A study of the reactions of 1,3-diynes with organo-cuprates and -argentates

✍ Scribed by H. Kleijn; M. Tigchelaar; J. Meijer; P. Vermeer

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 471 KB
• Volume: 100
• Category: Article
• ISSN: 0165-0513
• DOI: 10.1002/recl.19811000910

✦ Synopsis

Abstract

1,3‐Diynes HCCCCR′ (1, R′  H or Ph) are converted by cuprates [RCuY]M′ (R  alkyl; Y  Cl, Br or R; M′  Li, MgCl or MgBr) into a mixture of [HC(CuY)C(R)CCR′]M′ (2) and [RCHC(CuY)CCR′]M′ (3). When R is n‐alkyl, adducts 2 are the major products; adducts 3 are preferentially formed when R is a branched alkyl. Organoargentates [RAgY]MgCl (R  alkyl, Y  Br or R) convert diynes 1 selectively into [RCHC(AgY)CCR′]MgCl (6). The latter regiospecific reaction has been used to prepare functionally substituted enynes RCHC(E)CCR′ (7: E  Br, I, allyl, CO~2~H) in good yields.