Pivaloyl chloride → 1-{2-[3-Chloro-4-(2,2-dimethylpropionylamino)-benzoylamino]-propionyl}-pyrrolidine-2-carboxylic acid (2-benzyloxy-5-oxo-tetrahydro-furan-3-yl)-amide

Participants

Reaction Steps

To a suspension of 98b (100 mg, 0.19 mmol) and poly(4-vinylpyridine) (200 mg) was added pivaloyl chloride (70 μL, 0.57 mmol). The resulting suspension was stirred overnight at room temperature the filtered and diluted with EtOAc (25 mL). The organic layer was washed with 10% NaHCO3 (2×25 mL), saturated NaCl (1×25 mL), dried (MgSO4), and evaporated to dryness to afford 98 mg of title compound (85% yield) after chromatography. 1H-NMR (500 MHz, 1:1 CDCl3:CD3OD) δ 1.10-1.55 (m, 3H), 1.38 (s, 9H), 1.65-2.40 (m, 4H), 2.60-3.10 (m, 2H), 3.46-3.88 (m, 2H), 4.20-4.95 (m, 5H), 5.62 (d, 0.8H), 5.78 (d, 0.2H), 7.15-8.30 (m, 8H). Analytical HPLC: 11.82 min. LC-MS (ES+): m/e=613.2 (M+H+).

Provenance & Evidence