Studies on ketene and its derivatives. CXVIII. Nickel- or palladium-catalyzed reaction of diketene with organometallics. Synthesis of 3-substituted 3-butenoic acids.

Abstract

The reaction of diketene (1) with some organometallics was investigated. The reaction of 1 with benzyl Grignard reagents in the presence of nickel (II) chloride afforded 3-benzyl-3-butenoic acids 2a-e. In the presence of dichloro [1, 3-bis (diphenylphosphino) propane] nickel, primary alkylmagnesium bromides reacted with 1 to give 3-methylenealkanoic acids 2g-i. (E)-1-Alkenyldiisobutylaluminiums, in the presence of Pd (0)-catalyst, reacted with 1 to give 3-methylene-4-alkenoic acids 5a-c. Similarly, alkynyl-and aryl-zinc chlorides gave 3-methylene-4-alkynoic acids 7a-d and 3-aryl-3-butenoic acids 8a-c, respectively.