反应详情

5.0 g. of 2-carboxy-5-oxo-5H-dibenzo[a,d]cycloheptene is dissolved in 100 ml. of chloroform, and 50 ml. of thionyl chloride and 1.0 ml. of dimethylformamide are added thereto. The mixture is left for 3 days, then evaporated to dryness to afford 2-chlorocarbonyl-5-oxo-5H-dibenzo[a,d]cycloheptene. 1.0 G. of this compound is dissolved in 10 ml. of tetrahydrofuran containing 1.0 ml. of isopentyl alcohol and 2 ml. of pyridine. The mixture is left for 24 hours, then evaporated to dryness, dissolved in 1:4 ether/hexane and filtered through silica gel, then evaporated to give isopentyl (5-oxo-5H-dibenzo[a,d]cyclohepten-2-yl)carboxylate (m.p. 26°-30° C).

1. customevaporated to dryness