反应详情

A mixture of 2,6-dimethylpyrazine (Pyrazine Specialities, Inc., Atlanta, Georgia, containing 2%, 2,5-isomer) (15.5 g) and dimethylamine hydrochloride (13.0 g) was heated until it began refluxing, and then formaldehyde (22.5 g as 38% aqueous solution) was added over a 30-min period. The resulting solution was refluxed for 2 hours. The solution was cooled to room temperature and diluted with water, made basic by the addition of 10% aqueous solution of sodium hydroxide, and extracted with chloroform. After removing the solvent, distillation of the residue gave 7.8 g of 2-methyl-6-dimethylaminoethylpyrazine with 5% of the 2,5-isomer (33% yield), 120°-126° C./12 mm Hg.

1. temperaturewas heated until it
2. temperaturebegan refluxing
3. temperatureThe resulting solution was refluxed for 2 hours
4. extractionextracted with chloroform
5. customAfter removing
6. distillationthe solvent, distillation of the residue