an amine chosen amongst cyclohexylamine, N-methylbutylamine, N-methylbenzylamine, piperidine, piperazine, morpholine, benzylamine, diethylenetriamine, ethanolamine, diethanolamine and polyoxyalkylene amines and diamines.
9 . Process according to claim 1 , wherein the lithium compound is lithium oxide (Li 2 O), lithium hydroxide (LiOH), lithium carbonate (Li 2 CO 3 ), methoxylithium (LiOCH 3 ), terbutoxylithium (LiOtBu), lithium citrate, lithium chloride (LiCl), Li-stearate (LiC 18 H 35 O 2 ), LiClO 4 , Li 2 SO 4 , LiOAc, LiOOCPh and/or lithium bromide (LiBr).
10 . Process according to claim 1 , wherein the reaction temperature is comprised between 0 and 120° C.
11 . Process according to claim 1 , wherein the amount of component (A) and component (B) are such that the molar ratio of cyclic carbonate groups to nucleophilic groups X is from 0.5 to 2.
12 . Process according to claim 1 , wherein the catalyst concentration is comprised between 0.01 and 5% by weight of the reacting mixture.
13 . Process according to claim 12 , wherein the catalyst concentration is comprised between 0.1 and 2% by weight of the reacting mixture.
14 . Process according to claim 1 , wherein the reaction is made in a solvent chosen among: alcohol, ether, ester, dimethylformamide, and water.
15 . Process according to claim 1 , wherein component (A) containing at least one cyclic carbonate compound is prepared by reaction of the corresponding epoxide compound with carbon dioxide (CO 2 ) in presence of a lithium compound as catalyst.
16 . A method of conducting a ring opening reaction wherein:
a component (A) containing at least one cyclic carbonate group having the general formula (I):
wherein:
R 2 represents a bivalent alkylene radical: —(CR 3 R 4 ) p — with p≧2,
each R 3 and each R 4 is independently chosen from: hydrogen, aromatic radical, alkyl, alkenyl which contains from 0 to 8 ether bridges, and R 3 and/or R 4 may be substituted by one or more alkyl, alkenyl, aromatic radical, hydroxyl group(s), and/or cyclic carbonate group of formula (I),
is reacted with a component (B) containing at least one reactive nucleophilic function X wherein each X is, independently, chosen from a primary amino or hydrazo, secondary amino or hydrazo, thiol, and/or oxime, in the presence of a lithium compound as catalyst
to form an organic compound (C) containing at least one unit of the general formula (II): —X—CO—O—.
17 . Process according to claim 10 wherein the reaction temperature is 50 to 80° C.