Article
Chemistry, Multidisciplinary
Mengyuan Chen, Yuchen Liang, Taotao Dong, Weijian Liang, Yanping Liu, Yage Zhang, Xin Huang, Lichun Kong, Zhi-Xiang Wang, Bo Peng
Summary: The study merged the Morita-Baylis-Hillman (MBH) reaction and the [3,3]-sigmatropic rearrangement to achieve the [3,3]-rearrangement of aryl sulfoxides with alpha,beta-unsaturated nitriles, offering a new approach to prepare alpha-aryl alpha,beta-unsaturated nitriles with Z-selectivity. Control experiments and DFT calculations support a four-stage reaction sequence, including assembly, Lewis base addition, rearrangement, and E1cB-elimination, explaining the remarkable Z-selectivity of the reaction.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Samar Bou Zeid, Samar Eid, Fadia Najjar, Aurelie Mace, Ivan Rivilla, Fernando P. Cossio, Vincent Dorcet, Thierry Roisnel, Francois Carreaux
Summary: The effect of microwave irradiation on the 1,3-Dioxa-[3,3]-sigmatropic rearrangement of aryl allylic carbamates was investigated, showing faster reaction acceleration and similar or improved yields compared to conventional heating conditions. This experimental improvement extended the diversity of carbamates able to undergo this rearrangement, and a synthetic pathway to access new heterocyclic structures was successfully developed. DFT and Fragment Distortion studies demonstrated polar transition structures with lower activation barriers.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Souvik Guha, Satyanarayana Gadde, Naresh Kumar, David StClair Black, Subhabrata Sen
Summary: A series of telescoping methodologies were reported for the one-pot synthesis of biologically relevant β-carboline derivatives 6 and spiro[pyrrolidinone-3,3']indole 7. Careful optimization of the reaction sequence and conditions allowed for the exclusive access to compounds 6 and 7. Air oxidation of gamma-carbolinones 6 yielded aromatic gamma-carbolines 8.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Bin Sun, Xiaohui Zhuang, Jieli Yin, Kesheng Zhang, Haiyun Zhao, Can Jin
Summary: In this study, a photoredox-catalyzed radical cascade reaction was developed for the efficient synthesis of 4-hydroxyalkyl-3,3-difluoro-gamma-lactams. The reaction demonstrated good tolerance towards various functional groups, required lower photocatalyst loading, and was easy to perform.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Wei Liu, Le Zhang, Ye Liu, Shi-Lu Fan, Jian-Jun Dai, Wei Tao, Hui-Xia Zhu, Hua Xiao
Summary: In this study, a consecutive S(N)2'/S(N)2'' addition of phenol to gamma-vinyl MBH carbonate was performed, leading to the formation of functionalized exocyclohexenes with excellent chemoselectivity. Additionally, using o-hydroxychalcones as pronucleophiles, a series of pharmaceutically intriguing tricyclic chromane derivatives were selectively synthesized through an S(N)2'/S(N)2''/intramolecular Diels-Alder reaction sequence with good diastereoselectivity.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Mikhail K. Klychnikov, Radek Pohl, Ivana Cisarova, Ullrich Jahn
Summary: A two-step radical-based approach is reported for the synthesis of gamma-lactams bearing three to four stereocenters from epoxides, N-allylic silylacetamides, and TEMPO. The method offers good yields and selectivity, showcasing a rare oxidative geminal C-C/C-O difunctionalization next to carbonyl groups. Functionalized pyrrolidones can be easily diversified from the resulting products, which converge to 3,4-trans-gamma-lactams by base-mediated equilibration. Stereochemical models for both reaction types have been developed.
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Review
Chemistry, Multidisciplinary
M. S. Kobzev, A. A. Titov, A. V. Varlamov
Summary: This review summarizes the synthesis of heterocyclic compounds using [3,3]-sigmatropic transformations, covering reactions such as the Fischer, Claisen, and Cope rearrangements. These methods are shown to be efficient for synthesizing complex heterocyclic systems with multiple chiral centers, and can be used in the construction of medium size heterocycles containing oxygen, nitrogen, and sulfur, as well as in the synthesis of condensed systems and natural compounds.
RUSSIAN CHEMICAL BULLETIN
(2021)
