REACTIONS OF SUBSTITUTED (2-BUTENE-1,4-DIYL)MAGNESIUM COMPLEXES WITH CARBOXYLIC ESTERS AND LACTONES - FORMATION OF A VERSATILE INTERMEDIATECAPABLE OF GENERATING SUBSTITUTED CYCLOPENTENOLS, FUSED-RING CYCLOPENTENOLS, OR BETA,GAMMA-UNSATURATED KETONES
Rd. Rieke et al., REACTIONS OF SUBSTITUTED (2-BUTENE-1,4-DIYL)MAGNESIUM COMPLEXES WITH CARBOXYLIC ESTERS AND LACTONES - FORMATION OF A VERSATILE INTERMEDIATECAPABLE OF GENERATING SUBSTITUTED CYCLOPENTENOLS, FUSED-RING CYCLOPENTENOLS, OR BETA,GAMMA-UNSATURATED KETONES, Journal of the American Chemical Society, 117(20), 1995, pp. 5429-5437
Reaction of the magnesium complexes of substituted 1,3-dienes with eit
her carboxylic esters or lactones at low temperature (-78 to -10 degre
es C) generates the magnesium salt of a cyclopropanol (4). This interm
ediate can either be trapped as an acetate of the cyclopropanol (9) or
it can be heated to yield substituted cyclopentenols. Moreover, when
this intermediate is protonated, it undergoes an intramolecular rearra
ngement to yield beta,gamma-unsaturated ketones. Accordingly, this pro
tocol allows the generation of a wide range of complex molecules from
a single intermediate in high isolated yields.