Microwave-Enabled Oxidative Alkoxycyclization of 2'-Aminochalcones by Gold Catalysis.
- 1Synthesis and Enabling Chemical Technologies Laboratory (SECT Lab), Department of Chemistry, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur -603 203, Chengalpattu District, Tamil Nadu, India.
- 2Department of BioMolecular Sciences, School of Pharmaceutical Sciences of Ribeirão Preto (FCFRP), University of São Paulo, Ribeirão Preto, São Paulo14040-903, Brazil.
Abstract
Described herein is a microwave protocol for the synthesis of 4-alkoxyquinolines via oxidative cyclization of 2'-aminochalcones in the presence of alcohols. The reaction employs AuCl3 as a catalyst, with alcohol serving the dual role of both solvent as well as nucleophile. The developed chemistry accommodates linear, branched, cyclic, and terpene-based alcohols affording products in moderate to good yields. The methodology also allowed the one-step preparation of natural alkaloids suh as 4-methoxy-2-phenylquinoline (2a) and graveolinine (2e). Beyond quinolines, our methodology is amenable to the synthetic access of benzofuropyridines. Preliminary mechanistic studies revealed that AuCl3 not only catalyzes the initial aza-cyclization but also triggers the subsequent alcohol addition step. The use of isotopomeric alcohol as nucleophilic partners provides insights on the catalytic C-H bond activation of the products after being formed. Replacing alcohol by toluene halts the reaction at the Michael cyclization step affording dihydroquinolinones with complete product control. Unlike the existing methods, our catalytic approach holds merits such as low solvent quantities, no external oxidants, and no toxic by-products.
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BibTeX
@article{praveen2026microwaveenabled,
title = {{Microwave-Enabled Oxidative Alkoxycyclization of 2'-Aminochalcones by Gold Catalysis.}},
author = {Chandrasekar Praveen and Gabriel de Paula Bueno and Franco Jazon Caires and Giuliano C Clososki},
journal = {The Journal of organic chemistry},
year = {2026},
month = sep,
doi = {10.1021/acs.joc.6c01465},
url = {https://europepmc.org/article/MED/42917433},
note = {CC BY},
}
RIS
TY - JOUR
TI - Microwave-Enabled Oxidative Alkoxycyclization of 2'-Aminochalcones by Gold Catalysis.
AU - Chandrasekar Praveen
AU - Gabriel de Paula Bueno
AU - Franco Jazon Caires
AU - Giuliano C Clososki
PY - 2026
DA - 2026/09/01
JO - The Journal of organic chemistry
DO - 10.1021/acs.joc.6c01465
UR - https://europepmc.org/article/MED/42917433
AB - Described herein is a microwave protocol for the synthesis of 4-alkoxyquinolines via oxidative cyclization of 2'-aminochalcones in the presence of alcohols. The reaction employs AuCl3 as a catalyst, with alcohol serving the dual role of both solvent as well as nucleophile. The developed chemistry accommodates linear, branched, cyclic, and terpene-based alcohols affording products in moderate to good yields. The methodology also allowed the one-step preparation of natural alkaloids suh as 4-methoxy-2-phenylquinoline (2a) and graveolinine (2e). Beyond quinolines, our methodology is amenable to the synthetic access of benzofuropyridines. Preliminary mechanistic studies revealed that AuCl3 not only catalyzes the initial aza-cyclization but also triggers the subsequent alcohol addition step. The use of isotopomeric alcohol as nucleophilic partners provides insights on the catalytic C-H bond activation of the products after being formed. Replacing alcohol by toluene halts the reaction at the Michael cyclization step affording dihydroquinolinones with complete product control. Unlike the existing methods, our catalytic approach holds merits such as low solvent quantities, no external oxidants, and no toxic by-products.
SN - 0022-3263
SN - 1520-6904
ER -