6-Quinoxalinecarboxylic acid, 1,2-diMethylhydrazide synthesis

Yield:937279-41-9 47%

Reaction Conditions:

with N-ethyl-N,N-diisopropylamine in dichloromethane at -78;

Steps:

7.B

Step 7B: Quinoxaline-6-carboxylic acid N,N'-dimethyl-hydrazideIn a 25 mL round bottom flask, 1,2-dimethylhydrazine (690 mg, 5.2 mmol) was added with CH₂Cl₂ (5 mL). DIEA (2 mL, 10.4 mmol) was then added and the mixture was cooled to -78° C. Quinoxaline-6-carbonyl chloride (500 mg, 2.6 mmol) was then added very slowly dropwise as a suspension in CH₂Cl₂ (5 mL). The mixture was diluted with 10 mL of CH₂Cl₂ (5 mL), extracted with water (20 mL), dried with NaSO₄, and rotovapped to dryness and dried on the vacuum line to yield 260 mg of Quinoxaline-6-carboxylic acid N,N'-dimethyl-hydrazide (47%).¹H NMR 300 MHz (CDCl₃) δ 2.65 (s, 3H), 3.00 (s, 3H), 7.91 (m, 1H), 8.31 (m, 2H), 8.78 (m, 2H).(M/Z+1) 217.15.

References:

US2010/56505,2010,A1 Location in patent:Page/Page column 30