反应详情

A mixture of 3-methoxybenzaldehyde (10.0 g, 73.4 mmol), 1,4-dioxa-8-azaspiro[4.5]decane (21.0 g, 146.9 mmol), sodium triacetoxyborohydride (31.1 g, 146.9 mmol), and acetic acid (4.4 mL, 73.45 mmol) in 1,2-dichloroethane (100 mL), was stirred at ambient temperature. After 19 h, a 2 N aqueous sodium carbonate solution (220 mL) was added portionwise. After stirring for 15 min, the aqueous layer was separated and extracted with methylene chloride (200 mL). The combined organic layers were washed with brine (100 mL), dried over anhydrous sodium sulfate and concentrated in vacuo to provide 8-(3-methoxybenzyl)-1,4-dioxa-8-azaspiro[4.5]decane (16.0 g, 82%) as a yellow oil: 1H NMR (CDCl3, 400 MHz) δ 7.27-7.20 (m, 1H), 6.93-6.88 (m, 2H), 6.79 (dd, J=2.4, 8.2 Hz, 1H), 3.94 (s, 4H), 3.82-3.78 (m, 3H), 3.50 (s, 2H), 2.56-2.47 (m, 4H), 1.74 (t, J=5.6 Hz, 4H); ESI MS (m/z) 264 [M+H].

1. stirringAfter stirring for 15 min
2. customthe aqueous layer was separated
3. extractionextracted with methylene chloride (200 mL)
4. washThe combined organic layers were washed with brine (100 mL)
5. dry with materialdried over anhydrous sodium sulfate
6. concentrationconcentrated in vacuo