Benzyl Alcohol → Benzyl (1R,3S,4S)-4-[(tert-butoxycarbonyl)amino]-3-hydroxy-5-phenyl-1-[4-(2-pyridinyl)benzyl]pentylcarbamate

Participants

Reaction Conditions

Reaction Steps

A solution of the product from Example 1B (11.3 g, 18.7 mmol) in toluene (190 mL) was treated with DPPA (8.1 mL, 37.6 mmol) and triethylamine (5.2 mL, 37.3 mmol), heated at reflux for 2 hours, treated with benzyl alcohol (5.8 mL, 56.0 mmol), heated at reflux for an additional 16 hours, cooled to 25° C. and concentrated. The residue was treated with a solution of tetrabutylammonium fluoride in THF (94 mL, 1N), stirred at 25° C. for 40 hours and concentrated. The mixture was partitioned between ethyl acetate and water. The organic phase was washed with brine, dried over MgSO4, filtered and concentrated. The residue was chromatographed on silica gel eluting with 50% ethyl acetate in chloroform to give 2.6 g (23% yield) of the higher Rf product by TLC (35% ethyl acetate in dichloromethane).

Provenance & Evidence