Article
Chemistry, Organic
Undamatla Suri Babu, Maneesh Kumar Reddy Singam, Muniganti Naveen Kumar, Jagadeesh Babu Nanubolu, Maddi Sridhar Reddy
Summary: This article presents a general approach to the synthesis of napthyridinones through the Pd-catalyzed annulation of 1,6-enynes with 2-iodoanilines. The protocol involves a rare carbo-aminative cyclization via the 6-endo-trig mode, and overcomes the commonly observed exo-trig/dig cyclizations. The regioselective aryl palladation of alkyne followed by intramolecular Heck-type reaction enables the cascade synthesis.
Article
Chemistry, Physical
Qianqian Lu, Jun Gu, Fang Liu, Chunsen Li
Summary: In this study, density functional theory calculations were used to investigate the influence of tethered unsaturated carbon-carbon bond on the cycloisomerization mechanisms in rhodium(I)-catalyzed reactions of 1,6-allenynes. The results showed that distinct regioselectivity between alkene and alkyne insertions and the contrasting reactivity of rhodium-alkyl and rhodium-alkenyl intermediates contribute to the divergent cycloisomerization mechanisms. Further analysis revealed the effects of alkyne substituent and carbon chain length of the reactant on product selectivity.
Article
Chemistry, Organic
Zhantao Yang, Zhiqiang Yu, Yulin He, Wei Feng, Yinchao Zhang, Junjie Wang, Xiangtao Kong, Chun-Hua Yang
Summary: A Rh-catalyzed regioselective, stereoselective carbocyclization/borylation reaction of acrylate-containing 1,6-enynes was developed, enabling the synthesis of versatile and densely functionalized pyrrolidine compounds. The reaction allows for the formation of pyrrolidines with either (Z) or uncommon (E) geometry at the double bond, depending on the substituent on the alkyne, with sterically hindered and conjugative aryl groups favoring the latter configuration. The reaction also leads to the formation of a tetrasubstituted vinyl boronate, containing an all-carbon quaternary stereocenter.
Article
Chemistry, Organic
Xia Chen, Zengwei Luo, Yong Chen, Yonghui Zhang
Summary: A simple and efficient catalytic reaction for the synthesis of valuable functionalized compounds has been developed. The reaction proceeds in one step under environmentally friendly conditions and has shown excellent yields. The study also revealed the involvement of an unconventional intermediate in the reaction mechanism.
Article
Chemistry, Multidisciplinary
Qishun Liu, Yufen Lv, Ruisheng Liu, Xiaohui Zhao, Jiawen Wang, Wei Wei
Summary: A convenient and regioselective sulfonylation/cyclization method has been developed for the synthesis of sulfonylated gamma-butyrolactams. The reaction can be efficiently conducted under catalyst- and additive-free conditions, selectively constructing C-S and C-C bonds in one-pot procedure.
CHINESE CHEMICAL LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Zhi Chen, Yu-Fan Li, Shun-Zhong Tan, Qin Ouyang, Zhi-Chao Chen, Wei Du, Ying-Chun Chen
Summary: Herein, a palladium-catalysed multiple auto-tandem reaction for the efficient synthesis of formal pyrrolylmethylated amine products was reported. The regiodivergent selectivity could be switched by tuning the catalytic conditions. In addition, remote chirality transfer was achieved using an achiral ligand.
Article
Chemistry, Organic
Jiaao Ge, Hongli Wu, Deping Kong, Genping Huang
Summary: Density functional theory calculations were used to investigate the cobalt-catalyzed intermolecular hydroacylation/cyclization of 1,6-enynes with aldehydes. The study showed that the initial oxidative cyclization is the rate-determining step of the overall reaction, and the enantioselectivity is mainly caused by steric repulsion between the aldehyde moiety and the aryl substituent of the 1,6-enyne.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Organic
Fei Hou, Yingtang Ning, Lili Song, Zequn Tan, Jiawen Yang, Zhigang Liu, Fen-Er Chen
Summary: A rhodium-catalyzed enantioselective hydroboration/cyclization reaction of 1,6-enynes using a spirosiladiphosphine ligand has been achieved. The reaction allows the synthesis of five-membered hetero- and carbocycles bearing a boron handle with high activity and selectivity. Various enynes and organoboranes have been successfully utilized, including enynes containing terminal alkynes for the first time. The high yields and selectivities highlight the synthetic utility of these novel spirosiladiphosphine ligands.
Article
Chemistry, Organic
Ming Dong, Danfeng Wang, Xiaofeng Tong
Summary: The dihalogenative cyclization of 1,6-enyne with the assistance of PhI(OAc)(2) and lithium halide follows a plausible radical mechanism, with the resulting pyrrolidine products containing alkyl- and alkenyl-halide groups that are demonstrated to be suitable for further transformations.
