Ethyl Acrylate → (+/-)-tert-Butyl 4-(1-(5-cyanobenzo[d]oxazol-2-yl)-4-ethoxy-4-oxobutyl)-5-methoxy-7-methyl-1H-indole-1-carboxylate

Participants

Reaction Steps

A solution of tert-butyl 4-((5-cyanobenzo[d]oxazol-2-yl)methyl)-5-methoxy-7-methyl-1H-indole-1-carboxylate (Example 144-A) (189 mg, 0.453 mmol) in THF (1.7 mL) was added to a solution of potassium tert-butoxide (50.8 mg, 0.453 mmol) in THF (1.7 mL) under nitrogen at −78° C. After stirring for 15 min a solution 18-crown-6 (11.97 mg, 0.045 mmol) in THF (566 μl) was added to the mixture at the same temperature and the reaction was then stirred for another 15 min. At this point ethyl acrylate (61.5 μl, 0.679 mmol) in THF (566 μl) was added dropwise. After 25 minutes, the reaction mixture was poured into a solution of saturated ammonium chloride, extracted with EtOAc (2×), passed through a phase separator and concentrated and purified via FCC with Heptane/AcOEt (100/0 to 70/30) to afford the title compound. MS (ESI+) m/z 418.4 (M+H-Boc).

Provenance & Evidence