反应详情

To a solution of (R)-(−)-tert-butanesulfinamide (3.7 g, 30 mmol) and 4-allyldimethylsilylbenzaldehyde (2 Scheme 1, 6.2 g, 30 mmol) in dry THF (15 mL) was added titanium(IV) propoxide (17 mL, 60 mmol). The mixture was refluxed for 1 h under a N2 atmosphere. The mixture was cooled immediately upon reaction completion, and poured into a brine (30 mL) with rapid stirring. The resulting white suspension was filtered through a pad of celite, which was then washed with ethyl acetate (100 mL). The filtrate was transferred to a separatory funnel where the organic layer was washed with brine (20 mL). The organic layer was dried (Na2SO4), concentrated. The crude oil was purified by column chromatography (1:5 ethyl acetate/hexanes) to afford a colorless oil (6.3 g, 68%); 1H NMR (300 MHz, CDCl3) δ 0.30 (s, 6 H), 1.26 (s, 9 H), 1.76 (d, J=7.92 Hz, 2 H), 4.83 (s, 1 H), 4.88 (d, J=4.41 Hz, 1 H), 5.74 (ddt, J=15.84, 9.27, 8.28 Hz, 1 H), 7.62 (d, J=7.92 Hz, 2 H), 7.82 (d, J=7.92 Hz, 2 H), 8.59 (s, 1 H); 13C NMR (75 MHz, CDCl3) −3.5 (2C), 22.6 (3C), 23.4, 57.8, 113.9, 128.4 (2C),134.0, 134.2 (2C), 134.4, 144.6, 162.8; HRMS (M+1) calcd for C16H26NOSSi 308.1505, found 308.1415.

1. temperatureThe mixture was refluxed for 1 h under a N2 atmosphere
2. temperatureThe mixture was cooled immediately upon reaction completion
3. filtrationThe resulting white suspension was filtered through a pad of celite, which
4. washwas then washed with ethyl acetate (100 mL)
5. customThe filtrate was transferred to a separatory funnel
6. washwhere the organic layer was washed with brine (20 mL)
7. dry with materialThe organic layer was dried (Na2SO4)
8. concentrationconcentrated
9. customThe crude oil was purified by column chromatography (1:5 ethyl acetate/hexanes)