Diisopropyl azodicarboxylate → HCID 117642877, compound

Participants

Reaction Steps

DIAD (1.36 mL, 6.97 mmol) was added dropwise to a stirred solution of PPh3 (76 mg, 0.30 mmol), dibenzyl phosphite (1.94 g, 6.97 mmol) and tert-butyl 3-(3-hydroxypropoxy)-2,2-dimethylpropanoate (53) (1.08 g, 4.65 mmol) [prepared using the same procedure as Example F1 steps (ii)-(iii) using 3-(benzyloxy)propyl 4-methylbenzenesulfonate in step (ii)] in THF (100 mL) at 0° C. The reaction was allowed to warm to RT and stirred for 16 h, and the volatiles were removed in vacuo. The crude product was purified by silica gel chromatography (120 g, 0-60% EtOAc in isohexane) to afford tert-butyl 3-(3-((bis(benzyloxy)phosphoryl)oxy)propoxy)-2,2-dimethylpropanoate (54) (1.76 g, 54%) as a clear colourless oil: m/z 515 (M+Na)+ (ES+). 1H NMR (400 MHz, DMSO-d6) δ: 7.40-7.35 (m, 10H), 5.07-4.96 (m, 4H), 4.04-3.92 (m, 2H), 3.39 (t, J=6.2 Hz, 2H), 3.28 (s, 2H), 1.77 (quin, J=6.2 Hz, 2H), 1.35 (s, 9H), 1.02 (s, 6H).

Provenance & Evidence