反应详情

The same operation as in Example (36a) was performed using 2-ethyl-1,3-dithiane obtained in Example (39a) (3.51 g, 23.7 mmol), n-butyllithium (1.58 M solution in hexane, 18 mL, 28.3 mmol) and ethyl trifluoroacetate (4 mL, 33.6 mmol), to obtain 2.02 g of the title compound as a pale yellow oily substance (35%).