3-Bromopropionic acid → 3-[2-bromo-3-cyclohexyl-6-(methoxycarbonyl)-1H-indol-1-yl]propanoic acid

Participants

Reaction Steps

3.5 eq of NaH (60% dispersion in mineral oil) was added to a solution of methyl 2-bromo-3-cyclohexyl-1H-indole-6-carboxylate (prepared as described in published International patent application WO 2004/087714, from commercially available methyl indole-6-carboxylate) in DMF (0.2 M) and the solution allowed to stir at RT for 1 h. Then 1.1 eq of 3-bromopropanoic acid were added and the mixture stirred at RT for 2 h. DMF was concentrated in vacuo and the residue taken up in EtOAc. The organic phase was washed with 1 N HCl and then brine before being dried over Na2SO4, filtered and the solvent evaporated in vacuo. The title compound was used crude in the next step; MS (ES+) m/z 408 (M+H)+, m/z 410 (M+H)+

Provenance & Evidence