An efficient and practical protocol for the geminal heterodihalogenation of methyl ketones by using readily available dimethyl sulfoxide and a combination of HCl and HBr is reported. Control experiments suggested that the acidity of the solution, as well as the oxidizing ability and nucleophilicity of the dimethyl sulfoxide might work cooperatively in ensuring the success of the tandem substitution. Its operational simplicity, easy accessibility, and mild oxidative conditions suggest that the present strategy might be useful for the assembly of bromochloromethyl functional groups in drug discovery.
One-pot synthesis of unsymmetrical benzils from aryl methyl ketones and arenes in the presence of selenous acid catalysed by p-toluenesulfonic acid monohydrate