α-Halo carbonyls enable meta selective primary, secondary and tertiary C–H alkylations by ruthenium catalysis
作者:Andrew J. Paterson、Callum J. Heron、Claire L. McMullin、Mary F. Mahon、Neil J. Press、Christopher G. Frost
DOI:10.1039/c7ob01192j
日期:——
selective C–H alkylation of arenes is described using a wide range of α-halo carbonyls as coupling partners. Previously unreported primary alkylations with high meta selectivity have been enabled by this methodology whereas using straight chain alkyl halides affords ortho substituted products. Mechanistic analysis reveals an activation pathway whereby cyclometalation with a ruthenium(II) complex activates
para-Selective hydroxylation of alkylarylethers is established, which proceeds with a ruthenium(II) catalyst, hypervalent iodine(III) and trifluoroacetic anhydride via a radical mechanism. This protocol tolerates a wide scope of substrates and provides a facile and efficient method for preparing clinical drugs monobenzone and pramocaine on a gram scale.