Methyl 2-(triphenyl-lambda~5~-phosphanylidene)propanoate → (E)-2,6-dimethyl-9-phenyl-2,6-nonadienoic acid methyl ester

Participants

Reaction Steps

FIG. 24 depicts the preparation of (E)-9-phenyl-2,6-dimethyl-2,6-nonadienyl]-1-oxy-(tert.-butyl)dimethyl-silane (compound 43). In a coupling reaction hydrocinnamaldehyde (81) was converted to 2-methyl-5-phenyl-1-penten-3-ol (compound 82, CAS-No. 1836-38-0), from which (E)-4-methyl-7-phenyl-4-heptenoic acid ethyl ester (compound 83, CAS-No. 76620-37-6) was obtained. Reduction yielded (4E)-4-methyl-7-phenyl-4-heptenal (compound 84, CAS-No. 238736-71-5), which was transformed to (E)-2,6-dimethyl-9-phenyl-2,6-nonadienoic acid methyl ester (compound 85) in a Wittig-reaction using [1-(methoxycarbonyl)ethylidene]triphenylphosphorane (CAS-No. 2605-68-7). Reduction of compound (85) yielded (2E,6E)-2,6-dimethyl-9-phenyl-2,6-nonadien-1-ol (compound 86, CAS-No. 238736-72-6). Reaction with (tert.-butyl)dimethyl-silylchloride resulted in the formation of compound (43).

Provenance & Evidence