反应详情

A solution of tert-butyl 4-(2-bromo-5-(trifluoromethyl)phenyl)-5,6-dihydropyridine-1(2H)-carboxylate (from Step 1 of Intermediate VV; 2.435 g, 5.99 mmol) in 20 mL EtOH was treated with platinum(iv) oxide (0.136 g, 0.599 mmol) and was placed under 45 psi H2 for one hour. LC/MS showed mostly product and de-brominated product. The reaction mixture was diluted with DCM and was filtered through diatomaceous earth. The filtrate was concentrated then purified directly by column chromatography (0 to 15% EtOAc/heptane) yielding tert-butyl 4-(2-bromo-5-(trifluoromethyl)phenyl)piperidine-1-carboxylate (0.970 g, 2.376 mmol, 39.6% yield). m/z (ESI) 431.0 (M+Na)+.

1. filtrationwas filtered through diatomaceous earth
2. concentrationThe filtrate was concentrated
3. customthen purified directly by column chromatography (0 to 15% EtOAc/heptane)