Reaction #2161244

Reaction equation

Benzaldehyde

isopropyl magnesium chloride

tributyl tin hydride

→

Bu3SnCH(OH)Ph

Yield 28.9%

Solvents

diethyl ether

diethyl ether

Conditions

Workup

1. 1
   OtherThe resulting reaction mixture
2. 2
   Temperaturewas heated
3. 3
   Temperatureto reflux
4. 4
   Temperaturewhile maintaining the temperature at about 0° C
5. 5
   OtherThe resulting reaction mixture
6. 6
   Temperaturewas then heated
7. 7
   Temperatureto reflux
8. 8
   workup.STIRRINGstirred for 1 h
9. 9
   Temperaturebefore cooling back down to room temperature
10. 10
    OtherThe reaction was then quenched by addition of approximately 15 mL aqueous ammonium chloride under nitrogen
11. 11
    FiltrationThe resulting mixture was filtered through a glass frit
12. 12
    Extractionthe solids were extracted with diethyl ether
13. 13
    ConcentrationThe combined organic extracts were concentrated under vacuum
14. 14
    Filtrationfiltered through Florisil™
15. 15
    WashThe Florisil™ pad was washed further with hexane
16. 16
    ConcentrationThe combined organic extracts were concentrated under vacuum
17. 17
    Otherto afford an oil

Procedure

This example demonstrates the synthesis and purification of the alpha-hydroxystannane complex Bu3SnCH(OH)Ph. Under nitrogen, a dry 250 mL round bottom flask was charged with 2.0 M isopropyl magnesium chloride in diethyl ether (20.6 mL, 41.2 mmol). An additional 15 mL of diethyl ether was then added. To this stirred solution was added tributyl tin hydride (10.0 g, 34.4 mmol) dropwise over a period of 10-15 min. The resulting reaction mixture was heated to reflux, stirred for 1 h, and then cooled down to about 0° C. Benzaldehyde (4.0 g, 37.8 mmol) was then added dropwise over a period of approximately 10 min while maintaining the temperature at about 0° C. The resulting reaction mixture was then heated to reflux and stirred for 1 h before cooling back down to room temperature. The reaction was then quenched by addition of approximately 15 mL aqueous ammonium chloride under nitrogen. The resulting mixture was filtered through a glass frit and the solids were extracted with diethyl ether. The combined organic extracts were concentrated under vacuum and filtered through Florisil™. The Florisil™ pad was washed further with hexane. The combined organic extracts were concentrated under vacuum to afford an oil. Chromatography on silica gel using 95/5 hexane/ethyl acetate as the eluent afforded 3.95 g of Bu3SnCH(OH)Ph as a pale yellow oil. 1H NMR (CDCl3) δ 7.2 (t, 2H, Hmeta), 7.1d (d, 1 2H, Hortho), 7.0 (t, 1H, Hpara), 5.1 [d, 1H, CH(OH)], 1.7 [d, 1H, CH(OH)], 1.4-0.7 (m, 27H, Bu's); 119Sn NMR (CDCl3) δ −25.0 relative to SnMe4; 13C NMR (CDCl3) δ 147.8 (Cipso), 128.4 (Cortho or Cmeta), 124.6 (Cpara), 122.9 Cortho or Cmeta), 71.3 [CH(OH)], 28.9 and 27.4 (CH2's), 13.6 (CH3), 9.1 (CH2).

Source