The transition metal catalyzed C–H bond addition to nitroalkenes has been developed. Very broad nitroalkene scope was observed for this Rh(III)-catalyzed method, including for aliphatic, aromatic and β,β-disubstituted derivatives. Additionally, various directing groups and both aromatic and alkenyl C–H bonds were effective in this transformation. Representative nitroalkane products were converted to dihydroisoquinolones and dihydropyridones in a single step and in high yield by iron mediated reduction and in situ cyclization. Moreover, preliminary success in enantioselective Rh(III)-catalyzed C–H bond addition to nitroalkenes was achieved as was X-ray structural characterization of a nitronate intermediate.

α-Branched amines are present in hundreds of pharmaceutical agents and clinical candidates and are important targets for synthesis. Here we show the convergent synthesis of α-branched amines from three readily accessible starting materials: aromatic C–H bond substrates, terminal alkenes, and aminating agents. This reaction proceeds by an intermolecular formation of C–C and C–N bonds at the sp 3 carbon branch site through an uncommon 1,1-alkene addition pathway. The reaction is carried out under mild conditions and has high functional group compatibility. Ethylene and propylene feedstock chemicals are effective alkene inputs with ethylene in particular providing for the one step synthesis of α-methyl branched amines, a motif prevalent in drug structures. The reaction is scalable, and 1% loading of an air stable dimeric rhodium precatalyst is effective for several different types of products. The use of chiral catalysts also enables the asymmetric synthesis of α-branched amines.

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