Triphenylphosphine → (R)-di-tert-butyl 1-((tetrahydrofuran-2-yl)methyl)hydrazine-1,2-dicarboxylate

Participants

Reaction Steps

To (R)-(tetrahydrofuran-2-yl)methanol (4.0 g, 39.2 mmol), di-tert-butyl hydrazine-1,2-dicarboxylate (3.64 g, 15.67 mmol) and triphenylphosphine (15.41 g, 58.7 mmol) in THF (100 mL) was added (E)-di-tert-butyl diazene-1,2-dicarboxylate (13.5 g, 5.87 mmol). The mixture was stirred at ambient temperature for 3 h then diluted with water and extracted with EtOAc (100 mL×2). The organic extract was washed with brine and concentrated. Purification by flash chromatography (silica gel, 5-30% EtOAc/hexane) afforded 10.2 g (82%) of (R)-di-tert-butyl 1-((tetrahydrofuran-2-yl)-methyl)-hydrazine-1,2-dicarboxylate, which was dissolved in a solution of 4M HCl in dioxane (40 mL) and stirred at ambient temperature overnight. The solvent was removed under reduced pressure and ethyl acetate (20 mL) was added with stirring. The solid precipitate was filtered, washed with ether (10 mL) and dried under vacuum to yield 7.8 g (97%) of the title compound as a white solid. 1H NMR (300 MHz, DMSO-d6) δ ppm 1.48-1.63 (m, 1H), 1.73-1.88 (m, 2H), 1.90-2.02 (m, 1H), 2.84-3.01 (m, 2H), 3.61-3.71 (m, 1H), 3.72-3.83 (m, 1H), 3.97-4.08 (m, 1H), 5.76 (br, 5H); MS (ESI) m/z 117 (M+H)+.

Provenance & Evidence