Pyridine → 3,4-Dihydro-2,2-dimethyl-4-[2-oxo-3-(phenylmethyl)-1-imidazolidinyl]-2H-1-benzopyran-6-carbonitrile

Participants

Reaction Steps

To a solution of N-(6-cyano-2,2-dimethyl-3,4-dihydro-2H-1-benzopyran-4-yl)-N'-benzylethylenediamine (0.91 g, 2.71 mmole, from Example 22, part A) and 4-nitrophenyl chloroformate (0.57 g, 2.85 mmole) in methylene chloride (22.5 ml) cooled to 0° C. was added pyridine (0.27 g, 3.39 mmole ). The reaction mixture was stirred at room temperature for 24 hours, diluted with methylene chloride and washed with 5% aqueous HCl solution, 2N NaOH solution and saturated NaCl solution. The extract was dried over MgSO4 and evaporated in vacuo to obtain 1.32 g of an orange gum. The crude product was chromatographed on silica eluting with hexane/ethyl acetate (3:2) to obtain 0.65 g (66%) of the title compound as a colorless amorphous solid, m.p.=45°-48° C. 1H NMR (CDCl3) δ7.51-7.39 (m, 7H), 6.9 3 (d, J=9.38 Hz, 1H), 5.43 (dd, J=7.03 and 11.14 Hz, 1H), 4.55 (m, 2H), 3.36-3.20 (m, 3H), 3.05 (m, 1H), 1.99 (m, 2H), 1.59 (s, 3H), 1.45 (s, 3H); 13C (CDCl3) δ160.77, 158.29, 136.70, 132.49, 1 31.66, 128.60, 128.03, 127.48, 121.38, 119.16, 1 18.61, 103.29, 76.94, 48.17, 45.15, 41.90, 37.26, 34. 96, 34.67, 29.75, 24.01; MS: (M+H)+ 169 362.

Provenance & Evidence