Nitrogen → (2-methyl-1-{2-[5-(4-trimethylsilanylethynyl-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carbonyl}-propyl)-carbamic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of (1-{2-[5-(4-bromo-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester (5.00 g, 11.1 mmol), TMS-acetylene (7.90 mL, 55.5 mmol) and triethylamine (4.64 mL, 33.3 mmol) in DMF (56 mL) was degassed with N2 gas for 20 minutes. To the degassed solution was added Pd(PPh3)4 (1.28 g, 1.11 mmol) and CuI (106 mg, 0.56 mmol). The pressure flask was sealed then heated at 80° C. overnight. After cooling to room temperature, the reaction was concentrated then diluted with EtOAc and washed with water. The aqueous phase was back-extracted two times then the organic phases were combined and dried over Na2SO4. After concentration, the crude material was purified by silica gel chromatography (10-80% EtOAc-hexanes gradient) to afford (2-methyl-1-{2-[5-(4-trimethylsilanylethynyl-phenyl)-1H-imidazol-2-yl]-pyrrolidine-1-carbonyl}-propyl)-carbamic acid methyl ester (3.08 g, 6.60 mmol, 59% yield). LCMS-ESI+: calc'd for C25H35N4O3Si: 467.3 (M+H+). Found: 467.1 (M+H+).

Provenance & Evidence