Trimethylenemethanepalladium complexes

Trimethylenemethane, 258, 579 Trimethylenemethanepalladium complexes, 81 N,N,P-Trimethyl-P-phenylphosphinothioic amide, 569-570 Trimethyl phosphite, 510... 

Bicyciic methy/enecyclopentanes. Trostand Chan2 have extended their synthesis of mcthylenecyclopentanes by cycloaddition of trimethylenemethanepalladium complexes to alkenes (9,454-455J3 to an intramolecular [3 + 2] cycloaddition to give bicyciic mcthylenecyclopentanes. The substrates (2) can be prepared by reaction of Ihc Grignard reagent prepared from 2-bromo-3-(trimethylsilyl)propene (1) with a suitable bifunctional aldehyde (equation I). 

The use of arylamines in the Pd"-catalysed coupling with olefins has been reported. This modification of the classical Heck procedure further extends the utility of the method. A study of the regiochemistry of the cycloaddition of substituted trimethylenemethanepalladium complexes is necessary if they are to be generally adopted in synthesis. Reaction of cyclopentenone with a methyl-substituted trimethylenemethane species afforded a single stereoisomeric product, which was converted to a precursor of the natural product chrysomelidial (Scheme 24). Since previous work on the unsubstituted system suggested a... 

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