825-40-1Relevant academic research and scientific papers
The intramolecular reaction of acetophenoneN-tosylhydrazone and vinyl: Br?nsted acid-promoted cationic cyclization toward polysubstituted indenes
Wang, Zhixin,Li, Yang,Chen, Fan,Qian, Peng-Cheng,Cheng, Jiang
supporting information, p. 1810 - 1813 (2021/02/27)
In the presence of TsNHNH2, a Br?nsted acid-promoted intramolecular cyclization ofo-(1-arylvinyl) acetophenone derivatives was developed, leading to polysubstituted indenes with complexity and diversity in moderate to excellent yields. In sharp contrast with either the radical or carbene involved cyclization of aldehydicN-tosylhydrazone with vinyl, a cationic cyclization pathway was involved, whereN-tosylhydrazone served as an electrophile and alkylation reagent during this transformation.
α-Oxocarboxylic Acids as Three-Carbon Insertion Units for Palladium-Catalyzed Decarboxylative Cascade Synthesis of Diverse Fused Heteropolycycles
Zhou, Liwei,Qiao, Shujia,Zhou, Fengru,Xuchen, Xinyu,Deng, Guobo,Yang, Yuan,Liang, Yun
supporting information, p. 2878 - 2883 (2021/05/05)
A novel palladium-catalyzed decarboxylative cascade cyclization for the assembly of diverse fused heteropolycycles by employing α-oxocarboxylic acids as three-carbon insertion units is reported. This protocol enables the synthesis of isoquinolinedione- and indolo[2,1-a]isoquinolinone-fused benzocycloheptanones in moderate to good yields by the use of different aryl iodides, including alkene-tethered 2-iodobenzamides and 2-(2-iodophenyl)-1H-indoles. Notably, the approach achieves simultaneous construction of both six- and seven-membered rings via sequential intramolecular carbopalladation, C-H activation, and decarboxylation.
Atmosphere-Controlled Palladium-Catalyzed Divergent Decarboxylative Cyclization of 2-Iodobiphenyls and α-Oxocarboxylic Acids
Zhou, Liwei,Sun, Mingjie,Zhou, Fengru,Deng, Guobo,Yang, Yuan,Liang, Yun
supporting information, p. 7150 - 7155 (2021/09/18)
A novel palladium-catalyzed divergent decarboxylative cyclization of 2-iodobiphenyls and α-oxocarboxylic acids utilizing the atmosphere as a controlled switch is reported. Under the protection of a nitrogen atmosphere, tribenzotropones are synthesized by a [4 + 3] decarboxylative cyclization. Employing a palladium/O2 system enables a [4 + 2] decarboxylative cyclization to assemble triphenylenes. Notably, preliminary mechanistic studies indicate that the formation of triphenylenes involves a double decarboxylation.
Asymmetric Synthesis and Application of Chiral Spirosilabiindanes
Chang, Xin,Chen, Hong-Chao,Li, Chuan-Ying,Ma, Pei-Long,Wang, Peng
supporting information, p. 8937 - 8940 (2020/04/30)
Reported here is the development of a class of chiral spirosilabiindane scaffolds by Rh-catalyzed asymmetric double hydrosilation, for the first time. Enantiopure SPSiOL (spirosilabiindane diol), a new type of chiral building block for the preparation of various chiral ligands and catalysts, was readily prepared on greater than 10 gram scale using this protocol. The potential of this new spirosilabiindane scaffold in asymmetric catalysis was preliminarily demonstrated by development of the corresponding monodentate phosphoramidite ligands (SPSiPhos), which were used in both a Rh-catalyzed hydrogenation and a Pd-catalyzed intramolecular carboamination.
PdII-Catalyzed Oxidative Tandem aza-Wacker/Heck Cyclization for the Construction of Fused 5,6-Bicyclic N,O-Heterocycles
Ye, Chenghao,Kou, Xuezhen,Xia, Jingzhao,Yang, Guoqiang,Kong, Li,Wei, Quhao,Zhang, Wanbin
supporting information, p. 1897 - 1901 (2018/07/31)
A PdII-catalyzed oxidative tandem cyclization was developed for the construction of fused 5,6-bicyclic N, O-heterocycles. This reaction was enabled by the combined use of a 3-methylpyridine ligand and pentafluorobenzoic acid additive. A range of heterocyclic products with different substituents could be prepared in moderate to good yields via this methodology. Several transformations, including a scaled-up preparation of product 2 a, were also carried out showing the good applicability of our methodology.
Preparation of isoindolinones via a palladium-catalyzed diamination
Li, Yu,Kou, Xuezhen,Ye, Chenghao,Zhang, Xinghua,Yang, Guoqiang,Zhang, Wanbin
supporting information, p. 285 - 288 (2017/01/03)
A Pd(II)-catalyzed cyclization using oxidative olefin diamination was developed for the preparation of isoindolinones from ortho-olefinic N-methoxybenzamides. Using the optimized reaction conditions, the desired products were obtained in up to 90% yield using NFSI as the oxidant. This reaction provides an efficient and direct access to isoindolinones with amine functionality, an important drug skeleton.
Enantioselective Bromo-oxycyclization of Silanol
Xia, Zilei,Hu, Jiadong,Shen, Zhigao,Wan, Xiaolong,Yao, Qizheng,Lai, Yisheng,Gao, Jin-Ming,Xie, Weiqing
supporting information, p. 80 - 83 (2016/01/15)
Relying on the nucleophilicity of silanol for building up silicon-incorporated scaffold with an enantiopure tetrasubstituted carbon center remains elusive. In this report, asymmetric bromo-oxycyclization of olefinic silanol by using chiral anionic phase-transfer catalyst is described. This protocol provided a facile entry to a wide arrangement of enantiopure benzoxasilole in moderate to excellent enantioselectivities depending on the unique reactivity of bromine/N-benzyl-DABCO complex.
Palladium-Catalyzed Aerobic Aminooxygenation of Alkenes for Preparation of Isoindolinones
Kou, Xuezhen,Li, Yu,Wu, Liang,Zhang, Xinghua,Yang, Guoqiang,Zhang, Wanbin
supporting information, p. 5566 - 5569 (2015/12/01)
A palladium-catalyzed intramolecular isoindolinone-forming aminooxygenation of alkenes with 1 atm of oxygen as oxidant is reported. A variety of functionalized alkenes and carboxylic acids can be used, and high yields were observed. Preliminary mechanistic studies revealed that the aminooxygenation products were formed through the oxidation of a C-PdII species using a strong oxidant, peroxide, which is generated in situ from a Pd(OAc)2/bpy/O2/HOAc catalytic system.
