The study of the reaction mechanism and complex network for heterogeneously catalyzed tandem reactions is challenging but can guide reaction design and optimization. Here, we describe a case study using bifunctional metal–organic framework supported Pd nanoparticles (Pd/UiO-66(HCl)) for the one-pot tandem synthesis of substituted tetrahydroquinolines via the Claisen–Schmidt condensation and reductive intramolecular cyclization. The directly observed evolution of intermediates and products, including reactive species containing hydroxylamine group and unstable intermediate 2-phenyl-3,4-dihydroquinoline, was enabled by operando magic angle spinning nuclear magnetic resonance studies under 50 bar H2. The reaction network of the tandem reaction is deduced based on reaction kinetic information obtained from the operando study. The optimized procedure was applied to various acetophenone and nitrobenzaldehyde derivatives carrying different functional groups, and eight valuable substituted tetrahydroquinolines were obtained in moderate to good yields. This work provides a molecular-level understanding of the catalytic system and brings up new opportunities for efficient and sustainable synthesis of medicinally relevant building blocks.
Chen, Jingwen, et al. "Tandem synthesis of tetrahydroquinolines and identification of the reaction network by <em>operando</em> NMR." Catalysis Science and Technology, vol. 11, no. 13, Apr. 2021. https://doi.org/10.1039/d1cy00418b
Chen, Jingwen, Qi, Long, Zhang, Biying, et al., "Tandem synthesis of tetrahydroquinolines and identification of the reaction network by <em>operando</em> NMR," Catalysis Science and Technology 11, no. 13 (2021), https://doi.org/10.1039/d1cy00418b
@article{osti_1798969,
author = {Chen, Jingwen and Qi, Long and Zhang, Biying and Chen, Minda and Kobayashi, Takeshi and Bao, Zongbi and Yang, Qiwei and Ren, Qilong and Huang, Wenyu and Zhang, Zhiguo},
title = {Tandem synthesis of tetrahydroquinolines and identification of the reaction network by <em>operando</em> NMR},
annote = {The study of the reaction mechanism and complex network for heterogeneously catalyzed tandem reactions is challenging but can guide reaction design and optimization. Here, we describe a case study using bifunctional metal–organic framework supported Pd nanoparticles (Pd/UiO-66(HCl)) for the one-pot tandem synthesis of substituted tetrahydroquinolines via the Claisen–Schmidt condensation and reductive intramolecular cyclization. The directly observed evolution of intermediates and products, including reactive species containing hydroxylamine group and unstable intermediate 2-phenyl-3,4-dihydroquinoline, was enabled by operando magic angle spinning nuclear magnetic resonance studies under 50 bar H2. The reaction network of the tandem reaction is deduced based on reaction kinetic information obtained from the operando study. The optimized procedure was applied to various acetophenone and nitrobenzaldehyde derivatives carrying different functional groups, and eight valuable substituted tetrahydroquinolines were obtained in moderate to good yields. This work provides a molecular-level understanding of the catalytic system and brings up new opportunities for efficient and sustainable synthesis of medicinally relevant building blocks.},
doi = {10.1039/d1cy00418b},
url = {https://www.osti.gov/biblio/1798969},
journal = {Catalysis Science and Technology},
issn = {ISSN 2044-4753},
number = {13},
volume = {11},
place = {United States},
publisher = {Royal Society of Chemistry},
year = {2021},
month = {04}}
USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division; National Key R&D Program of China; National Natural Science Foundation of China (NSFC); Zhejiang University
Grant/Contract Number:
AC02-07CH11358
OSTI ID:
1798969
Alternate ID(s):
OSTI ID: 1782757
Report Number(s):
IS-J--10,504
Journal Information:
Catalysis Science and Technology, Journal Name: Catalysis Science and Technology Journal Issue: 13 Vol. 11; ISSN 2044-4753