(S)-1-Boc-3-methylpiperazine → tert-butyl (3S)-4-[2-hydroxy-5-(trifluoromethyl)-2,3-dihydro-1H-inden-1-yl]-3-methylpiperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-(trifluoromethyl)-6,6a-dihydro-1aH-indeno[1,2-b]oxirene (1.2 g, 6.0 mmol) and tert-butyl (3S)-3-methylpiperazine-1-carboxylate (1.4 g, 7.2 mol) in ethanol (20 mL) was refluxed overnight. Another gram of tert-butyl (3S)-3-methylpiperazine-1-carboxylate was added. The mixture was transferred into a sealed flask and heated to 95° C. for 2 days. The solvent was concentrated and the residue was purified by flash chromatography eluting with 25% EtOAc/hexane, followed by 5% MeOH/EtOAc+0.5% concentrated NH4OH. Two isomers were isolated. Isomer 1 (fast moving isomer): 0.45 g; MS calculated for the C20H27F3N2O3 (M+H)+401; found 401.1. Isomer 2 (slow moving isomer): 0.38 g; MS found 401.1.

Provenance & Evidence