反应详情

150 g of 2,3-dichlorobenzoyl cyanide are hydrogenated with elemental hydrogen under normal pressure at 70° C. in 1.5 l of glacial acetic acid and 84.15 g of acetic anhydride over 5 g of PtO2. After absorption of 112% of the calculated amount of hydrogen (time taken: c. 5 hours), the hydrogenation is discontinued, the reaction mixture is filtered and the filtrae is concentrated by evaporation. The residual yellow oil is crystallised by addition of hexane/diethyl ether. The crystalline product is isolated by filtration and dried. M.p. 107°-109° C. IR (solid/KBr) in cm-1 : 3300 (NH); 1735 (CO); 1650 (CO). 1H-NMR (CDCl3) in ppm: 2.08 (s, 3H); 4.55 (d, 2H); 6.2-6.6 (broad s, 1H); 7.25 (m, 3H).

1. customAfter absorption of 112% of the calculated amount of hydrogen (time taken: c. 5 hours)
2. filtrationthe reaction mixture is filtered
3. concentrationthe filtrae is concentrated by evaporation
4. customThe residual yellow oil is crystallised by addition of hexane/diethyl ether
5. customThe crystalline product is isolated by filtration
6. customdried