Chelat‐kontrollierte diastereoselektive Addition an α,ß‐Epoxy‐Aldehyde

Chelate‐Controlled Diastereoselective Addition to α,β‐Epoxy Aldehydes LiClO4‐mediated reaction of trans‐substituted α,β‐epoxy aldehydes 1 with allyltributyltin (2) or trimethylsilyl cyanide provides a general method for the synthesis of the corresponding syn‐alcohols 3 with high selectivity. In the case of cis‐substituted α,β‐epoxy aldehydes the selectivity depends on the size of the substituents.