Improved cis selectivities of carbonyl substituted, stable phosphorus ylides
Tris(2-methoxymethoxyphenyl)phosphine was readily quaternized when treated with Me bromoacetate. The resulting phosphornium salt was deprotonated to give the corresponding ylide (2-MeOCH2OC6H4)3P+CH-CO2Me (I). I reacted with satd., unsatd., or a-alkoxy substituted aliph. aldehydes to produce a,b-unsatd. esters with moderate to excellent cis-selectivity when methanol was used as the solvent. Thus, I reacted with isobutyraldehyde in MeOH to give a 91:9 mixt. of cis- and trans-Me2CHCH:CHCO2Me. Similarly, aldehyde II gave a 95:5 mixt. of cis- and trans-ester III. [on SciFinder (R)]
1993
2
125
126
CAN 119:27671
23-17
Aliphatic Compounds
Inst. Chim. Org.,Univ. Lausanne,Lausanne,Switz.
Journal
written in English.
78-84-2 (Isobutyraldehyde); 100-73-2; 123-72-8 (Butanal); 630-19-3 (Pivalaldehyde); 7681-84-7; 10312-83-1; 63493-93-6 Role: RCT (Reactant), RACT (Reactant or reagent) (Wittig reaction of, with tris(methoxymethoxyphenyl)phosphonium ylide); 148288-39-5P Role: RCT (Reactant), SPN (Synthetic preparation), PREP (Preparation), RACT (Reactant or reagent) (prepn. and Wittig reaction of, with aldehydes); 148267-90-7P Role: RCT (Reactant), SPN (Synthetic preparation), PREP (Preparation), RACT (Reactant or reagent) (prepn. and reaction of, with base, ylide by); 1754-62-7P; 13168-99-5P; 13894-63-8P; 13894-64-9P; 19713-73-6P; 20515-15-5P; 20515-16-6P; 20664-51-1P; 25665-54-7P; 27241-17-4P; 27241-18-5P; 57539-96-5P; 75066-86-3P; 75066-87-4P; 122592-49-8P; 122592-63-6P; 132093-58-4P; 148288-40-8P Role: SPN (Synthetic preparation), PREP (Preparation) (prepn. of); 124629-80-7 (Tris(2-methoxymethoxyphenyl)phosphine) Role: RCT (Reactant), RACT (Reactant or reagent) (reaction of, with Me bromoacetate); 96-32-2 Role: RCT (Reactant), RACT (Reactant or reagent) (reaction of, with tris(methoxymethoxyphenyl)phosphine)
REVIEWED
EPFL