Aldehyde as a Traceless Directing Group for Rh(III)-Catalyzed C–H Activation: A Facile Access to Diverse Indolo[1,2-a]quinolines
摘要:
The aldehyde group has been developed for the first time as a traceless directing group to promote regioselective Rh(III)-catalyzed C-H activation/cyclization of indolyl aldehydes with alkynes. This protocol streamlines access to a variety of appealing indolo[1,2-a]quinoline structures. As illustrative examples, a concise three-step synthesis of indolo[1,2-a]quinoline-based sensitizers is accomplished that exhibits the potential of C-H activation in the construction of organic optoelectronic materials.
palladium-catalyzed oxidative coupling reactions of N-substituted indoles or their carboxylic acid derivatives with alkynes. Unsymmetrically octasubstituted carbazoles can also be obtained by the stepwise couplings of 1-methylpyrrole-2-carboxylic acid with two different alkynes. In addition, the present coupling procedure is applicable to the synthesis of other various heteroarenes possessing di-, tri-, and tetracyclic
Nickel-Catalyzed Cyclization Strategy for the Synthesis of Pyrroloquinolines, Indoloquinolines, and Indoloisoquinolines
作者:Sampath Thavaselvan、Kanniyappan Parthasarathy
DOI:10.1021/acs.orglett.0c01055
日期:2020.5.15
An inexpensive and benchtop stable Ni-catalyst/Zn system for the synthesis of pyrrolo/indoloquinolines and indolo[2,1-a]isoquinolines is explored. This platform provides a one-pot entry for the preparation of various pyrrolo and indoloquinolines/isoquinolines, which involves successive C-C and C-N bond formation, respectively. In addition, we have also performed the preliminary photophysical studies