反应详情

温度

-75 °C

At −75° C. under stirring, sec-butyl-lithium (195.76 ml, 0.231 moles) and, after 1 hour, at the same temperature, dimethylformamide (53.66 ml, 0.693 moles) were added dropwise to a solution of 3-cyclopentyloxy-N,N-diethyl-4-methoxy-benzamide (61.2 g, 0.21 moles), obtained as described in example 3, and of tetramethylendiamine (34.86 ml, 0.231 moles) in anhydrous tetrahydrofuran (480 ml). After further half an hour at −75° C., the reaction mixture was poured into a pH=7 phosphate buffer, ethyl acetate and concentrated HCl. The extraction was repeated further twice with fresh ethyl acetate, then the extract was washed with 5% potassium bisulphate, then with water, then dried on sodium sulphate and evaporated to dryness. The residue was cromatographed on silica gel (eluent petrolatum/ethyl acetate 1:1) to give 23.3 g of the title compound (yield: 35%).

1. customobtained
2. waitAfter further half an hour at −75° C.
3. extractionThe extraction
4. washthe extract was washed with 5% potassium bisulphate
5. dry with materialwith water, then dried on sodium sulphate
6. customevaporated to dryness