Rhodium-Catalyzed Synthesis of Terminal Alkenes

Abstract

Terminal alkenes have been efficiently prepared via a rhodium-catalyzed olefination procedure using Wilkinson’s catalyst in the presence of triphenylphosphine, 2-propanol and trimethylsilyldiazomethane. Optimized reaction conditions are described for aldehydes and ketones, as well as alternative work up procedures.

Key words

terminal alkene - methylenation - trimethylsilyldiazomethane - triphenylphosphine - Wilkinson’s catalyst

References

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• 11b

  As trimethylsilyldiazomethane is non-explosive and non-mutagenic, the very careful operations used for the preparation of diazomethane are not necessary.

• 12 Shioiri T. Yamada S. Org. Synth.  1984,  62:  187 

10

Some bottles purchased from Aldrich contain as much as 50% of chloromethyltrimethylsilane by ¹H NMR.

13

See ref. 11 for analytical procedure.