Diisobutylaluminum hydride → 1,1-Dimethylethyl 6-chloro-4-(hydroxymethyl)-1H-indole-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

6-Chloro-indole-1,4-dicarboxylic acid 1-tert-butyl ester 4-methyl ester 13.2 g (42 mmol) is dissolved in 200 mL of dry tetrahydrofuran and cooled to −78° C. The reaction is equipped with a dropping funnel and the reaction purged with nitrogen. DIBAL-H (85 mL, 1.5 M/L 128 mmol) is added via a syringe to the dropping funnel and the reagent added over the course of 10 minutes. The reaction is stirred for 30 minutes then tested via LC/MS for completion. An additional two equivalents of DIBAL-H is added to the reaction via syringe and the reaction stirred for an additional hour. After 1 hour, the reaction is quenched by the slow addition of 500 mL of saturated Rochelle's salt, and slowly warmed to room temperature with stirring overnight. The resulting biphasic mixture is separated and the water layer extracted with DCM. The combined organic layers were dried (MgSO4) filtered and evaporated in vacuo to give the title compound that is purified on silica gel with hexanes ethyl acetate as the eluent (9.5 g 34 mmol, 80%). LCMS (ESMS): m/z 282.9 (M+H+).

Provenance & Evidence