Synthesis of 1<i>H</i>-Indazoles from Imidates and Nitrosobenzenes via Synergistic Rhodium/Copper Catalysis
作者:Qiang Wang、Xingwei Li
DOI:10.1021/acs.orglett.6b00727
日期:2016.5.6
Nitrosobenzenes have been used as a convenient aminating reagent for the efficient synthesis of 1H-indazoles via rhodium and copper catalyzed C–H activation and C–N/N–N coupling. The reaction occurred under redox-neutral conditions with high efficiency and functional group tolerance. Moreover, a rhodacyclic imidate complex has been identified as a key intermediate.
and expeditious protocol for the synthesis of diverse difunctionalized indenones through rhodium-catalyzed C–H activation and multistep cascade reaction of benzimidates and alkenes has been developed. The transformation involves the cleavage and formation of multiple bonds in one pot under mild reaction conditions, and Mn(OAc)2 plays an important role in the reaction.
and expeditious protocol for the synthesis of difunctionalized indenes from readily available benzimidates and nitroalkenes through rhodium‐catalyzed C−H activation and cyclization is reported here. The transformation exhibits powerful reactivity, tolerates a large number of functionalgroups, and proceeds in moderate to high yields under an ambient atmosphere, providing a straightforward method to access
Synthesis of naphthalene-substituted aromatic esters <i>via</i> Rh(<scp>iii</scp>)-catalyzed C–H bond naphthylation and cascade directing group transformation
A regioselective Rh(III)-catalyzed C–H bond naphthylation and cascade directing group (DG) transformation has been realized with aryl imidates and oxa bicyclic alkenes. Diverse naphthalene-substituted aromatic esters were synthesized fruitfully. The DG transformation into ester endows the strategy with chances of further C–H bond functionalization and derivatization. Preliminary mechanistic studies
Herein, we report a cobalt-catalyzed hydroarylation of maleimides followed by an annulation sequence for the synthesis of polycyclic azaheterocycles in one pot. The reaction proceeds under redox-neutral conditions and is compatible with various functional groups. Notably, the as-prepared product exhibits potential photophysical properties.