反应详情

To a 50 ml volume three-necked flask, 1-methylsulfonyl-2-propanone (7-2-1) (2.01 g), methanol (10 ml) and benzylhydrazine monohydrochloride (14-c) (2.56 g) were added under a nitrogen atmosphere at room temperature, then additional methanol (10 ml) was added. The resulting reaction mixture was stirred at room temperature for three days, and filtered to give the primary crystal. The filtrate was concentrated under reduced pressure, and filtered again to give the crystal. The crystal was combined with the primary crystal to give 4.2 g of 1-benzyl-2-(1-methylsulfonyl-2-propylidene)hydrazine monohydrochloride (5-2-3). Additionally, the hydrochloride (5-2-3) (0.28 g) was dissolved in saturated aqueous sodium hydrogen carbonate solution (5.0 ml), and extracted with tert-butyl methyl ether (5.0 ml) 2 times. Then, the organic layer was concentrated under reduced pressure to give 0.22 g of 1-benzyl-2-(1-methylsulfonyl-2-propylidene)hydrazine (5-2-3′). NMR data of Compound (5-2-3′) is shown below.

1. extractionextracted with tert-butyl methyl ether (5.0 ml) 2 times
2. concentrationThen, the organic layer was concentrated under reduced pressure