Article
Chemistry, Organic
Marta Papis, Raffaella Bucci, Alessandro Contini, Maria Luisa Gelmi, Leonardo Lo Presti, Giovanni Poli, Gianluigi Broggini, Camilla Loro
Summary: A phosphine-catalyzed domino assembly of six units of 2-bromomethyl acrylates was developed to synthesize polyalkenyl adducts containing two cyclohexenyl rings. This method involves initial dimerization and subsequent trimerization of the substrate, resulting in the formation of seven carbon-carbon bonds and four stereocenters. The protocol has also been successfully scaled up to gram-scale experiments.
Article
Chemistry, Organic
Daqian Wang, Jing Sun, Ying Han, Qiu Sun, Chao-Guo Yan
Summary: Researchers have developed an efficient protocol for constructing polycyclic dihydrobenzofuran spirooxindole scaffolds, yielding complex cyclic compounds with high diastereoselectivity. This method provides a swift and convenient approach for assembling diverse highly functionalized dihydrobenzofuran spirooxindoles and features broad substrate scope, high molecular convergence, and excellent atomic economy.
Article
Chemistry, Organic
Mengzhou Wang, Jing Wang, Wen Shen, Xuan-sheng Xie, Liang Qi, Jian-wu Xie
Summary: A diastereoselective and enantioselective formal [4+1] ylide annulation of chiral sulfonium salts with various substituted Morita-Baylis-Hillman (MBH) adducts has been investigated, leading to optically active isoxazoline N-oxides with three chiral carbon centers. The method has notable features of high diastereo- and enantioselective transformation, easily accessible starting materials, and mild reaction conditions. Moreover, the isoxazoline N-oxides products can be conveniently converted into functionalized compounds.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Xing Guo, Boming Shen, Chang Liu, Hongyue Zhao, Xuechen Li, Peiyuan Yu, Pengfei Li
Summary: Based on the frontier molecular orbital theory, two types of modified enones have been designed and successfully applied in the chiral phosphine-catalyzed stereoselective [1 + 4]-annulation of MBH carbonates. The reaction proceeds smoothly under mild conditions, exhibiting excellent functional group tolerance and providing a broad scope of enantioenriched 2,3-dihydrofurans with high efficiency. DFT calculations have been used to guide the design of additional enones and understand the origin of stereoselectivity. Furthermore, this method explores the application scope of enones and enriches the chemistry of [1 + 4]-annulations of MBH carbonates for the preparation of optically active multifunctional 2,3-dihydrofurans.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Multidisciplinary
Deevi Basavaiah, Gangadhararao Golime, Shivalal Banoth, Saidulu Todeti
Summary: This study presents the first example of an umpolung strategy for intermolecular [2 + 2 + 1] cycloaddition between two aryl aldehydes and a nitrile, resulting in the formation of N-C, O-C, and C-C bonds and providing a straightforward synthetic protocol for obtaining 2,4,5-trisubstituted oxazoles.
Article
Chemistry, Multidisciplinary
Dragana Stevanovic, Jovana Bugarinovic, Marko Pesic, Anka Todosijevic, Goran A. Bogdanovic, Ivan Damljanovic
Summary: A simple protocol has been developed for the synthesis of multifunctional ferrocene derivatives. The study showed that the strong electron-donating group at the beta-position of nitroalkenes prevents polymerization and stabilizes the intermediate.
Article
Chemistry, Organic
Huamin Wang, Yibo Wei, Yuqiang Li, Shuangshuang Long, Li-Juan Sun, Shixiong Li, Ying-Wu Lin
Summary: A new strategy for the enantioselective synthesis of axially chiral N-aryl succinimides was developed using [3 + 2] annulation of MBH carbonates and N-aryl maleimides under chiral phosphine. This process allows for the efficient construction of stereogenic carbon centers and remote C-Ar-N atropisomeric chirality. The method exhibits mild reaction conditions, high efficiency, scalability, and a broad substrate scope.
