Article
Chemistry, Organic
Can Gao, Ting Zhang, Xiaoxun Li, Jing-De Wu, Jitian Liu
Summary: A new asymmetric reaction strategy for the synthesis of enantiomerically enriched and polycyclic molecules has been reported. By using a newly designed catalyst, high yields and high selectivities were achieved. This method offers mild reaction conditions and good functional group tolerance, making it important for the synthesis of organic compounds.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Organic
Anais Scuiller, Nicolas Casaretto, Alexis Archambeau
Summary: Cycloaddition reactions have been widely used to synthesize lactams and other N-heterocycles, but enantioselective versions are limited. In this study, we introduce 5-vinyloxazolidine-2,4-diones as a precursor for a new palladium-π-allylpalladium intermediate. By utilizing electrophilic alkenes, (3 + 2) γ-lactam cycloadducts can be formed with high levels of diastereo- and enantioselectivity.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Benjamin Murray, Shibin Zhao, James M. Aramini, Hsin Wang, Mark R. Biscoe
Summary: Using deuterium-labeled stereochemical probes, it was found that primary alkyltrifluoroborate nucleophiles exclusively undergo transmetalation to palladium via a stereoretentive pathway, while the stereochemical course of transmetalation for secondary alkyltrifluoroborates is influenced by the electronic and steric effects of the supporting ligands.
Article
Chemistry, Physical
Garrett P. R. Freure, Eric A. Skrotzki, Jean-Danick E. Lavertu, Stephen G. Newman
Summary: Various methods have been investigated recently for the arylation of weakly acidic C(sp(3))-H bonds, with this study focusing on a base-mediated approach using organometallic superbases. The study developed conditions for high selectivity metalation using either n-BuLi/diamine or n-BuLi/KOtBu superbases, allowing for direct use in cross-coupling or formation of organozincs for reactions with functional groupdense organohalides.
Article
Chemistry, Multidisciplinary
Haipin Zhou, Rui Pan, Menghua Xu, Jiao Ma, Aijun Lin, Hequan Yao
Summary: In this study, a palladium-catalyzed 1,2-aminoacyloxylation of cyclopentenes is described for the synthesis of oxygenated 2-azabicyclo[2.2.1]heptanes. This reaction shows high efficiency with a wide range of substrates and the resulting products can be further functionalized to create a library of bridged aza-bicyclic structures.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Sofia O. Samultceva, Marina Yu Dvorko, Dmitrii A. Shabalin, Igor' A. Ushakov, Alexander V. Vashchenko, Elena Yu Schmidt, Boris A. Trofimov
Summary: 6-Methylene-5-oxaspiro[2.4]heptanones have been successfully synthesized via base-catalyzed dimerization of available alkynyl cyclopropyl ketones. The reaction proceeds at room temperature in the presence of the t-BuOK/t-BuOH/THF catalytic system, providing the desired spirocycles in a regio- and stereoselective manner. The study also demonstrates the wide synthetic utility of alkynyl cyclopropyl ketones as novel building blocks.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Kuan Li, Shuo Zhen, Wang Wang, Juan Du, Songcheng Yu, Yongjun Wu, Hongchao Guo
Summary: Inspired by a fungicide, we designed 5-vinyloxazolidine-2,4-diones as new precursors of pi-allylpalladium zwitterionic intermediates and developed palladium-catalyzed asymmetric (5 + 3) cycloaddition with azomethine imines and (3 + 2) cycloaddition with 1,1-dicyanoalkenes. Both reactions proceeded smoothly under mild reaction conditions to produce various chiral heterocyclic compounds in high yields with excellent enantioselectivities. These results revealed that 5-vinyloxazolidine-2,4-diones were a type of suitable precursor for palladium catalysis and will find extensive applications in Pd-catalyzed reactions such as cycloaddition and allylic alkylation.
