O-Cresol → 3,3,6-Trimethyl-2,3-dihydro-1H-inden-5-ol

Participants

Reaction Steps

370 g of isoprene, stabilized with 1 g of phenothiazine, were added dropwise over the course of 6 hours to a solution of 535 g of o-cresol, 63 g of 85% strength phosphoric acid and 5 ml of water in 1.2 liters of xylene at 110° C. To complete the reaction, stirring was continued overnight at 110° C. The acid phase was separated off and extracted with toluene. The combined organic phases were washed until neutral. Fractional distillation gave 270 g of 3,3,6-trimethyl-5-hydroxy-indane (boiling point: 142°-143° C/12 mm Hg; melting point: 70° - 71° C) and 179 g of 3,3,4-trimethyl-5-hydroxy-indane (boiling point: 146° C/12 mm Hg; melting point 92° - 93° C). ##STR33##

Provenance & Evidence