[Br:1][C:2]1[CH:3]=[CH:4][C:5]([CH3:11])=[C:6]([CH:10]=1)[C:7](O)=[O:8].[CH:12]([N:15](CC)C(C)C)(C)C.CN.O1CCCC1.CCCP1(OP(CCC)(=O)OP(CCC)(=O)O1)=O.C(OCC)(=O)C>ClCCl>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([CH3:11])=[C:6]([CH:10]=1)[C:7]([NH:15][CH3:12])=[O:8]To a solution of 5-bromo-2-methylbenzoic acid (2.325 mmol, 0.5 g) in dichloromethane (25 mL) under nitrogen was added N,N-diisopropylethylamine (0.75 g, 5.8 mmol). Reaction then cooled in an ice bath to 2° C. and the yellow solution treated with 2M methylamine in tetrahydrofuran (3.49 mL, 6.98 mmol) over 5 minutes, followed by 1-propanephosphonic acid cyclic anhydride as a 50% wt solution in ethyl acetate (2.08 mL, 3.49 mmol) added dropwise. The ice bath was then removed and stirring continued overnight. The mixture was purified on silica (15 g column on Isolera 4) eluting with 0-5% methanol in dichloromethane to afford 5-Bromo-N,2-dimethylbenzamide (0.5 g, 2.2 mmol).
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