Unmasked beta-substituted acrylate alpha-anion equivalents have been directly and very efficiently prepared by insertion of zinc metal into the carbon-iodine bonds of alkyl (E)- or (Z)-2-iodo-2-alkenoates, (E)- or (Z)-(4), respectively. The stereoisomeric composition of these new reagents, 12, depends on the experimental conditions used for their preparation. Their Pd0-catalyzed reaction with alkenyl or aryl halides, which can contain functional groups, leads chemoselectively to the corresponding cross-coupled products in high yields. When the reagents 12 are synthesized from compounds (Z)-4 or long reaction times are used for their preparation, their cross-coupled products result are rich in the stereoisomers with trisubstituted double bonds of (E)-configuration.
|Autori:||ROSSI R; CARPITA A; BELLINA F; COSSI F|
|Titolo:||PALLADIUM-CATALYZED REACTION BETWEEN ARYL OR ALKENYL HALIDES AND (1-CARBALKOXY-1-ALKENYL)ZINC IODIDES - A NEW CLASS OF UNMASKED BETA-SUBSTITUTED ACRYLATE ALPHA-ANION EQUIVALENTS|
|Anno del prodotto:||1993|
|Digital Object Identifier (DOI):||10.1016/0022-328X(93)83005-G|
|Appare nelle tipologie:||1.1 Articolo in rivista|