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

Participants

Reaction Steps

A solution of 106 mg (0.3 mmol) of (E)-5-(2,5-dihydroxy-3,4,6-trimethylphenyl)-3-methyl-2-pentenyl benzoate, 5 mg (3%) of (R)-6,6'-dimethyl-2,2'-bis-(diphenylphosphino)-1,1'-biphenyl and 1.7 mg (1.5%) of π-allylpalladium chloride dimer in 5 ml of THF was heated to 70° C. for 24 hours. After cooling the solvent was removed and the residue was Purified as described in Experiment 1, yielding 39 mg of (S)-3,4-dihydro-2,5,7,8-tetramethyl-2-vinyl-2H-[1]-benzopyran-6-ol. O.P. 56%.

Provenance & Evidence