Stereochemistry of the addition products of phenoxide and cresoxide ions to methyl 3-arylpropynoates

摘要

The reaction of methyl 3-arylpropynoates 1a-e with phenoxide and p-cresoxide ions in DMF gives mixtures of Z- and E-methyl 3-aryl-3-aryloxypropenoates 2a-e and 3a-e, respectively, whereas the reaction of 1c,d (R=Br, Cl) with phenoxide ion in MeOH gives exclusively the Z-adducts 2c,d. The configurational assignments of the adducts are based on the ~1H NMR study. The effect of solvent and the nature of nucleophile on Z/E ratio has been discussed.