Diethyl Ether → 5-(3,3-Dimethyl-but-1-ynyl)-3-[(4-methyl-cyclohexanecarbonyl)-(1-oxa-spiro[2.5]oct-6-yl)-amino]-thiophene-2-carboxylic acid methyl ester

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Reaction Steps

NaH (140 mg of a 60% oil dispersion, 3.50 mmol) was added in portions to a solution of trimethylsulfoxonium chloride (452 mg, 3.51 mmol) in DMSO (8.0 mL) at room temperature. After 15 min, a solution of 5-(3,3-dimethyl-but-1-ynyl)-3-[(4-methyl-cyclohexanecarbonyl)-(4-oxo-cyclohexyl)-amino]-thiophene-2-carboxylic acid methyl ester (1.34 g, 2.93 mmol) in THF (8.0 mL) was added dropwise. After 3 h, brine was added and the reaction extracted with ethyl acetate. The combined organic layers were washed with water, brine, dried over Na2SO4 and concentrated to give a viscous yellow oil. Trituration with ethyl ether and hexanes provided 5-(3,3-dimethyl-but-1-ynyl)-3-[(4-methyl-cyclohexanecarbonyl)-(1-oxa-spiro[2.5]oct-6-yl)-amino]-thiophene-2-carboxylic acid methyl ester (509 mg, 37%) as a colorless solid.

Provenance & Evidence