1644060-33-2Relevant academic research and scientific papers
Asymmetric Synthesis of N-Fused 1,3-Oxazolidines via Pd-Catalyzed Decarboxylative (3+2) Cycloaddition
Ahn, Hye-In,Cho, Ho-Jun,Kim, Ju Hyun,Park, Jong-Un,Xuan, Zi
, (2020)
Efficient synthesis of optically active N-fused 1,3-oxazolidines containing quaternary and tertiary stereocenters was achieved via Pd-catalyzed asymmetric (3+2) cycloadditions of sulfamate-derived cyclic imines and vinylethylene carbonates. Using a chiral phosphoramidite ligand, the cycloadditions proceeded effectively providing sulfamidate-fused 1,3-oxazolidines in high yields (up to 96%) with stereoselectivities (up to 25:1 dr; >99% ee). Additionally, the scale-up reaction and further transformations of the product were also achieved demonstrating the synthetic utility toward the construction of useful heterocycles such as chiral oxazoline bearing a quaternary stereocenter. (Figure presented.).
Asymmetric Synthesis of 2,2-Difluorotetrahydrofurans through Palladium-Catalyzed Formal [3+2] Cycloaddition
Liu, Jun,Yu, Longhui,Zhao, Gang,Zheng, Changwu
supporting information, p. 23641 - 23645 (2021/10/05)
The asymmetric synthesis of 2,2-difluorinated tetrahydrofurans was accomplished via enantioselective formal [3+2] cycloaddition catalyzed by palladium. The asymmetric reaction between gem-difluoroalkenes and racemic vinyl epoxides or vinylethylene carbonates resulted in the formation of enantioenriched 2,2-difluorotetrahydrofurans with an enantioselectivity up to 98 %. Notably, the reaction used the readily available (R)-BINAP as the ligand at a low loading and yielded a wide variety of difluorinated products in moderate to high yields. Both chiral diastereomers could be obtained in a single sequence.
Palladium-catalyzed stereoselective (3 + 2) cycloaddition of vinylethylene carbonates with cyclicN-sulfonyl ketimines
Gao, Xing,Zhu, Dongyu,Jiang, Feng,Liao, Jianning,Wang, Wei,Wu, Yongjun,Zheng, Lufei,Guo, Hongchao
supporting information, p. 4877 - 4881 (2021/06/16)
A diastereoselective (3 + 2) cycloaddition ofN-sulfonyl ketimines with vinylethylene carbonates (VECs) in the presence of Pd2dba3·CHCl3and PPh3has been developed. The reaction of various substituted VECs and diverse cyclicN-sulfonyl ketimines proceeded smoothly under mild conditions, giving highly functionalized oxazolidine frameworks in good to excellent yields with moderate to good diastereoselectivities. With the use of spiroketal-based diphosphine SKP as a chiral ligand, an asymmetric version of the current (3 + 2) cycloaddition was achieved, and chiral products were obtained in >99% ee in most cases.
Chiral Bidentate Phosphoramidite-Pd Catalyzed Asymmetric Decarboxylative Dipolar Cycloaddition for Multistereogenic Tetrahydrofurans with Cyclic N-Sulfonyl Ketimine Moieties
Lv, Hao-Peng,Yang, Xiao-Peng,Wang, Bai-Lin,Yang, Hao-Di,Wang, Xing-Wang,Wang, Zheng
supporting information, p. 4715 - 4720 (2021/06/28)
An asymmetric [3 + 2] cycloaddition of vinyl ethylenecarbonates (VECs) and (E)-3-arylvinyl substituted benzo[d] isothiazole 1,1-dioxides has been developed using the Pd complex of a bidentate phosphoramidite (Me-BIPAM) as the catalyst, providing a wide variety of chiral multistereogenic vinyltetrahydrofurans in good yields with excellent diastereo- and enantioselectivities (up to >20:1 dr, 99% ee).
Asymmetric Synthesis of Multi-Substituted Tetrahydrofurans via Palladium/Rhodium Synergistic Catalyzed [3+2] Decarboxylative Cycloaddition of Vinylethylene Carbonates
Ming, Siliang,Qurban, Saira,Du, Yu,Su, Weiping
supporting information, p. 12742 - 12746 (2021/07/28)
Unlike the comprehensive development of tandem multi-metallic catalysis, bimetallic synergistic catalysis has been challenging to achieve high stereoselectivity with the generation of multi-stereogenic centers. Herein, an efficient synergistic catalysis for the diastereo- and enantioselective synthesis of multi-substituted tetrahydrofuran derivatives has been developed. Under mild reaction conditions, a series of target molecules with three consecutive stereocenters were synthesized by a palladium(0)/rhodium(III) bimetal-catalyzed asymmetric decarboxylative [3+2]-cycloaddition of vinylethylene carbonates with α,β-unsaturated carbonyl compounds. The corresponding adducts were obtained with moderate to high yields (67 %~98 %) and excellent stereoselectivities (>20 : 1 d.r., up to 99 % ee).
