Hydrochloric Acid → Biphenyl-2-ylcarbamic Acid 1-[2-(5-(Benzyl-[(R)-2-(8-benzyloxy-2-oxo-1,2-dihydroquinolin-5-yl)-2-(tert-butyldimethylsilanyloxy)ethyl]amino}-pentylcarbamoyl)ethyl]piperidin-4-yl Ester

Participants

Reaction Conditions

Reaction Steps

A mixture of the product of step (e) (3.68 g, 10 mmol) and N,N-dimethylformamide (50 mL) was heated at 60° C. until the solid completely dissolved and then cooled to room temperature. The product of step (d) (6 g, 10 mmol) and diisopropylethylamine (3.5 mL) was added and the reaction mixture was cooled to 0° C. PyBOP (6.25 g, 12 mmol) was added in one portion and the reaction mixture was stirred at 0° C. to room temperature for 2 hours. The reaction mixture was then poured into cold water (500 mL) with stirring and the pH of the resulting mixture was adjusted to about 2 using aqueous 1 M hydrochloric acid. This mixture was stirred for 15 min and then filtered to collect the solid, which was washed with water (100 mL) and dried to afford the title compound (8.7 g, HPLC purity >95%) as an off-white solid.

Provenance & Evidence