反应详情

N,N-dimethylglycine hydrazide hydrochloride (50 g, 0.263 mol) was stirred for 5 min in EtOH (525 mL). To this suspension was added Cs2CO3 (62.5 g, 0.192 mol) and the mixture was stirred at room temperature for 15 min. Methyl isothiocyanate (19.25 g, 0.263 mol) in EtOH (270 mL) was added to the pot and the reaction mixture was brought to reflux. The reflux condenser was removed and the EtOH was allowed to evaporate under atmospheric pressure (oil bath temperature 105-110° C.) over 3H to give a purple paste. The reaction was removed from heat and allowed to sit at room temperature overnight (18H), during which time the paste became a solid. The solid was mixed with CH2Cl2 (1.5 L) and filtered. The organic filtrate was concentrated under reduced pressure to give 31 g of a crude yellow oil. The oil was purified by column chromatography through silica gel, eluting with 4:1 CH2Cl2/MeOH to afford 15.3 g (34.9%) of the desired product. 1H NMR (DMSO-d6) d 2.17 (s, 6H) 3.46 (s, 5H) 13.57 (s, 1H). MS (APCI) calcd for C6H12N4S: 172.25; found (M−H+) 171.1.

1. temperatureto reflux
2. customThe reflux condenser was removed
3. customto evaporate under atmospheric pressure (oil bath temperature 105-110° C.) over 3H
4. customto give a purple paste
5. customThe reaction was removed
6. temperaturefrom heat
7. waitto sit at room temperature overnight
8. additionThe solid was mixed with CH2Cl2 (1.5 L)
9. filtrationfiltered
10. concentrationThe organic filtrate was concentrated under reduced pressure
11. customto give 31 g of a crude yellow oil
12. customThe oil was purified by column chromatography through silica gel
13. washeluting with 4:1 CH2Cl2/MeOH