Transition-metal-catalyzed, directed intermolecular C–Hbond functionalization is synthetically useful but heavily underexplored in multiheteroatom heterocycle synthesis. Herein we report a cobalt catalytic method for the formation of a three-nitrogen-bearing benzotriazine scaffold via the coupling of arylhydrazine and oxadiazolone. This synthetic protocol features a low-cost base metal catalyst, a
A versatile, traceless C–H activation-based approach for the synthesis of diversified heterocycles is reported. Rh(III)-catalyzed, N-amino-directed C–H alkenylation generates either olefination products or indoles (in situ annulation) in an atom- and step-economic manner at room temperature. The remarkable reactivity endowed by this directing group enables scale-up of the reaction to a 10 g scale at
Catalytic Acceptorless Dehydrogenative Coupling of Arylhydrazines and Alcohols for the Synthesis of Arylhydrazones
作者:Feng Li、Chunlou Sun、Nana Wang
DOI:10.1021/jo501161u
日期:2014.9.5
The direct synthesis of arylhydrazones via catalytic acceptorless dehydrogenative coupling of arylhydrazines and alcohols has been accomplished. More importantly, complete selectivity for arylhydrazones and none of the N-alkylated byproducts were generated in this process, which exhibit new potential and provide a new horizon for the development of catalytic acceptorless dehydrogenative coupling reactions
A novel method is presented for the one-pot synthesis of substituted 3-(2-hydroxyethyl)- and 3-(3-hydroxypropyl)indoles (tryptophols and homotryptophols) from aryl hydrazines and silyl-protected ω-(hydroxyoalkyl)alkynes. Various tryptophol derivatives were prepared directly in good yield with excellent regioselectivity via a domino reaction sequence consisting of a titanium-catalyzed hydroamination
A previously elusive RuII‐catalyzed N−N bond‐based traceless C−H functionalization strategy is reported. An N‐amino (i.e., hydrazine) group is used for the directed C−H functionalization with either an alkyne or an alkene, affording an indole derivative or olefination product. The synthesis features a broad substrate scope, superior atom and step economy, as well as mild reaction conditions.