1,5-Asymmetric induction of chirality: highly diastereoselective synthesis of homoallylic tertiary alcohols by the Lewis acid-mediated addition of allylstannanes into ketones in the side-chain of π-allyltricarbonyliron lactone complexes
Abstract
Allylstannanes add into ketone groups in the side-chain of π-allyltricarbonyliron lactone complexes to afford the corresponding homoallylic tertiary alcohol complexes with very high levels of diastereocontrol. The reaction provides an example of 1,5-asymmetric induction of chirality with the lactone tether acting as the source of induction. The endo addition complexes can be converted into (E,E)-dienes bearing an α tertiary alcohol chiral centre in two steps proceeding via the η4-dienetricarbonyliron complexes. No loss of enantio- or diastereo-purity is observed during decomplexation.