反応 #1091

反応方程式

methanol

2-carboxy-5-nitrobenzenesulfonic acid

thionyl chloride

→

2-methoxycarbonyl-5-nitrobenzenesulfonic acid

溶媒

DMF

反応条件

後処理

1. 1
   温度is heated
2. 2
   その他After separating off the insoluble constituents
3. 3
   ろ過by filtration
4. 4
   濃縮the filtrate is concentrated
5. 5
   その他results
6. 6
   workup.ADDITIONWhen addition
7. 7
   その他The solid which precipitates
8. 8
   ろ過is filtered off
9. 9
   その他dried

実験手順

A suspension of 190.0 g (0.77 mol) of 2-carboxy-5-nitrobenzenesulfonic acid, 10 ml of DMF and 250 ml (3.43 mol) of thionyl chloride is heated at boiling for 3 h. After separating off the insoluble constituents by filtration, the filtrate is concentrated. 200 ml (4.94 mol) of methanol are added to the residue which results. When addition is complete the reaction mixture is cooled to 0° C. The solid which precipitates is filtered off and dried. 70.9 g (35.3% of theory) of colorless, crystalline 2-methoxycarbonyl-5-nitrobenzenesulfonic acid (m.p.: 92°-94° C.) are thus obtained. By distilling off the volatile components from the mother liquor, a second fraction (62.5 g, 31.1% of theory) is obtained.

出典