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The ubiquitous nature of C-H bonds in organic molecules makes them attractive as a target for rapid complexity generation, but brings with it the problem of achieving selective reactions. In developing new methodology for C-H functionalization, alkenes are an attractive starting material due to their abundance and low cost. Here we describe the conversion of 1-alkenes into 1,4-diols. The method involves the installation of a Si,N-type chelating auxiliary group on the alkene followed by iridium catalyzed C-H silylation of an unactivated δ-C(sp3)-H bond to produce an silolane intermediate. Oxidation of the C-Si bonds affords a 1,4-diol. The method is demonstrated to have broad scope and a good functional group compatibility by application to the selective 1,4-oxygenation of several natural products and derivatives.

Two methods for remote aromatic C–H oxygenation reaction have been developed. Method 1, the Cu-catalyzed oxygenation reaction is highly efficient for cyclization of electron-neutral and electron-rich biaryl carboxylic acids into 3,4-benzocoumarins. Method 2, the K2S2O8-mediated oxygenation reaction, is more general and practical for cyclization of substrates with electron- donating and -withdrawing groups (see scheme).