Aluminium lithium hydride → 1,1-Dimethylethyl 5-(3-hydroxy-1-propen-1-yl)-1H-indole-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 5-(2-methoxycarbonyl-vinyl)-indole-1-carboxylic acid tert-butyl ester (4.64 g, 15.3 mmol, 1.0 eq.) in THF (87 mL) at −30° C. was added LiAlH4 (I N in THF, 18.6 mL, 1.2 eq.) by syringe pump over 20 nm in and the resulting mixture was stirred and warmed to −5° C. After cooling back to −30° C., the reaction was then quenched by slow addition of acetone (10 mL) keeping temperature below −15° C., poured into Rochelle salt at 0° C., stirred for 1 h and the separated aqueous layer was extracted with EtOAc. The combined organic phase was dried over sodium sulfate, filtered and concentrated. The residue was purification by column chromatography (methylene chloride to 2% acetone/methylene chloride) to give 5-(3-hydroxy-propenyl)-indole-1-carboxylic acid tert-butyl ester (2.89 g, 70%) or similarly 6-(3-hydroxy-propenyl)-indole-1-carboxylic acid tert-butyl ester.

Provenance & Evidence