TY - JOUR
T1 - Metal-free synthesis of quinoline-2,4-dicarboxylate derivatives using aryl amines and acetylenedicarboxylates through a pseudo three-component reaction
AU - Ali, Saghir
AU - Khan, Abu T.
N1 - Funding Information:
SA thanks IIT Guwahati for his research fellowship. We also thank the Central Instruments Facility (CIF), IIT Guwahati for instrument facilities. We are thankful to the Department of Science and Technology, New Delhi for financial support (Research Grant No.: CRG/2018/002120/OC) to Professor A. T. Khan. We also thank the MHRD for the 400 MHz NMR facility under the COE-FAST programme (Sanction No. 5-5/ 2014-TS VII) and the DST for providing the 500 MHz NMR facility under the DST-FIST programme (Sanction No. SR/FST/ CS-II/2017/23C). We would like to express our deep sense of gratitude to Professor Bhisma K. Patel for proposing the probable reaction mechanism for the formation of the diester product. We are grateful to Prof S. S. Bag for the discussion on the proposed mechanism. We are also thankful to the referees for their valuable comments as well as the editor for his critical evaluation of our manuscript.
Publisher Copyright:
© 2021 The Royal Society of Chemistry.
PY - 2021/8/28
Y1 - 2021/8/28
N2 - An efficient, useful and one-pot protocol for the synthesis of quinoline-2,4-dicarboxylate scaffolds is accomplished from aryl amines and dimethyl/diethyl acetylenedicarboxylates using 20 mol% molecular iodine as a catalyst in acetonitrile at 80 °C. In addition, the mechanistic explanation for the formation of the desired products is disclosed. The pivotal role of molecular iodine in the formation of the major products, diester quinoline derivatives, and the minor product, triesters, in two cases is described in the mechanism. The notable advantages of this method are non-involvement of a metal catalyst, avoiding of metal contamination in the final product as well as waste generation, use of a low cost and eco-friendly catalyst, ease of handling, high regioselectivity, shorter reaction time, the formation of one C-N and two C-C bonds and a broad substrate scope with good yields.
AB - An efficient, useful and one-pot protocol for the synthesis of quinoline-2,4-dicarboxylate scaffolds is accomplished from aryl amines and dimethyl/diethyl acetylenedicarboxylates using 20 mol% molecular iodine as a catalyst in acetonitrile at 80 °C. In addition, the mechanistic explanation for the formation of the desired products is disclosed. The pivotal role of molecular iodine in the formation of the major products, diester quinoline derivatives, and the minor product, triesters, in two cases is described in the mechanism. The notable advantages of this method are non-involvement of a metal catalyst, avoiding of metal contamination in the final product as well as waste generation, use of a low cost and eco-friendly catalyst, ease of handling, high regioselectivity, shorter reaction time, the formation of one C-N and two C-C bonds and a broad substrate scope with good yields.
UR - http://www.scopus.com/inward/record.url?scp=85113773192&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85113773192&partnerID=8YFLogxK
U2 - 10.1039/d1ob01188j
DO - 10.1039/d1ob01188j
M3 - Article
C2 - 34341812
AN - SCOPUS:85113773192
SN - 1477-0520
VL - 19
SP - 7041
EP - 7050
JO - Organic and Biomolecular Chemistry
JF - Organic and Biomolecular Chemistry
IS - 32
ER -