Copper-Catalyzed Divergent Trifluoromethylation/Cyclization of Unactivated Alkenes
作者:Jing Zheng、Ziyang Deng、Yan Zhang、Sunliang Cui
DOI:10.1002/adsc.201500965
日期:2016.3.3
Most of the precedent copper‐catalyzed trifluoromethylation reactions of unactivatedalkenes concern terminalalkenes, and these processes are terminated in elimination, or nucleophilic addition, or semipinacol rearrangement, or CH bond functionalization steps. In this study, we develop a trifluoromethylation method for both unactivatedterminal and internal alkenes to enable divergent late‐stage
A newly designed radical cascade involving N-acyl cyanamides is reported. It builds on aromatic homolytic substitutions as intermediate events and leads to complex heteroaromatic structures via an unprecedented radical migration of a substituent on aryl groups of quinazolinones (hydrogen or alkyl). Mechanistic considerations are detailed, which allowed us to devise fine control over the domino processes
A copper-catalyzed difluoroalkylation of an alkene/nitrile insertion/cyclization tandem sequence of N-cyanamide alkene was described, which provided a convenient synthetic approach for accessing difluorinated bicyclic amidines bearing imine moieties in a sustainable fashion. This protocol is characterized by high yields, a broad substrate scope, and good functional group compatibility. In addition
A silver catalyzed domino reaction of <i>N</i>-cyanamide alkenes and 1,3-dicarbonyls for the synthesis of quinazolinones
作者:Gang Xu、Chaodi Tong、Sunliang Cui、Liyan Dai
DOI:10.1039/c8ob01252k
日期:——
A silvercatalyzed domino reaction of N-cyanamide alkenes and 1,3-dicarbonyls including 1,3-diketones and ethyl acetoacetate has been developed for the facile synthesis of quinazolinones. In the presence of AgNO3/K2S2O8, the diketones could be converted to radicals and coupled with N-cyanamide alkenes to undergo a cyclizationcascade for accessing quinazolinones. This method features mild reaction
已经开发出银催化的N-氰酰胺链烯烃和包括1,3-二酮和乙酰乙酸乙酯的1,3-二羰基的多米诺反应,以方便地合成喹唑啉酮。在存在AgNO 3 / K 2 S 2 O 8的情况下,二酮可转化为自由基,并与N-氰酰胺链烯偶联,经历环化级联反应,从而获得喹唑啉酮。该方法具有温和的反应条件,易于获得的起始原料以及有价值的合成实用性。而且,产物可以进一步转化成各种杂环。
Access to N-Fused Quinazolinones by Radical-Promoted Cascade Annulations of Alkenyl N-Cyanamides with Aromatic Aldehydes
A cascaderadicalcyclization of alkenyl N-cyanamides with aromatic aldehydes has been achieved for an expeditious synthesis of keto-methylated dihydropyrrolo-quinazolinones. Benzoyl radicals, generated from aryl aldehydes in the presence of di-tert-butyl peroxide (DTBP), promoted the domino annulations leading to distinctive functionalized quinazolinones in good yields. In addition, the robustness