Pd-Catalyzed Decarboxylative Olefination: Stereoselective Synthesis of Polysubstituted Butadienes and Macrocyclic P-glycoprotein Inhibitors
Chen, Xiangyang,Hao, Jiping,Houk, K. N.,Li, Yingzi,Lou, Liguang,Quan, Haitian,Song, Bichao,Wang, Lu,Xia, Yuanzhi,Xie, Peipei,Xu, Zhongliang,Yang, Weibo
supporting information, p. 9982 - 9992 (2020/06/27)
The efficient and stereoselective synthesis of polysubstituted butadienes, especially the multifunctional butadienes, represents a great challenge in organic synthesis. Herein, we wish to report a distinctive Pd(0) carbene-initiated decarboxylative olefination approach that enables the direct coupling of diazo esters with vinylethylene carbonates (VECs), vinyl oxazolidinones, or vinyl benzoxazinones to afford alcohol-, amine-, or aniline-containing 1,3-dienes in moderate to high yields and with excellent stereoselectivity. This protocol features operational simplicity, mild reaction conditions, a broad substrate scope, and gram-scalability. Notably, a structurally unique allylic Pd(II) intermediate was isolated and characterized. DFT calculation and control experiments demonstrated that a rare Pd(0) carbene intermediate could be involved in this reaction. Moreover, the polysubstituted butadienes as novel building blocks were unprecedentedly assembled into macrocycles, which efficiently inhibited the P-glycoprotein and dramatically reversed multidrug resistance in cancer cells by 190-fold.
Palladium-Catalyzed Asymmetric [3+2] Cycloaddition of Vinylethylene Carbonates with 2-Arylidene-1,3-Indandiones: Synthesis of Tetrahydrofuran-Fused Spirocyclic 1,3-Indandiones
Gao, Xing,Guo, Hongchao,Jiang, Feng,Shi, Wangyu,Shi, Xueyan,Wang, Wei,Wu, Yongjun,Zhang, Cheng,Zhang, Huihui
supporting information, (2020/08/06)
An asymmetric [3+2] cycloaddition of 2-arylidene-1,3-indandiones with vinylethylene carbonates (VECs) had been achieved in the presence of Pd2dba3·CHCl3 and axially chiral phosphoramidite ligand. The reaction of various su
Palladium-Catalyzed [5 + 2] Annulation of Vinylethylene Carbonates with Barbiturate-Derived Alkenes
Chen, Yuehua,Deng, Hao,Gao, Xing,Guo, Hongchao,Jiang, Feng,Wang, Wei,Wu, Yongjun,Zhu, Dongyu
supporting information, p. 7158 - 7163 (2020/10/02)
A palladium/XantPhos-catalyzed [5 + 2] annulation of VECs with electron-deficient alkenes having an isolated carbon-carbon double bond has been developed to afford spirobarbiturate-tetrahydrooxepines. This study provides an expedient assembly of biologically interesting spirobarbiturate-tetrahydrooxepines. The easy scalability and versatile transformability of the reaction products were also exhibited.
Palladium-catalyzed regio- And stereoselective access to allyl ureas/carbamates: Facile synthesis of imidazolidinones and oxazepinones
Banerjee, Prabal,Saha, Debarshi,Taily, Irshad Maajid
supporting information, p. 6564 - 6570 (2020/11/10)
Typically, transition metal catalysis enforces the stereodefined outcome of a reaction. Here we disclose the palladium-catalyzed regio- and stereoselective access to allylic ureas/carbamates and their further exploitation to diverse cyclic structures under operationally simple reaction conditions. This protocol features palladium-catalyzed decarboxylative amidation of highly modular VECs with good to excellent yield, minimal waste production, wide substrate scope, and low catalyst loading. In follow-up chemistry, we demonstrated the debenzylation of vinylic imidazolidinones to N-hydroxycyclic ureas and regioselective derivatization towards the facile synthesis of halohydrins and oxiranes under mild reaction conditions in good to excellent yields. This journal is
Vinylethylene Carbonates as α,β-Unsaturated Aldehyde Surrogates for Regioselective [3 + 3] Cycloaddition
Xu, Yi,Chen, Lu,Yang, Yu-Wen,Zhang, Zhiqiang,Yang, Weibo
supporting information, p. 6674 - 6678 (2019/09/03)
Herein, we report a novel stepwise addition-controlled ring size method, to access tetrahydropyrimidines through an operationally simple [3 + 3] cycloaddition of vinylethylene carbonates with triazinanes. Interestingly, we could also use this method for a [3 + 3] oxidative cycloaddition, which allows the facile synthesis of polysubstituted terphenyls under mild conditions. Mechanistic studies suggest that vinylethylene carbonates could generate α,β-unsaturated aldehydes as 3-carbon synthons for cycloaddition via a combination process of Pd-catalyzed decarboxylation and β-H elimination.
