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.
Keywords: C-H functionalization; Rh(III) catalysis; dihydroisoquinolone; enantioselective catalysis; nitroalkene.