1485-98-9Relevant articles and documents
Hydrogen Bonding Networks Enable Br?nsted Acid-Catalyzed Carbonyl-Olefin Metathesis**
Anh To, Tuong,Pei, Chao,Koenigs, Rene M.,Vinh Nguyen, Thanh
, (2022/02/17)
Synthetic chemists have learned to mimic nature in using hydrogen bonds and other weak interactions to dictate the spatial arrangement of reaction substrates and to stabilize transition states to enable highly efficient and selective reactions. The activation of a catalyst molecule itself by hydrogen-bonding networks, in order to enhance its catalytic activity to achieve a desired reaction outcome, is less explored in organic synthesis, despite being a commonly found phenomenon in nature. Herein, we show our investigation into this underexplored area by studying the promotion of carbonyl-olefin metathesis reactions by hydrogen-bonding-assisted Br?nsted acid catalysis, using hexafluoroisopropanol (HFIP) solvent in combination with para-toluenesulfonic acid (pTSA). Our experimental and computational mechanistic studies reveal not only an interesting role of HFIP solvent in assisting pTSA Br?nsted acid catalyst, but also insightful knowledge about the current limitations of the carbonyl-olefin metathesis reaction.
Carbonyl-Olefin Metathesis Catalyzed by Molecular Iodine
Tran, Uyen P. N.,Oss, Giulia,Breugst, Martin,Detmar, Eric,Pace, Domenic P.,Liyanto, Kevin,Nguyen, Thanh V.
, p. 912 - 919 (2019/01/14)
The carbonyl-olefin metathesis reaction could facilitate rapid functional group interconversion and allow construction of complicated organic structures. Herein, we demonstrate that elemental iodine, a very simple catalyst, can efficiently promote this chemical transformation under mild reaction conditions. Our mechanistic studies revealed intriguing aspects of the activation mode via molecular iodine and the iodonium ion that could change the previously established perception of catalyst and substrate design for the carbonyl-olefin metathesis reaction.
Base-Promoted/Gold-Catalyzed Intramolecular Highly Selective and Controllable Detosylative Cyclization
Zhu, Chenghao,Qiu, Lin,Xu, Guangyang,Li, Jian,Sun, Jiangtao
supporting information, p. 12871 - 12875 (2015/09/07)
A highly selective, controllable and synthetically useful base-promoted intramolecular detosylative cyclization of bis-N-tosylhydrazones has been achieved, affording N-containing heterocycles and cyclic olefins under transition-metal-free or gold-catalyzed procedures, respectively. Moreover, an effective and practical metal-free or gold-catalyzed approach to synthesize polycyclic aromatic compounds is also reported. Basic cyclizations: A highly selective, controllable, and synthetically useful base-promoted intramolecular detosylative cyclization of bis-N-tosylhydrazones affords N-containing heterocycles and cyclic olefins under transition-metal-free or gold-catalyzed procedures, respectively. Moreover, an effective and practical metal-free or gold-catalyzed approach to synthesize polycyclic aromatic compounds is also reported.
