[C:1]1([CH:7]=[N+]=[N-])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[H][H].[CH:12](=[O:19])[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1>ClCCl.C([O-])(=O)C.[Rh+2].C([O-])(=O)C>[C:1]1([CH:7]2[O:19][CH:12]2[C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1Phenyl diazomethane (1 mmol in 6 ml of t-butylmethylether) was added to a stirred solution of a sulphide of formula (B) wherein R' is hydrogen (0.2 mmol), rhodium (II) acetate (4.0 mg, 0.01 mmol) and benzaldehyde (1 mmol) in dichloromethane (4 ml) at room temperature over a period of 24 hours. After the addition was complete the solvent was removed in vacuo and the residue was chromatographed over silica [eluent dichloromethane:petrol (2:3)] to give the titled compound in 58% yield and 11% ee.
Wird geladen…
