A new synthetic approach to investigate the potential decarbonylation protocol in polyketide synthesisvia complex N-alkoxyamines starting from 4 hydroxy TEMPO and aldehydes is investigated. The decarbonylation of aldehydes is used for generating 1,2-diols from stereodefined 1,3 diols, which have been obtained by the Evans aldol protocol.

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The stereo controlled palladium catalysed umpolung allylation of aldehydes generates two new stereogenic centres and a terminal double bond, making this reaction highly attractive for natural product synthesis.

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We could show that the allylation of a-chiral aldehydes can be performed in a highly stereoselective way in a one-pot procedure using Pd(0) catalysis. A variety of aldehydes could successfully be employed obtaining the products in moderate to good yields and promising d.r.´s.

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