Реакция #158407

Уравнение реакции

(R)-4-((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)-3,5-dimethylbenzonitrile

hydroxylamine hydrochloride

sodium bicarbonate

→

(R,Z)-4-((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)-N′-hydroxy-3,5-dimethylbenzimidamide

Выход 82.0%

Растворители

MeOH

Условия реакции

Обработка

1. 1
   Другоеwas made in a 500 ml flask
2. 2
   Другоеw/3 necks fitted with a reflux condenser) for 10 min
3. 3
   ДругоеNitrogen was bubbled for an additional 10 minutes
4. 4
   ТемператураIt was heated for a total of 25 h
5. 5
   ТемператураThe reaction mixture was cooled
6. 6
   Концентрированиеconcentrated in vacuo
7. 7
   Другоеchromatographed (330 g Redisep cartridge pre-saturated
8. 8
   Промывкаeluted with 10% EtOAc-hexanes)

Методика

Nitrogen was bubbled in a solution of (R)-4-((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)-3,5-dimethylbenzonitrile (8.1 g, 31.0 mmol) and hydroxylamine hydrochloride (4.31 g, 62.0 mmol) in MeOH (150 ml) at room temperature (the solution was made in a 500 ml flask w/3 necks fitted with a reflux condenser) for 10 min. To this was then added the sodium bicarbonate (10.42 g, 124 mmol) in one portion. Nitrogen was bubbled for an additional 10 minutes. The reaction mixture was set to stir at 60° C. It was heated for a total of 25 h. The reaction mixture was cooled, concentrated in vacuo and then chromatographed (330 g Redisep cartridge pre-saturated and then eluted with 10% EtOAc-hexanes). 7.29 g (Yield=82%) of the (R,Z)-4-((2,2-dimethyl-1,3-dioxolan-4-yl)methoxy)-N′-hydroxy-3,5-dimethylbenzimidamide was obtained as a white solid. 1H NMR (400 MHz, CCl3D) δ ppm 7.25 (2H, s), 4.80 (3H, br. s.), 4.49 (1H, qd, J=5.93, 5.71 Hz), 4.18 (1H, dd, J=8.35, 6.59 Hz), 3.94 (1H, dd, J=8.35, 5.93 Hz), 3.81-3.88 (1H, m), 3.73-3.80 (1H, m), 2.29 (6H, s), 1.46 (3H, s), 1.40 (3H, s).

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