Methyl isobutyrate → 1,1-Dimethylethyl (2R,6S)-4-({4-[1,1-dimethyl-2-(methyloxy)-2-oxoethyl]phenyl}methyl)-2,6-dimethyl-1-piperazinecarboxylate

Participants

Reaction Steps

A solution of methyl 2-methylpropanoate (188 ul, 1.64 mmol) in toluene (3 ml) was added to lithium dicyclohexylamide (362 mg, 1.93 mmol) under glove bag conditions. The suspension was stirred for 10 mins then added to a mixture of D43 (570 mg, 1.49 mmol) and bis(dibenzylideneacetone) palladium (0) (43 mg, 0.074 mmol). Tri(tert-butyl)phosphine (18 ul, 0.074 mmol) was added and the reaction mixture stirred at room temperature overnight. The solvent was removed in vacuo and chromatography eluting with 0-90% EtOAc/petroleum ether gave the title compound as a yellow oil (395 mg). δH (CDCl3, 250 MHz) 7.29 (4H, m), 4.07 (2H, m), 3.66 (3H, s), 3.46 (2H, s), 2.61 (2H, m), 2.12 (2H, dd), 1.58 (6H, s), 1.46 (9H, s), 1.29 (6H, d). MS (ES): MH+ 405.

Provenance & Evidence