tert-Butyl piperazine-1-carboxylate → Tert-butyl 4-(3-methoxy-2,2-dimethyl-3-oxopropyl)piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of 567 (0.57 mmol, crude in 25 ml of DCM) and 1-Boc-piperazine (1.175 g, 6.31 mmol) in DCM (50 ml) was stirred for 1 h at rt under nitrogen, then cooled down to 0° C. To the cold solution NaBH(OAc)3 (4.22 g, 18.93 mmol) was added in one portion. The reaction mixture was stirred at 0° C. for 1 h, then at rt overnight, quenched by addition of water, stirred for 1 h and slowly neutralyzed with a saturated aqueous solution of sodium bicarbonate (pH=7-8). The alkaline solution was extracted with DCM. The organic extract was dried over anhydrous magnesium sulfate, filtered and concentrated. The residue was purified by Biotage (Snap 25 g cartridge, MeOH/DCM: 0/100 to 10/90 over 30 CV), to afford the desired product 568 (1.137 g, 3.79 mmol, 60% yield) as colorless oily liquid. MS (m/z): 301.3 (M+H).

Provenance & Evidence