To a 500 mL round bottom flask equipped with stir bar was added 5-bromo-2-furanoic acid (6.69 g, 35 mmol, 1 equiv) and dichloromethane (120 mL, ≈ 0.3M). To this stirred heterogenous¹ solution was added 1,1’-carbonyl diimadazole (6.24 g, 38.5 mmol, 1.1 equiv.) in one portion, turning the solution from milky white to a clear yellow and resulting in the evolution of CO₂ gas.² The now yellow solution was allowed to stir for 45 minutes. At this time, N-O-dimethylhydroxylamine hydrochloride (3.76 g, 38.5 mmol, 1.1 equiv) was added all at once turning the solution a cloudy white. The reaction mixture was stirred for six hours. The reaction mixture was then quenched with 50 mL of 1 M HCl³ and stirred vigorously for 10 minutes. After this time, the solution was transferred to a separatory funnel and the layers were separated. The aqueous layer was extracted with DCM (2 X 100 mL). The combine organic layers were washed with 1 M HCl (100 mL), deionized water (100 mL) and a 1:1 mixture of brine and a saturated sodium bicarbonate solution (200 mL). The organic layer was dried with Na₂SO₄ and the solvent was removed in vacuo by rotary evaporation  to afford the pure amide, 5-bromo-N-methoxy-N-methylfuran-2-carboxamide (5.70 g, 70%).

We've found this reaction to be an excellent alternative to synthesizing Weinreb amides. It is very useful in systems where synthesis of the acid chloride from the carboxylic acid is complicated by sensitive moieties (i.e. alkenes etc).

Notes:
1. As long as the acid has some solubility in DCM, the reaction with CDI will proceed quite readily. If no reaction is observed (i.e. if the reaction does not become homogeneous) THF can be added as a co-solvent. 
2. While gas is evolved, minimal to no heat is given off and hence cooling is not required
3. In the case of acid-sensitive or basic species, alternative workup conditions are as follows: After reaction completion, quench with an equal volume a 1 M NaOH solution relative to the solvent. Extract the aqueous layer with DCM (twice with  a volume equal to the initial solvent volume), wash with brine (once with a volume equal to the initial solvent volume ), dry with Na_2­SO₄ and remove the solvent in vacuo via rotary evaporation

¹H NMR (CDCl₃, 400 MHz) δ ppm 3.17 (s, 3 H) 3.62 (s, 3 H) 6.32 (d, J=3.42 Hz, 1 H) 6.94 (d, J=3.67 Hz, 1 H)
¹³C NMR (CDCl₃, 100 MHz) δ ppm 32.98 (CH₃) 61.34 (CH₃) 113.54 (CH) 119.64 (CH) 126.31 (C) 147.57 (C) 157.75 (C)
GC-MS (EI) 235 ([M]⁺, ⁸¹Br  7%), 233([M]⁺, ⁷⁹Br  7%), 175 (⁸¹Br  98%), 173 (⁷⁹Br  100%), 119 (⁸¹Br 24%), 117 (⁷⁹Br  24%) 66 (16%) 38 (19%).