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

Participants

Reaction Steps

To a solution of tert-butyl 4-((5-cyanobenzo[d]oxazol-2-yl)methyl)-5-methoxy-7-methyl-1H-indole-1-carboxylate (Example 144-A) (60 mg, 0.144 mmol) in THF (2.1 mL) under nitrogen at −78° C. was added LiHMDS (0.359 ml, 0.359 mmol) in THF. After 10 mins, ethyl chloroformate (0.276 mL, 2.87 mmol) was added and the reaction was warmed to room temperature. After 5 mins the reaction was quenched with sat. aq. NH4Cl, the layers were separated and the aqueous layer extracted with EtOAc. The EtOAc layer was concentrated, purified via FCC with Hep/EtOAc to obtain the title compound. MS (ESI+) m/z 490.0 (M+H).

Provenance & Evidence