99048-49-4Relevant academic research and scientific papers
Enantioselective Inverse Electron Demand (3 + 2) Cycloaddition of Palladium-Oxyallyl Enabled by a Hydrogen-Bond-Donating Ligand
Zheng, Yin,Qin, Tianzhu,Zi, Weiwei
, p. 1038 - 1045 (2021)
Cycloaddition reactions between oxyallyl cations and alkenes are important transformations for the construction of ring systems. Although (4 + 3) cycloaddition reactions of oxyallyl cations are well-developed, (3 + 2) cycloadditions remain rare, and an as
Rhodium-catalyzed intra- and intermolecular [5 + 2] cycloaddition of 3-acyloxy-1,4-enyne and alkyne with concomitant 1,2-acyloxy migration
Shu, Xing-Zhong,Li, Xiaoxun,Shu, Dongxu,Huang, Suyu,Schienebeck, Casi M.,Zhou, Xin,Robichaux, Patrick J.,Tang, Weiping
, p. 5211 - 5221 (2012/05/05)
A new type of rhodium-catalyzed [5 + 2] cycloaddition was developed for the synthesis of seven-membered rings with diverse functionalities. The ring formation was accompanied by a 1,2-acyloxy migration event. The five- and two-carbon components of the cycloaddition are 3-acyloxy-1,4-enynes (ACEs) and alkynes, respectively. Cationic rhodium(I) catalysts worked most efficiently for the intramolecular cycloaddition, while only neutral rhodium(I) complexes could facilitate the intermolecular reaction. In both cases, electron-poor phosphite or phosphine ligands often improved the efficiency of the cycloadditions. The scope of ACEs and alkynes was investigated in both the intra- and intermolecular reactions. The resulting seven-membered-ring products have three double bonds that could be selectively functionalized.
