stirred solution of 1 deoxynojirimycin 1 100 g 0 61 mol in saturated aqueous sodium bicarbonate 1000 ml benzyl chloroformate 95 121 g 0 67 mol was added dropwise at room temperature after stirring at room temperature for 18 hr the solution was extracted once with methylene chloride 300 ml to remove any unreacted benzyl chloroformate the aqueous layer was then extracted several times with ethyl acetate to give a total of 2 5 3 liters of the extract the organic layer was then dried na 2 so 4 filtered and concentrated to give 2 a white solid 98 57 g 54 mp 101 u00b0 2 u00b0 c anal calcd for c 14 h 19 no 6 c 56 56 h 6 44 n 4 71 found c 56 33 h 6 38 n 4 58 1 h nmr cd 3 od 7 2 7 4 m 5h 5 15 s 2h 4 23 br m 1h 4 05 br d j 8 hz 1h 3 87 dd j 6 4 hz 1h 3 78 3 85 m 2h 3 70 3 78 m 2h 3 45 br d j 8 hz 1h a mixture of 2 98 5 g 0 33.