Palladium‐Catalyzed Formal Hydroalkylation of Aryl‐Substituted Alkynes with Hydrazones
作者:Lin Yu、Leiyang Lv、Zihang Qiu、Zhangpei Chen、Ze Tan、Yu‐Feng Liang、Chao‐Jun Li
DOI:10.1002/anie.202005132
日期:2020.8.10
naturally abundant aldehydes, as both alkylation reagents and hydrogen donors. The hydroalkylation proceeds with high regio‐ and stereoselectivity to form (Z )‐alkenes, which are more difficult to generate compared to (E )‐alkenes. The reaction is compatible with a wide range of functional groups, including hydroxy, ester, ketone, nitrile, boronicester, amine, and halide groups. Furthermore, late‐stage modifications
Ligand-, Copper-, and Amine-Free Sonogashira Reaction of Aryl Iodides and Bromides with Terminal Alkynes
作者:Sameer Urgaonkar、John G. Verkade
DOI:10.1021/jo049325e
日期:2004.8.1
and amine-free palladium-catalyzed Sonogashirareaction of aryl iodides and bromides with terminal alkynes have been developed. Critical to the success of this new protocol is the use of tetrabutylammonium acetate as the base. Noteworthy features of this method are room-temperature conditions and the tolerance of a broad range of functional groups in both reaction partners.
A simple catalytic method involving all‐metal aromatic frameworks as precatalysts ensures an efficient route to (Z)‐alkenes. Aromatic triangular palladium clusters were used to reduce internalalkynes without any trace of the formation of alkane side products. These trinuclear complexes provide a catalytic system that parallels the activity and selectivity of their best mononuclear peers, and the catalyst
The synthesis of pyridines through direct intermolecular cycloaddition of alkynes and nitriles is a contemporary challenge in organic synthesis. A Brønsted acid mediated formal [2+2+2] cycloaddition of heteroalkynes and nitriles was developed that proceeds under mild conditions. This constitutes a modular approach to highly substituted pyridine cores.
Cobalt-catalysed synthesis of highly substituted styrene derivatives via arylzincation of alkynes
作者:Martin Corpet、Corinne Gosmini
DOI:10.1039/c2cc36676b
日期:——
A new two-step procedure was developed by carbozincation of internal and terminal alkynes to synthesise highly functionalised vinylzinc bromides. Various tri and tetrasubstituted alkenes were prepared in moderate to good yields under mild reaction conditions in a stereo-selective manner. This methodology represents an interesting alternative to previously known methods.