tert-Butanol → HCID 19100702, compound

Participants

Reaction Steps

2-t-Butoxycarbonylamino-4-ethyl-5-methylthiophene-3-carboxylic acid (34.2 g, 0.12 mol) was dissolved in 35 ml of tetrahydrofuran and 15.8 ml (21.6 g, 0.156 mol) of triethylamine, and diphenylphosphoryl azide (36.3 g, 0.132 mol) was added, whereby the temperature rose to 47° C. After 30 min at room temperature, 1200 ml of t-butanol was added, and the mixture was refluxed for seven days. The dark mixture was evaporated, dissolved in methylene chloride, washed with 54 citric acid, saturated sodium bicarbonate, treated with charcoal and evaporated to yield 55.8 g of a dark oil of crude di-t-butyl 4-ethyl-5-methylthiophene-2,3-dicarbamate which was not further purified.

Provenance & Evidence