Abstract
Aldehyde 4 reacts in the presence of TMSOTf and an acid scavenger to provide the corresponding oxasilacycle 5 in very good yield and as a single diastereoisomer. The sense of 1,3-stereoinduction serves to introduce a 1,3-syn -diol relationship into the cyclic product. This is in accord with a previous study involving an analogous intramolecular allylation.
Key words
cyclisations - intramolecular allenylation - Lewis acids - stereoselective synthesis - Temporary Silicon Connection
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