(Z)-5-(2,5-dihydroxy-3,4,6-trimethylphenyl)-3-methyl-2-pentenyl acetate → (S)-3,4-dihydro-2,5,7,8-tetramethyl-2-vinyl-2H-[1]-benzopyran-6-ol

Participants

Reaction Steps

A solution of 125 mg (0.43 mmol) of (Z)-5-(2,5-dihydroxy-3,4,6-trimethylphenyl)-3-methyl-2-pentenyl acetate, 8 mg (3%) of (S)-2,2'-bis-(diphenylphosphino)-1,1'-binaphthalene and 2.3 mg (1.5%) of π-allylpalladium chloride dimer in DMSO (3 ml) was left at 60° C. for 17 hours. After cooling the mixture was diluted with water and extracted with ether. The extracts were washed with water, dried, concentrated and the residue was purified as in Experiment 1, yielding 86 mg of (S)-3,4-dihydro-2,5,7,8-tetramethyl-2-vinyl-2H-[1]-benzopyran-6-ol. O.P. 36%.

Provenance & Evidence