2,6-Di-tert-butylpyridine → Methyl 3-({2-[(tert-butoxycarbonyl)amino]-2-methyl-3-phenylpropoxy}methyl)-5-[(methylsulfonyl)(propyl)amino]benzoate

Participants

Reaction Steps

To a solution of tert-butyl (1-benzyl-2-hydroxy-1-methylethyl)carbamate (728 mg, 2.75 mmol) and methyl 3-(bromomethyl)-5-[(methylsulfonyl)(propyl)amino]benzoate (500 mg, 1.37 mmol) in dichloromethane (30 mL) were added silver triflate (423 mg, 1.65 mmol) and 2,6-ditertbutylpyridine polymer bound (1.53 g, 2.75 mmol, loading=1.8 mmol N/g resin, Aldrich 37, 782-1). The reaction mixture was stirred at rt in a sealed flask for 16 h. The reaction mixture was filtered on celite, rinsed with dichloromethane and MeOH, concentrated in vacuo and purified by flash chromatography (silica, 0-45% EtOAc/hexanes) to provide methyl 3-({2-[(tert-butoxycarbonyl)amino]-2-methyl-3-phenylpropoxy}methyl)-5-[(methylsulfonyl)(propyl)amino]benzoate as a white foam (intermediate xx). 1H NMR (400 MHz, CDCl3) δ 7.99 (s, 1H), 7.92 (s, 1H), 7.57 (s, 1H), 7.30-7.20 (m, 3H), 7.18-7.7.14 (m, 2H) 4.60 (s, 2H), 4.56 (s, 1H), 3.95 (s, 3H), 3.68 (t, J=6.7 Hz, 2H), 3.57 (A of AB, d, J=8.9 Hz, 1H), 3.47 (B of AB, d, J=8.9 Hz, 1H), 3.15 (A of AB, d, J=13.2 Hz, 1H), 2.94 (B of AB, d, J=13.2 Hz, 1H), 2.90 (s, 3H), 1.55-1.45 (m, 2H), 1.47 (s, 9H), 1.27 (s, 3H), 0.92 (t, J=7.3 Hz, 3H).

Provenance & Evidence