Diisopropylethylamine → 4(4-{[4-Cyano-1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazole-2-carbonyl]-amino}-3-cyclohept-1-enyl-phenyl)-piperidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

A solution of 108 mg (0.292 mmol) 4-(4-amino-3-cyclohept-1-enyl-phenyl)-piperidine-1-carboxylic acid tert-butyl ester (as prepared in the previous step) in 10 mL CH2Cl2 was treated with 97.9 mg (0.321 mmol) 4-cyano-1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazole-2-carboxylate potassium salt (as prepared in Example 1, step (d)), 204 mg (0.437 mmol) PyBrOP, and 152 μL (0.874 mmol) DIEA and stirred at RT for 17 h. The mixture was diluted with CH2Cl2 (20 mL) and washed with saturated NaHCO3 (1×15 mL) and water (1×15 mL). The organic layer was dried (MgSO4) and concentrated in vacuo. Silica gel chromatography of the residue on a Varian MegaBond Elut 50-gm column with 10-25% EtOAc-hexane afforded 160 mg (88%) of the title compound as an off-white solid: Mass spectrum (ESI, m/z): Calcd. for C30H42N5O4Si, 563.3 (M−C4H9+2H), found 563.9.

Provenance & Evidence