Article
Chemistry, Organic
Xinyi Ren, Lin Tang, Chaoren Shen, Huimin Li, Peng Wang, Kaiwu Dong
Summary: A palladium-catalyzed asymmetric hydroesterification-cyclization method was developed for efficient preparation of enantioenriched gamma-lactams, with good selectivities and a broad substrate scope. The correlation between multiple selectivities and N-substitutes of the amide linker in the substrate was demonstrated through crystallographic evidence and control experiments.
Article
Chemistry, Organic
Andrea Serafino, Nicola Camedda, Matteo Lanzi, Nicola Della Ca, Gianpiero Cera, Giovanni Maestri
Summary: Trinuclear all-metal aromatic palladium clusters catalyze C-C forming reactions of polyunsaturated substrates, resulting in the synthesis of two new families of tricyclic compounds. The method exhibits peculiar regio- and diastereoselectivity, demonstrating the complementarity of trinuclear palladium complexes to their mononuclear peers. Preliminary studies on the mechanism of these polycyclization reactions revealed unique features of the homogeneous catalytic system.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Anandarao Munakala, Rambabu Chegondi
Summary: A highly regioselective silver(I)-catalyzed intramolecular annulation method was reported in this study, which enables the synthesis of meta-substituted phenols with enone functionality from alkyne-tethered cyclohexadienones. The reaction proceeds through intramolecular 1,6-enyne cyclization, aromatization, and oxetene ring rearrangement, and is compatible with a wide range of C-tethered cyclohexadienones to afford indanes in high yields. The unique functionality of the products allows for further transformations to expand diversity.
Article
Chemistry, Multidisciplinary
Hui-Lin Li, Wei-Sheng Huang, Fang-Ying Ling, Li Li, Jun-Hao Yan, Hao Xu, Li-Wen Xu
Summary: Organosilicon compounds are important reagents and intermediates in the construction of new materials and complex products. In this study, a highly diastereoselective rhodium-catalyzed cycloisomerization reaction was demonstrated using (EtO)3SiH to accelerate the cyclization reaction and yield spiro-fused succinimide and pyrazolone derivatives as a single diastereoisomer. The proposed mechanism involves an active Rh-H species from the hydrosilane as the H-donor in the spiro-type cycloisomerization reaction.
CHEMISTRY-AN ASIAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Katsumasa Tanaka, Hiroshi Hattori, Ryota Yabe, Takahiro Nishimura
Summary: In this study, an iridium-catalyzed sp(3) C-H alkylation reaction was conducted to achieve high yields in the reaction between N-methyl groups and 1,5- and 1,6-dienes, resulting in the formation of five- and six-membered carbocyclic compounds. The use of a chiral bidentate phosphine ligand allowed for the asymmetric synthesis of cyclic compounds.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Tao Wang, Ji-Xun Guan, Yun-Xuan Tan, Ping Tian
Summary: This paper reports the first cobalt-catalyzed highly selective arylation carbocyclization reaction of 1,6-allenynes with arylboronic acids. The reaction demonstrates moderate to high yields, broad substrate scope, and good compatibility with functional groups.
Article
Chemistry, Organic
Fuying Zhu, Yamei Lin
Summary: In this study, a low-metal iron-supported catalyst (Fe20/NC-Mg) was reported for the efficient synthesis of quinoxaline compounds, using water as a solvent and without additional bases. The synergistic effect of FeNx site and Mg (OH)2 nanorods in the catalyst played a key role in achieving high yields (82-91%) in 16 examples. The gram-level synthesis and reusability of the catalysts after four cycles demonstrated its industrial application potential.
Article
Chemistry, Organic
Mikhail Kozlov, Alexey Tyurin, Andrey Dmitrenok, Vyacheslav Rusak, Aleksander Fedorov, Igor Zavarzin, Yulia Volkova
Summary: This study presents a novel and practical synthesis method for phosphorus-substituted 1,3,4-thiadiazolines using phosphorylthioformic acid hydrazides and ketones. The protocol demonstrates operational simplicity, availability of reagents, and tolerance towards different functional groups.
Article
Chemistry, Organic
Jisna Jose, Thomas Mathew
Summary: 2-Cyclopentenone and its derivatives are highly esteemed synthetic intermediates with exceptional utility in organic synthesis. They are favored structural motifs in numerous pharmaceutical drugs and natural products, highlighting their significance. The review discusses the various methods used to synthesize cyclopentenones from 2016 to 2023.