Lithium alkenyltrialkylalanate conjugate additions

Irrespective of the stereochemistry of the ot,p-enones, lithium alkenyltrialkylalanates, e.g. (28) and (29), obtainable by treatment of alkenylalanes with methyllithium (or n-butyllithium), are also excellent 1,4-conjugate alkenyl transfer reagents. The cornerstone of a general prostaglandin synthesis, as exemplified in Scheme 6, employs the alanate conjugate addition process exclusively.13... 

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