Yield:77055-30-2 81%

Reaction Conditions:

with nitronium tetrafluoborate in acetonitrile at -30 - -15;

Steps:

XL 5-tert-butyl-2-methoxy-1,3-dinitro-benzene

5-tert-butyl-2-methoxy-1,3-dinitro-benzene 3 g 4-tert.-butyl-anisol are dissolved in 100 ml acetonitrile, cooled to -30° C. and combined batchwise with 6.1 g nitronium-tetrafluoroborate. The mixture is allowed to come up to -15° C. within one hour, then cooled to -30° C. again, combined with another 1.0 g nitronium tetrafluoroborate and stirred for 30 minutes. It is then divided between saturated aqueous sodium hydrogen carbonate solution and ethyl acetate, the aqueous phase is extracted 3 times with ethyl acetate and the combined organic phases are washed with saturated aqueous sodium chloride solution. After drying with magnesium sulphate the solvents are eliminated in vacuo and the residue is extracted from isopropanol. The precipitated solid is filtered off and dried in vacuo. Yield: 3.75 g (81% of theory) HPLC (method 1): retention time=4.36 min.

References:

US2011/269737,2011,A1 Location in patent:Page/Page column 58