反应详情

温度

-78 °C

To a cooled solution (−78° C.) of 5,5-dimethyl-4,5,6,7-tetrahydro-benzo[c]thiophene-1-carboxylic acid (2.00 g, 9.51 mmol) in THF (35 mL), tert.-butyllithium (16 mL, 1.5 M solution in pentane) is added. The mixture is stirred at −78° C. for 10 min before isopropyliodide (7.60 g, 48.7 mmol) is added. The reaction mixture is stirred at −78° C. for 3 h, then at rt for 3 d. The reaction mixture is diluted with water and extracted twice with EA. The combined organic extracts are dried over Na2SO4 and evaporated. The crude product is purified by CC on silica gel eluting with DCM/TBME 20:1 followed by prep. HPLC to give 3-isopropyl-5,5-dimethyl-4,5,6,7-tetrahydro-benzo[c]thiophene-1-carboxylic acid (500 mg) as a white solid; LC-MS: tR=1.04 min, [M+1+CH3CN]=294.16.

1. additionis added
2. waitat rt for 3 d
3. extractionextracted twice with EA
4. dry with materialThe combined organic extracts are dried over Na2SO4
5. customevaporated
6. customThe crude product is purified by CC on silica gel eluting with DCM/TBME 20:1