Chlorotrimethylsilane → HCID 178520628, compound

Participants

Reaction Conditions

Reaction Steps

Butylphosphinic acid (2.0 g, 16 mmol) in 80 mL of dry dichloromethane was cooled to 0° C. under an atmosphere of nitrogen. Triethylamine (6.7 g, 66 mmol) was added followed by trimethylsilyl chloride (58 mL, 58 mmol, 1.0 M in dichloromethane). The mixture was stirred at 0° C. for 10 minutes and dibenzyl 2-methylenepentanedioate (2)(6.4 g, 20 mmol) in 20 mL of dichloromethane was added. The cold bath was removed and the reaction warmed to room temperature and stirred overnight. The mixture was then cooled to 0° C. and quenched by the slow addition of 5% hydrochloric acid. The dichloromethane layer was then removed and washed with 5% hydrochloric acid and with brine. The organic layer was dried (MgSO4) and evaporated to give a clear light golden liquid. The liquid was purified by flash chromatography and eluted with 3:1 hexane/ethyl acetate containing 5% acetic acid. The desired fractions were combined and evaporated to give butyl[2,4-di(benzyloxycarbonyl)butylphosphinic acid (3,R=n-butyl, R1=H) (2.9 g, 40%) as a clear and colorless oil. Rf0.12 (3:1, Hex./EtOAc 5% AcOH). 1H NMR (d6-DMSO): 7.3 ppm (m, 10), 5.0 ppm (s,4H), 2.7 ppm (m, 1H) 2.3 ppm (y, 2H), 1.8 ppm (m, 2H), 1.3 ppm (m, 4H), 0.8 ppm (t, 3H)

Provenance & Evidence