反应详情

Heat a mixture of 5-chloro-3H-benzothiazol-2-one (9.3 g, 50 mmol), nickel(II) bromide (10.9 g, 50 mmol) and sodium cyanide (4.91 g, 100 mmol) in 1-methyl-pyrrolidinone (100 mL) in a microwave reactor 5 to 200° C. over 15 min and hold 1 h. Filter the cooled mixture through a glass frit, add diethyl ether and brine and filter again. Wash the organic phase with brine three times and concentrate in vacuo. Pass the residue through a plug of silica gel eluting with hexane/EtOAc (2:1) and then dichloromethane/methanol (9:1) to obtain the desired intermediate (3.2 g, 36%). MS (ES+) m/z: 177 (M+H)+.

1. temperatureHeat
2. filtrationFilter the cooled mixture through a glass frit
3. additionadd diethyl ether and brine
4. filtrationfilter again
5. washWash the organic phase with brine three times
6. concentrationconcentrate in vacuo