Publication Date: 2009-Jul-31
The IP.com Prior Art Database
To a mechanically stirred solution of 20.0 g (180.0 mmol) of chloroacetylchloride and 97 g (0.70 mmol) of potassium carbonate in 150 mL of tetrahydrofuran is added a solution of L-prolinamide 20.0 g (180.0 mmol) in 500 mL of tetrahydrofuran in a dropwise fashion over 45 minutes. This reaction is then mechanically stirred for an additional two hours at room temperature. The reaction is then filtered to remove potassium salts and the filtrate is dried over Na2SO4. The Na2SO4 is then removed via filtration and to this colorless filtrate is added trifluoroacetic anhydride (25.0 mL, 0.180 mmol) in one portion. The reaction is then magnetically stirred for 1 hour at room temperature and the resulting clear yellow/orange solution is concentrated via rotovap. The excess trifluoroacetic anhydride is removed by adding ethyl acetate to the concentrated oil and reconcentrating via rotovap. This removing operation is performed three times. The resulting oil is partitioned between ethyl acetate and water. The product is then extracted into the ethyl acetate and the aqueous layer is then washed twice with ethyl acetate. The combined organic layers are then washed successively with water and brine dried over magnesium sulfate, filtered and concentrated to obtain 1-chloroacetyl-2 cyanopyrrolidine as a yellow solid in 74% yield.
Tmelting: 54-57 °C
MS-ESI(m/z): 195, (MNa+), 173 (MH+).
1H-NMR (CDCl3, 300 MHz): d 2.09-2.45 (m, 4H, -NCH2CH2-), 3.47-3.69 (m, 1H, -NCHAHBCH2-), 3.70-3.80 (m, 1H, -NCHAHBCH2-), 4.02-4.25 (dd...