α-bromocarbonyls for the synthesis of various cyclohexenone-fused polycyclic compounds is described. Up to six new C–C bonds and four new carbocycles can be established in a single reaction, highlighting the high efficiency and step-economics of this protocol. This reaction offers a novel and straightforward entry to the synthesis of ketones featuring the addition of carbon radicals to aldehydes.
Rhodium(II)-Catalyzed Intramolecular Cycloisomerizations of Methylenecyclopropanes with<i>N</i>-Sulfonyl 1,2,3-Triazoles
作者:Kai Chen、Zi-Zhong Zhu、Yong-Sheng Zhang、Xiang-Ying Tang、Min Shi
DOI:10.1002/anie.201402803
日期:2014.6.23
A novel rhodium(II)‐catalyzed tandem cycloisomerization of methylenecyclopropanes (MCPs) with N‐sulfonyl 1,2,3‐triazoles is disclosed. The reaction produces a series of highly functionalized polycyclic N heterocycles via a rhodium imino carbene intermediate. A distinct feature of this divergent synthesis is that different types of substrates control the reaction pathways. Moreover, several interesting
Palladium-Catalyzed Chemoselective Aminomethylative Cyclization and Aromatizing Allylic Amination: Access to Functionalized Naphthalenes
作者:Bangkui Yu、Houjian Yu、Hanmin Huang
DOI:10.1021/acs.orglett.0c03365
日期:2020.11.20
A palladium-catalyzedchemoselective aminomethylative cyclization and aromatizing allylic amination of enyne-tethered allylic alcohols with aminals is described. Under the reaction conditions, the cationic vinyl allylpalladium species undergoes selective migratory insertion of alkenes rather than reductive elimination with nucleophiles. This strategy provides an efficient and unique approach to the
Palladium-Catalyzed Aminomethylative Oppolzer-Type Cyclization of Enynes: Access to Aminomethylated Benzofulvenes
作者:Renbin Huang、Bangkui Yu、Renren Li、Hanmin Huang
DOI:10.1021/acs.orglett.1c03720
日期:2021.12.17
A novel palladium-catalyzed Oppolzer-type cyclization reaction aided by the aminomethyl cyclopalladated complex has been developed, which provides rapid access to functionalized benzofulvenes with excellent stereoselectivity. The corresponding products can undergo Diels–Alder reaction with maleimides, providing a series of complex polycyclic compounds with excellent regio- and stereoselectivities.
A catalytic [1,3] O‐to‐C rearrangement from enyne‐ethers was developed for the rapid synthesis of diverse bridged bicyclic systems. In this reaction, a vinyl oxonium intermediate, generated in situ from enyne‐ether, was the precursor for the [1,3] O‐to‐C rearrangement. This versatile protocol represents the first example of catalytic [1,3] O‐to‐C rearrangement based on ring‐expansion strategy, enabling