1-Hydroxybenzotriazole → 7-{2-[2-(tert-Butyldimethylsilanyloxy)ethoxy]thiazol-5-yl}-6-[cyclo-propyl-(2,3-dichlorobenzyl)carbamoyl]-3,9-diazabicyclo[3.3.1]non-6-ene-3,9-dicarboxylic acid di-tert-butyl ester

Participants

Reaction Steps

A sol. of compound D4 (1.39 mmol, 0.87 g) in CH2Cl2 (11.2 mL) was treated with DMAP (0.35 mmol, 42 mg), HOBt (1.67 mmol, 0.23 g), EDC.HCl (3.47 mmol, 0.66 g), and DIPEA (5.55 mmol, 0.95 mL). After 30 min at rt, cyclopropyl-(2,3-dichlorobenzyl)-amine (prepared by reductive amination from 2,3-dichlorobenzaldeyhde and cyclopropylamine; 4.16 mmol, 0.90 g) was added and the mixture was stirred for 4 days at rt. The reaction was then diluted with CH2Cl2 (40 mL), washed with aq. 1M HCl (2×50 mL), dried over MgSO4, filtered, and the solvents were removed under reduced pressure. Purification of the residue by FC (EtOAc/heptane 30:70) yielded the title compound (0.48 g, 42%). LC-MS: tR=1.29 min; ES+: 823.50.

Provenance & Evidence