2,4-DIFLUORO-5-NITROBENZENESULFONYL CHLORIDE synthesis

Yield:1780-83-2 81%

Reaction Conditions:

with chlorosulfonic acid at 100; for 48 h;

Steps:

9.1

Step 1. 2,4-difluoro-5-nitrobenzenesulfonyl chlorideA mixture of 2, 4-difluoro-1 -nitrobenzene (20 g, 126 mmol) in chlorosulfonic acid (44 g, 378 mmol) was stirred at 100 °C for 48 hours before being poured into ice-water and extracted with EtOAc. The organic extract was dried (Na₂S0₄) and concentrated, and the residue was triturated with 10% EtOAc-petroleum ether to give 2,4-difluoro-5- nitrobenzenesulfonyl chloride as a brown oil (21 g, 81 %) which was used directly in the next step.

References:

WO2011/56740,2011,A1 Location in patent:Page/Page column 36