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Preparation and reactions of stannylated amino acids.

Hydrostannations of propargylic glycine esters with the new hydrostannation catalyst [Mo(CO)3(CNtBu)3] (MoBI3) gave rise to alpha-stannylated allylic esters in good yield and with high regioselectivity. The chelate Claisen rearrangements of these esters allow the syntheses of gamma,delta-unsaturated amino acids with a vinylstannane moiety in the side chain. The amino acids obtained can be further modified by cross-coupling with various types of electrophiles.