Article
Chemistry, Organic
Juyeol Lee, Young Ho Rhee
Summary: This study presents a palladium-catalyzed polar inversion reaction where glycals and their isomers can act as nucleophiles. The reaction exhibits high regio- and stereoselectivity in the presence of various aromatic and aliphatic aldehydes, demonstrating its synthetic utility in the concise synthesis of the tetrahydropyran fragment of the anticancer natural product mucocin.
Article
Chemistry, Organic
Ling Liao, Zhi-Peng Zhao, Bo-Ning Gu, Jin-Sheng Yu, Jian Zhou
Summary: Researchers have developed a branch-selective hydroalkylation method using palladium catalysis for the reaction between alkoxyallenes and monofluorinated nucleophiles. This allows the construction of valuable α-monofluoroalkylated allylic ethers. It is the first catalytic hydrofluoroalkylation of alkoxyallenes and demonstrates broad substrate scope and diversified product elaborations. The asymmetric variant of this method also showed the potential to obtain chiral fluorine-containing allylic ethers with up to 68% enantiomeric excess.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Organic
Shu-Pei Yuan, Qing Bao, Ting-Jia Sun, Jian-Qiang Zhao, Zhen-Hua Wang, Yong You, Yan-Ping Zhang, Ming-Qiang Zhou, Wei-Cheng Yuan
Summary: A palladium-catalyzed enantioselective alpha-allylation reaction has been developed, leading to the synthesis of a series of nitrogen-containing compounds with an all-carbon quaternary stereocenter. The method demonstrated high yields and excellent enantioselectivities, and its utility was showcased through large-scale reactions and synthetic transformations of the products.
Review
Chemistry, Organic
Hans-Joachim Gais
Summary: Allylic oxygen compounds are versatile building blocks in synthesis. Catalytic deracemization is an attractive method for their enantioselective synthesis. This review discusses the palladium-catalyzed and iridium-catalyzed dynamic kinetic asymmetric transformations of allylic oxygen compounds with various nucleophiles.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Review
Chemistry, Multidisciplinary
Xi Wang, Youbin Peng, Ling Zhao, Xiaohong Huo, Wanbin Zhang
Summary: Compared to the stereocontrol of the stereocenter at the allyl unit, asymmetric induction of prochiral nucleophiles is a challenging task in Pd-catalyzed asymmetric allylic substitutions due to the remote distance between the chiral catalyst and the prochiral nucleophile. Extensive efforts have been made to address this challenge through the design of chiral ligands. Recently, synergistic catalysis, including bimetallic catalysis and Pd/organocatalysis, has gained attention for its potential advantages in improving reactivity and selectivity, and providing a simple and unified method for the stereocontrol of prochiral nucleophiles. This review summarizes the history and advances in this field.
SCIENCE CHINA-CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Katie A. Spence, Jason Chari, Mattia Di Niro, Robert B. Susick, Narcisse Ukwitegetse, Peter Djurovich, Mark E. Thompson, Neil K. Garg
Summary: This paper reports a method for accessing pi-extended polycyclic aromatic hydrocarbons (PAHs) through the annulation of heterocyclic building blocks. The utility of this method in the synthesis and study of organic materials is demonstrated.
Article
Chemistry, Organic
Zipeng Wang, Tongxiang Cao, Shifa Zhu
Summary: The coupling reaction of enynal and enynol catalyzed by gold has been achieved by selectively steering two transient vinyl-gold intermediates, showing high atom economy and good tolerance of functional groups, with the reactivity being determined by the in situ formed vinyl-gold.
Article
Chemistry, Multidisciplinary
Ben Niu, Yin Wei, Min Shi
Summary: The palladium-catalyzed divergent synthesis involves the cycloaddition reaction of vinylidenecyclopropane-diesters with methyleneindolinones to form spirooxindoles fused with a five- or a six-membered ring. This protocol features an unprecedented zwitterionic pi-propargyl palladium species in cycloaddition reactions and a switchable process between (3+2) and (4+2) cycloadditions by changing the phosphine ligand, providing high synthetic flexibility and operability.
CHEMICAL COMMUNICATIONS
(2021)
