METHOD FOR PREPARING 3-CARBAMOYMETHYL-5-METHYLHEXANOIC ACID IN RECYCLING WAY

Title:

METHOD FOR PREPARING 3-CARBAMOYMETHYL-5-METHYLHEXANOIC ACID IN RECYCLING WAY

Document Type and Number:

WIPO Patent Application WO/2016/062212

Kind Code:

A1

Abstract:

The present invention provides a method for recycling 3-carbamoymethyl-5-methylhexanoic acid from a 3-carbamoymethyl-5-methylhexanoic acid chiral resolution mother liquor. The method comprises the following steps: (a) distilling the 3-carbamoymethyl-5-methylhexanoic acid chiral resolution mother liquor, adding aromatic hydrocarbon, performing heating for dissolution, and preserving heat with stirring; (b) after the heat preservation reaction in step (a) is completed, cooling the product solution to 30-60ºC, then adding dropwise alkali liquor, and performing heat preservation reaction; and (c) after the heat preservation reaction in step (b) is completed, cooling the product solution to 20-30ºC, performing demixing, adjusting the pH of a demixed water layer to 1 to 2, performing extraction by using an organic solvent, distilling an organic phase under a reduced pressure, and performing crystallization at 0±5ºC to obtain 3-carbamoymethyl-5-methylhexanoic acid. The method provided in the present invention is convenient to operate, and the recycled product is high in purity (≥99.8%) and is high in yield.

Inventors:

WANG SHUDONG (CN)
YOU XUEHAI (CN)
ZHANG WENLING (CN)

Application Number:

PCT/CN2015/091836

Publication Date:

April 28, 2016

Filing Date:

October 13, 2015

Export Citation:

Click for automatic bibliography generation Help

Assignee:

ZHEJIANG HUAHAI PHARM CO LTD (CN)

International Classes:

C07C233/05; C07C231/24

Domestic Patent References:

WO2011077463A1	2011-06-30
WO1996038405A1	1996-12-05

Foreign References:

CN104356016A	2015-02-18
CN103980144A	2014-08-13
CN104086439A	2014-10-08
CN101500985A	2009-08-05

Other References: