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Abstract: A highly regio- and stereoselective [Pd(allyl)Cl]2 catalyzed Heck reaction of aryl iodides and electronically neutral terminal olefins generated in situ by fluoride induced protiodesilylation of alkenylsilanol derivatives under mild conditions has been developed. The products, viz. terminally substituted styrenes and (E)-1,4-diaryl-1-butenes were obtained in very good yields. The dibenzylbutyrolactone lignan skeletons have been prepared employing two regio- and stereoselective Bu3SnH-mediated radical cyclization routes. [Copyright &y& Elsevier]

A stereoselective total synthesis of (+)-carpamic acid 1 has been achieved from the σ-symmetric 3-[dimethyl(phenyl)silyl]glutaric anhydride 11 featuring its asymmetric desymmetrisation using oxazolidinone 12. The dimethyl(phenyl)silyl group is not only acting as a masked hydroxy group but also stereodirects ester enolate methylation and facilitates the Curtius reaction of the β-silyl-amide 23. A highly stereoselective hydrogenation of the imine 10 is the key step in the construction of the all cis-2,3,6-trisubstituted piperidine. [Copyright &y& Elsevier]