Unusual Regioselectivity in the Opening of Epoxides by Carboxylic Acid Enediolates

Molecules

Luis R. Domingo²  Salvador Gil²  Margarita Parra¹ 

[1]Department of Organic Chemistry, Universitat de València, Dr. Moliner 50, 46100 Burjassot, Spain. Fax [phone]

[2] E-mails

关键词: Lactones;    lithium chloride;    nucleophilic addition;    regioselectivity;    diastereoselectivity;   

DOI  :  10.3390/molecules13061303

来源: mdpi

【 摘 要 】

Addition of carboxylic acid dianions appears to be a potential alternative to the use of aluminium enolates for nucleophilic ring opening of epoxides. These conditions require the use of a sub-stoichiometric amount of amine (10% mol) for dianion generation and the previous activation of the epoxide with LiCl. Yields are good, with high regioselectivity, but the use of styrene oxide led, unexpectedly, to a mixture resulting from the attack on both the primary and secondary carbon atoms. Generally, a low diastereoselectivity is seen on attack at the primary center, however only one diastereoisomer was obtained from attack to the secondary carbon of the styrene oxide.

【 授权许可】

CC BY   
© 2008 by the authors; licensee Molecular Diversity Preservation International, Basel, Switzerland.