反应详情

温度

-20 °C

To a solution of 2-cylohexen-1-ol (16) (18 g, 0.183 mol) in dry dichloromethane (275 ml) DBU (41.88 g, 0.275 mol) was added and the mixture was cooled to −20° C. To this solution, trichloroacetonitrile (47.66 g, 0.330 mol) was added dropwise. The reaction was stirred for 3 h at −20° C. and quenched with aqueous ammonium chloride solution. The organic phase was separated and dried over potassium carbonate. The solvent was removed under vacuum to yield the intermediate cyclohex-2-en-1-yl 2,2,2-trichloroethanimidoate. This was dissolved in toluene (100 ml) and treated with potassium carbonate (30 g). The mixture was refluxed for 12 h. After cooling the mixture was filtered through Celite and the filtrate was evaporated to afford 9 g (20%) of (22) as a solid. LC/MS: Mass found (m/z, MS, 242.9) Method: A—0.1% HCOOH, B—ACN (70%), Flow-0.8 ml/min Column: GENESIS C18 50X4.6 mm 3 U, Rt (min): 1.645: 1H NMR (CDCl3, 400 MHz) δ 1.64-1.74 (3H, m), 1.96-2.12 (3H, m), 4.46-4.47 (1H, m), 5.64-5.67 (1H, m), 5.97-5.6.01 (1H, m), 6.59 (1H, bs).

1. customquenched with aqueous ammonium chloride solution
2. customThe organic phase was separated
3. dry with materialdried over potassium carbonate
4. customThe solvent was removed under vacuum