REACTIVITY OF ALLYLIC DIMETALLIC ZINC REAGENTS .1.

Allylic 1,1-dimetallic species 2, prepared in situ from the propargylic ether 1, are multicoupling reagents. They were allowed to react in a one-pot maction, with a large variety of electrophiles E1-carbonyl compounds (acyl chlorides, aldehydes, ketones, phenyl isocyanate, methyl chloroformate), alkyl bromides, and an amino ether-and then E2-acidic water, iodine, aryl or vinyl iodide in the presence of palladium(0). The isolated yields, based on 1 (5 steps), are fair to good in most cases. The first attack (E1) always occurs on the carbon atom alpha to the oxygen; the second attack (E2) is regio- and stereoselective on the carbon atom a to the TMS moiety.