A mixture of potassium hydroxide in methanol (20.0 mL of a 4M solution ) is heated to 42° C. and treated dropwise with a mixture of N-methyl-N-nitroso-p-toluenesulfonamide (4 g, 18.7 mmol) in ether (40 mL). The diazomethane is distilled over, condensed with a dry ice/acetone condenser and collected. The diazomethane/ether solution is stirred in an ice-bath, treated dropwise with a solution of {o-[5-(2,4-dichlorophenoxy)-2-nitrophenoxy]phenoxy}acetyl chloride (1.09 g, 2.32 mmol) in tetrahydrofuran, stirred for 30 minutes and concentrated in vacuo to give the title product as a yellow oil which is identified by NMR spectral analyses.
