New and efficient procedures for the synthesis of stereodefined 2-(hetero)aryl and 2-methyl substituted alkyl 2-alkenoates having very high stereoisomeric purity
摘要:
Stereodefined 2-(hetero)aryl and 2-methyl substituted alkyl 2-alkenoates of general formula 1 and 2 have been synthesized with a high degree of stereoselectivity as well as in good overall yields starting from alkyl 2-alkynoates, 4.
Palladium-catalyzed reaction between aryl or alkenyl halides and (1-carbalkoxy-1-alkenyl)zinc iodides. A new class of unmasked β-substituted acrylate α-anion equivalents
β-substituted acrylate α-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