反应详情

(EX-1A) A solution of ethyl benzimidate hydrochloride (92.25 g, 496.9 mmol) in 300.0 mL dry methanol (1.68 M) was cooled to ca 0° C. and added a solution of aminoacetaldehyde dimethyl acetal (73.10 mL, 670.9 mmol) in dry methanol (75.0 mL, 9.0 M) drop wise at such a rate the temperature was kept below 5° C. The resulting solution was allowed to stir for 3 days with the temperature being maintained below 5° C. The reaction mixture was then concentrated under reduced pressure to give a yellow oil. The residue was dissolved in 1 N NaOH (750 mL) and extracted with dichloromethane (4×250 mL). The organic solutions were combined, dried (MgSO4), and concentrated to give 108.13 g crude N-(2,2-dimethoxyethyl)benzamidine as a yellow oil.

1. customwas kept below 5° C
2. temperaturebeing maintained below 5° C
3. concentrationThe reaction mixture was then concentrated under reduced pressure
4. customto give a yellow oil
5. extractionextracted with dichloromethane (4×250 mL)
6. dry with materialdried (MgSO4)
7. concentrationconcentrated