Article
Chemistry, Multidisciplinary
Bo Wang, Yimin Hu, Hongchao Guo, Lei Tao
Summary: Various multifunctional chromone-spiroindolinone-cyclopentene derivatives were synthesized through a phosphine-catalyzed reaction, showing excellent diastereoselectivities and potential application in the synthesis of biologically important compounds.
Article
Chemistry, Organic
Jing Sun, Xueyan Liu, Qiu Sun, Ying Han, Chao-Guo Yan
Summary: Diverse functionalized dihydrobenzofuran spiro-indanedione scaffolds were synthesized via base-promoted cyclization reaction. The selective synthesis of two diastereomeric dispiro[indene-2,1′-cyclopenta[b]benzofuran-2,3′-indolines] was achieved using DABCO or DMAP as a base promoter. Moreover, DABCO or DMAP facilitated the annulation reaction of MBH formates, resulting in the formation of spiro[cyclopropa[c]chromene-1,2′-indene]-1′,3′-diones or dispiro[indene-2,1′-cyclopenta[b]benzofuran-2,3′-indolines]. Additionally, high-yielding and highly diastereoselective synthesis of dispiro[indene-2,5′-benzofuro[2′,3′:1,5]cyclopenta[1,2-c]pyrrole-4′,3″-indolines] was achieved using MBH maleimides.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Jianning Liao, Jipan Dong, Jiaqing Xu, Wei Wang, Yongjun Wu, Yuxia Hou, Hongchao Guo
Summary: A phosphine-catalyzed [3 + 2] annulation reaction has been developed in this study to synthesize multifunctional isoxazoles with moderate to good yields and diastereoselectivities. The use of a spirocyclic chiral phosphine catalyst resulted in up to 89% ee.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Bao-Xin Liu, Ru-Jie Yan, Xiao-Xun Li, Wei Du, Ying-Chun Chen
Summary: Aurones and their analogues are useful in constructing valuable spiroheterocycles. The Morita-Baylis-Hillman carbonates of isatins can efficiently combine with thioaurones, aurones, or methyleneindolinones to produce a wide range of densely functionalized spiro-benzothiophene, -benzofuran, and bisspirooxindole frameworks with high yields and good to excellent stereoselectivity.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Juan Ye, Yilu Luo, Gailing Huang, Yang Wang
Summary: The detailed mechanism and role of the catalyst in the PPh3-catalyzed [3+6] annulation reaction of MBH carbonate and dicyanoheptafulvene were systematically investigated using a DFT method. The C-O bond cleavage was found to be the rate-determining step, while the reaction between allylic phosphorus ylide and dicyanoheptafulvene determined the regioselectivity with α-addition occurring prior to γ-addition. PPh3 promoted the release of BocO(-) anions primarily by alleviating the electron density between the Cγ-O1 bonds.
NEW JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Organic
Hongxiang Li, Wangyu Shi, Chang Wang, Hao Liu, Wei Wang, Yongjun Wu, Hongchao Guo
Summary: A successful phosphine-catalyzed cascade annulation of Morita-Baylis-Hillman (MBH) carbonates and diazenes was achieved, giving tetrahydropyrazole-fused heterocycles bearing two five-membered rings in moderate to excellent yields. The reaction exhibited an unprecedented reaction mode of MBH carbonates, where two molecules of MBH carbonates were fully incorporated into the ring system.
Article
Chemistry, Organic
Xi Chen, Min Liu, Jiaqing Xu, Lei Wang, Songcheng Yu, Yongjun Wu, Jiaxing Huang, Hongchao Guo
Summary: A phosphine-catalyzed (3+2) annulation of Morita-Baylis-Hillman carbonates with pyrazolinone-derived ketimines has been achieved to give a variety of functionalized spirodihydropyrrole-dihydropyrazolones in moderate to high yields with good diastereoselectivities.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Sudheesh T. Sivanandan, Diksha Chauhan, Irishi N. N. Namboothiri
Summary: This article introduces a mild and metal-free method for the one-pot synthesis of highly substituted tetrahydro-alpha-carbolines. The method utilizes a cascade reaction to form various tetrahydro-alpha-carbolines with high yields and regio- as well as diastereoselectivity under mild conditions.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
