Methyl N-(triethylammoniosulfonyl)carbamate → 2-Ethyl-4-[5-(3-ethyl-5,5-dimethyl-4,5,6,7-tetrahydro-benzo[c]thiophen-1-yl)-[1,3,4]oxadiazol-2-yl]-6-methyl-pyridine

Participants

Reaction Conditions

Reaction Steps

A mixture of crude 3-ethyl-5,5-dimethyl-4,5,6,7-tetrahydro-benzo[c]thiophene-1-carboxylic acid N′-(2-ethyl-6-methyl-pyridine-4-carbonyl)-hydrazide (289 mg, ca. 0.48 mmol) and Burgess Reagent (367 mg, 1.6 mmol) in THF (5 mL) is heated at 110° C. for 3 min in a microwave oven. The mixture is diluted with EA (50 mL) and extracted with 1M aq. NaOH (2×10 mL). The organic phase is dried (MgSO4), filtered and evaporated. The residue is purified by HPLC to give 2-ethyl-4-[5-(3-ethyl-5,5-dimethyl-4,5,6,7-tetrahydro-benzo[c]thiophen-1-yl)-[1,3,4]oxadiazol-2-yl]-6-methyl-pyridine (53 mg); LC-MS: tR=0.96 min, [M+1]=382.26.

Provenance & Evidence