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DOI: 10.1055/s-2005-872255
Iridium-Catalyzed Carbonyl Allylations by Allylic Alcohols with Tin(II) Chloride
Publication History
Publication Date:
29 July 2005 (online)
Abstract
Iridium complex [IrCl(cod)]2 can function as a catalyst for the allylation of aldehydes and ketones by allylic alcohols upon addition of an equimolar amount of SnCl2 in THF-H2O; the reaction is carried out between room temperature and 50 °C to give the corresponding homoallylic alcohols.
Key words
nucleophilic addition - carbonyl allylation - π-allyliridium - tin(II) chloride - allylic alcohols
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Ref. 1.
References
A typical procedure is as follows: To a solution of 1 (0.087 g, 1.5 mmol), benzaldehyde (0.11 g, 1.0 mmol), and SnCl2 (0.28 g, 1.5 mmol) in THF (2 mL) and H2O (0.1 mL) was added [IrCl(cod)]2 (0.013 g, 0.02 mmol), and the solution was stirred at r.t. for 20 h. The solution was diluted with Et2O-CH2Cl2 (2:1; 120 mL), washed with aq 10% HCl solution (20 mL), aq NaHCO3 solution (20 mL), H2O (20 mL), and brine (20 mL). The extracts were dried over anhyd MgSO4. After evaporation of the solvent, column chromatography (silica gel; hexane-EtOAc, 7:1), and then HPLC (Japan Analytical Industry Co. Ltd., LC-908, JAIGEL-2H; CHCl3) afforded 0.13 g (87%) of 1-phenyl-3-buten-1-ol as a colorless oil.
101H NMR (500 MHz): δ = 3.93 (d, J = 6 Hz, 2 H), 5.09 (d, J = 10 Hz, 1 H), 5.23 (d, J = 17 Hz, 1 H), 5.83-5.91 (m, 1 H); 13C NMR (125 MHz): δ = 71.5, 116.0, 136.1.