Process for the preparation of E-caprolactam
US5717089A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Mar 15, 1996 |
| Grant date | Feb 10, 1998 |
| Priority date | — |
| Expiry date | Mar 15, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D201/08
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Process for the preparation of .epsilon.-caprolactam starting from an aldehyde compound comprising at least one member from among 5-formylvaleric acid, ester or amide in which the aldehyde compound is allowed to react in the presence of ammonia and hydrogen and a subsequent cyclization of the reaction products thus formed (.epsilon.-caprolactam-precursors) to .epsilon.-caprolactam is performed in the presence of water, involved the combination of steps PA1 (a) contacting the 5-formylvaleric acid, ester or amide with ammonia and water under non-hydrogenation conditions, PA1 (b) contacting the resulting mixture of step (a) with hydrogen in the presence of ammonia under hydrogenation conditions, wherein the water content is greater than 10 wt. %, PA1 (c) heating the resulting mixture of step (b) at a temperature between 200.degree. and 350.degree. C. in order to convert the reaction products of step (b) to .epsilon.-caprolactam.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.