Process for the carbonylation of pentenenitrile
AssigneeShell Oil Company
InventorsEit Drent, Willem Wabe Jager
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Abstract
Processes to prepare 5-cyanovaleric acid or its ester are provided, by carbonylation of a pentenenitrile, wherein pentenenitrile is reacted with carbon monoxide and water and/or an alcohol in the presence of a catalyst system. The catalyst system contains: (a) a metal of Group VIII or a compound thereof, (b) a certain bidentate phosphine, arsine and/or stibine ligand, and (c) an acid having a pKa less than 3, as measured at 18° C. in an aqueous solution. ε-caprolactam is also prepared by reduction of 5-cyanovaleric acid or ester obtained above to 6-aminocaproic acid or ester, and then cyclisation of the 6-aminocaproic acid or ester to ε-caprolactam.
Claims12
A process for preparing a 5-cyanovaleric acid or its ester comprising reacting pentenenitrile with carbon monoxide and water and/or an alcohol in the presence of a catalyst system, comprising
- (a) a source of Group VIII metal, and
- (b) a bidentate phosphine ligand 1,2-bis-(di-tert-butyl-phosphinomethyl)benzene and
- (c) an acid having a pKa less than 3, as measured at 18° C. in an aqueous solution.
A process for preparing ε-caprolactam comprising:
- (i) reacting pentenenitrile with carbon monoxide and water and/or an alcohol in the presence of a catalyst system, comprising
- (a) a source of Group VIII metal,
- (b) a bidentate phosphine ligand 1,2-bis-(di-tert-butyl-phosphinomethyl)benzene and
- (c) an acid having a pKa less than 3, as measured at 18° C. in an aqueous solution thereby producing 5-cyanovaleric acid or ester,
- thereby producing 5-cyanovaleric acid or ester;
- (ii) reducing the 5-cyanovaleric acid or ester to provide 6-aminocaproic acid or ester, and
- (iii) cyclising the 6-aminocaproic acid or ester to provide ε-caprolactam.
Dependencies are inferred from the claim text.