1026720-36-4Relevant articles and documents
Reaction of magnesium alkylidene carbenoids with lithium α-sulfonyl carbanions: A novel synthesis of tri- and tetra-substituted allenes from 1-chlorovinyl p-tolyl sulfoxides and sulfones
Satoh, Tsuyoshi,Sakamoto, Tatsuya,Watanabe, Masanori,Takano, Koji
, p. 966 - 970 (2003)
Treatment of 1-chlorovinyl p-tolyl sulfoxides, which were synthesized from ketones and chloromethyl p-tolyl sulfoxide, with ethylmagnesium chloride or isopropylmagnesium chloride at below -78°C gave magnesium alkylidene carbenoids in about 90% yields. The reaction of the generated carbenoids with lithium α-sulfonyl carbanions was found to afford tri- and tetra-substituted allenes. Both cyclic ketones and acyclic ketones were useful in this procedure. However, the 1-chlorovinyl p-tolyl sulfoxides derived from aldehydes gave only rearranged products, acetylenes, under the reaction conditions. The magnesium alkylidene carbenoid derived from an optically active 1-chlorovinyl p-tolyl sulfoxide was treated with lithium α-carbanion of 1-naphthyl phenyl sulfone; however, the obtained allene was found to be racemic. The mechanism of this reaction is also discussed.
