Rhodium(III)-Catalyzed Selective Monoarylation of β or γ C(sp3)–H Bonds Assisted by a Trimethylpyrazole Group
摘要:
The selective arylation of unactivated beta or challenging gamma primary and secondary beta-C(sp(3))-H bonds has been developed with a Cp*Rh(III) catalyst assisted by a trimethylpyrazole group. A rarely reported six-membered, rhodacycle has been identified in rhodium-catalyzed C(sp(3))-H activation reactions. Preliminary mechanistic studies have revealed that a concerted metalation-deprotonation pathway might be involved in the C-H activation step.
Nickel-Catalyzed Efficient and Practical Suzuki−Miyaura Coupling of Alkenyl and Aryl Carbamates with Aryl Boroxines
作者:Li Xu、Bi-Jie Li、Zhen-Hua Wu、Xing-Yu Lu、Bing-Tao Guan、Bi-Qin Wang、Ke-Qing Zhao、Zhang-Jie Shi
DOI:10.1021/ol9029534
日期:2010.2.19
Suzuki−Miyaura coupling of unactivated alkenyl carbamates is described to construct polysubstituted olefins. The developed process is also suitable for heteroaromatic and even electron-richaromatic carbamates.
Palladium(II)-Catalyzed Enantioselective Synthesis of α-(Trifluoromethyl)arylmethylamines
作者:Thomas Johnson、Bo Luo、Mark Lautens
DOI:10.1021/acs.joc.6b00657
日期:2016.6.17
We describe a method for the synthesis of α-(trifluoromethyl)arylmethylamines that consists of the palladium(II)-catalyzed addition of arylboroxines to imines derived from trifluoroacetaldehyde. Palladium acetate is used as a catalyst with electron-neutral or electron-rich arylboroxines, and it was found that addition of an ammonium or silver salt was crucial to promote the reaction of electron-poor
A benzo[b]thiophene synthesis by Rh‐catalyzedthree‐component coupling reaction of arylboronic acids, alkynes, and elemental sulfur (S8) is developed. A notable feature of this protocol is that the thienannulation (thiophene annulation) proceeds with high regioselectivity via the sequential alkyne insertion, C−H activation, and then sulfur atom transfer to the metallacycle intermediate. In a similar
开发了通过Rh催化的芳基硼酸,炔烃和元素硫(S 8)的三组分偶联反应合成苯并[ b ]噻吩。该协议的一个显着特征是,噻吩环化(噻吩环化)通过顺序的炔烃插入,CH活化以及随后的硫原子转移至金属环中间体而以高区域选择性进行。可以类似的方式,由母体联芳基硼酸和S 8合成二苯并噻吩。
Secondary-sphere modification in proline catalysis: old friend, new connection
作者:Ido Domb、Danilo M. Lustosa、Anat Milo
DOI:10.1039/d1cc05589e
日期:——
reactivity and selectivity of amino catalysts. Herein, the carboxylic acid moiety of proline was targeted as a site for modification under catalytic reaction conditions with boronic acids. Intermolecular aldolreactions between aromatic aldehydes and cyclopentanone were selected as a proof-of-concept because cyclopentanone as an aldol donor was often associated with decreased selectivity compared to its
Nickel-catalyzed arylative substitution of homoallylic alcohols
作者:Hai N. Tran、Chau M. Nguyen、Mason T. Koeritz、Dustin D. Youmans、Levi M. Stanley
DOI:10.1039/d2sc01716d
日期:——
Direct coupling of unactivated alcohols remains a challenge in synthetic chemistry. Current approaches to cross-coupling of alcohol-derived electrophiles often involve activated alcohols such as tosylates or carbonates. We report the direct arylative substitution of homoallylic alcohols catalyzed by a nickel-bisphosphine complex as a facile method to generate allylic arenes. These reactions proceed