Mandelic Acid → 2,2'-Bifuran

Participants

Reaction Conditions

Reaction Steps

A mixture of 4.9 parts of chloranil (2:3:5:6-tetrachlorobenzoquinone), 12 parts of mandelic acid and 25 parts of trichlorobenzene is stirred for 20 hours at 180° C. The mixture is cooled to 20° C. and the precipitated solid is filtered off, washed with trichlorobenzene and then crystallised from toluene. The solid is then dissolved in chloroform, the chloroform solution extracted with a 2% aqueous solution of sodium carbonate, and the chloroform then removed by distillation. 4:8-Dichloro-3:7-diphenyl-2:6-dioxo-2:6-dihydrobenzo[1:2-b:4:5-b1 ] bifuran is obtained. The product has a melting point of 310° C.-315° C., a λ max in chloroform of 457 n.m. and a molecular extinction coefficient of 45000. The n.m.r. and mass spectra are consistent with the stated structures.

Provenance & Evidence