Diisobutylaluminum hydride → Benzyl 4-formylpiperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-benzyloxycarbonyl-piperidine-4-carboxylic acid methyl ester (2.0 g, 7.2 mmol) in anhydrous toluene (20 mL) at −78° C. was added DIBAL-H (15.2 mL of a 1 M solution in hexane, 15.2 mmol, 2 eq.) in a drop-wise fashion. The mixture was stirred at −60° C. for 2 h then quenched by addition of 1 N HCl. The resulting mixture was extracted with EtOAc (3×50 mL) and the combined organic extracts were washed with saturated brine (50 mL) then dried over Na2SO4, filtered and concentrated by rotary evaporation. The crude residue was purified by flash column chromatography by eluting 9:1 toluene/EtOAc to give 1-benzyloxycarbonyl-piperidine-4-carboxaldehyde as a colorless gum (0.49 g, 2.09 mmol, 28%). 1H NMR (300 MHz, CDCl3): δ9.75 (s, 1H), 7.46 (m, 5H), 5.24 (s, 2H), 4.15 (m, 2H), 3.12 (t, 2H), 2.54 (m, 1H), 2.02 (m, 2H), 1.68 (m, 2H).

Provenance & Evidence