Triethylamine → Methyl 4-[bis(tert-butoxy)phosphorylhydroxymethyl]-N-(benzyloxycarbonyl)-D,L-phenylalaninate

Participants

Reaction Conditions

Reaction Steps

To a solution of 8 (876 mg, 2.18 mmol) in THF (22 mL) at 0° C. was added NEt3 1.22 mL, 8.74 mmol), followed by benzyl chloroformate (0.34 mL, 2.40 mmol) dropwise via syringe. The reaction was stirred at 0° C. for 0.5 hours, then diluted with Et2O (20 mL) and quenched by dropwise addition of brine (1 mL). Additional brine (20 mL) was added and the organic phase separated and combined with an Et2O extract (2×20 mL) of the residual brine. The combined Et2O was dried (MgSO4), filtered and solvent removed by rotary evaporation under reduced pressure to yield crude 9 (1.03 g, 88%). Silica gel chromatography [EtOAc/hexanes (4:3)] provided pure 9 (621 mg, 53%).

Provenance & Evidence