2-Methyl-3-butyn-2-ol → 4-Hydroxy-9-(3-hydroxy-3-methyl-but-1-ynyl)-4-methyl-4,5-dihydro-6-oxa-3-thia-1-aza-benzo[e]azulene-2-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of 9-Bromo-4-hydroxy-4-methyl-4,5-dihydro-6-oxa-3-thia-1-aza-benzo[e]azulene-2-carboxylic acid methyl ester (387 mg, 1.04 mmol), 2-methyl-3-butyn-2-ol (699 mg, 8.32 mmol), Pd(OAc)2 (23 mg, 0.104 mmol), CuI (39 mg, 0.208 mmol) and PPh3 (82 mg, 0.312 mmol) in Et3N (15 mL) was degassed with N2, and the mixture was stirred at 80° C. overnight. The reaction mixture was cooled to room temperature, concentrated and purified by flash column chromatography (silica gel, EtOAc in hexane from 0 to 50%) to give 4-Hydroxy-9-(3-hydroxy-3-methyl-but-1-ynyl)-4-methyl-4,5-dihydro-6-oxa-3-thia-1-aza-benzo[e]azulene-2-carboxylic acid methyl ester as a yellow solid (312 mg, 80%). LC-MS (ESI & APCI): 374.3 (M+1).

Provenance & Evidence