Format

Send to

Choose Destination
Ultrason Sonochem. 2005 Jan;12(1-2):107-14.

Dehydration reaction of hydroxenin monoacetate in carbon tetrachloride and an aliphatic alcohol under ultrasound irradiation.

Author information

1
DSM Nutritional Products, Research and Development, P.O. Box 3255, CH 4002 Basel, Switzerland.

Abstract

A new method for the preparation of an E/Z mixture of vitamin A acetate from hydroxenin monoacetate is described. This two-step reaction was studied by changing the reaction parameters (reaction temperature, ultrasound power, and reaction time) and the alcohol used. This approach consists of the dehydration reaction of hydroxenin monoacetate under ultrasound irradiation in CCl4 and an aliphatic alcohol under an inert atmosphere. The formation of small amounts of HCl from CCl4 and an aliphatic alcohol under ultrasound irradiation is followed by the dehydration reaction of hydroxenin monoacetate. An E/Z mixture of vitamin A acetate was obtained resulting in the desired pentaenes. Some ethers derivatives were also formed as by-products, isolated and characterized. Study of the reaction mechanism is also reported here.

PMID:
15474962
DOI:
10.1016/j.ultsonch.2004.06.004
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center