Results Preparation and Pyrolysis of lY2: 3, 4-Dibenzotropilidene (8). 1, 2: 3, 4- Dibenzotropilidene (8) was prepared by the reactions shown in Scheme I. 596 The sequence for preparation of alcohol ll was the same as that in the literature. 6@ Although 1, 2: 3, 4-dibenzotropilidene (8) has been prepared previously by other methods, 7i8 we prepared it by refluxing the alcohol (1 1) with p-toluenesulfonyl chloride in pyridine. Two ...