Dichloromethane → HCID 131732777, compound

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Reaction Conditions

Reaction Steps

A solution of the commercially available (S,S) dioxaborolane ligand (7.37 g, 27.3 mmol) in DCM (20 mL) was added. The mixture was stirred for 10 minutes. The precipitate dissolves yielding a clear solution. A solution of the alkene from step B of this example (8.53 g, 22.7 mmol) in DCM (20 mL) was added. The solution was warmed to 0° C. and stirred for 24 hours. The solution remains clear after stirring for 24 hours. The reaction was quenched after 24 hr by addition of 50 ml of sat'd aq. NH4Cl. The mixture was placed in a separatory funnel, 250 ml DCM and 200 ml 10% HCl (aq) added, shaken, and the layers separated. The aqueous layer was re-extracted with DCM (2×150 ml), the organic layers combined, transferred to a Morton flask. 2N NaOH (300 ml) and 50 ml of 30% H2O2 were added. The biphasic solution was stirred vigorously for 12 hours. The layers were separated and the aqueous phase was re-extracted with DCM (2×150 ml), the organic phases were combined, washed with 10% HCl (aq, 250 ml), 1N Na2S2O3 (250 ml), sat'd NaHCO3 (250 ml), brine (250 ml), dried over MgSO4, filtered and stripped. The material was purified by chromatography on SiO2 eluting with 30% EtOAc:Hexanes. The desired product is obtained as a mixture with the minor diastereomer and the residual SM. The desired diastereomer was isolated by Chiralpak IA stationary phase chromatography.

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