Nickel-Catalyzed Reductive Cross-Coupling of Vinyl Bromides with Unactivated Alkyl Halides
作者:Qun Qian、Kunhua Lin、Hegui Gong、Jun Gu、Canbin Qiu、Wenbin Lu
DOI:10.1055/s-0036-1588132
日期:——
ligand for the reductive vinylation of unactivated secondary alkyl halides under Ni-catalyzed conditions has been developed. Both alkyl- and aryl-substituted vinyl bromides are suitable, in which alkyl-decorated α-alkenyl bromides resulted in the α-products in good results. The use of pyridine as the sole ligand for the reductive vinylation of unactivated secondary alkyl halides under Ni-catalyzed conditions
Let the sunshine in! Unactivated alkyl and aryl bromides underwent a light‐enabled reductive radical cyclization in the presence of a dimeric phosphine–gold complex as a photocatalyst (see scheme; X=C(CO2Et)2, NR, O). Sunlight can be used as the energy source for this simple and efficient radical reaction, which does not require potentially hazardous and toxic chemical reagents, such as organostannanes
让阳光照进来!未活化的烷基和芳基溴化物在二聚膦-金络合物作为光催化剂的情况下进行了光活化的还原性自由基环化反应(见方案; X = C(CO 2 Et)2,NR,O)。阳光可以用作此简单有效的自由基反应的能源,该自由基反应不需要潜在危险和有毒的化学试剂,例如有机锡和化学引发剂。
Palladium-Catalyzed Carbocyclizations of Unactivated Alkyl Bromides with Alkenes Involving Auto-tandem Catalysis
作者:Alexander R. O. Venning、Megan R. Kwiatkowski、Joan E. Roque Peña、Brendan C. Lainhart、Akil A. Guruparan、Erik J. Alexanian
DOI:10.1021/jacs.7b06794
日期:2017.8.23
carbocyclization of unactivated alkyl bromides with alkenes is described. This approach uses a commercially available bisphosphine ligand and avoids the use of carbon monoxide atmosphere present in prior studies involving alkyl iodides. Detailed mechanistic studies of the transformation are performed, which are consistent with auto-tandem catalysis involving atom-transfer radical cyclization followed by catalytic
Iron-Catalyzed Tandem Cyclization and Cross-Coupling Reactions of Iodoalkanes and Aryl Grignard Reagents
作者:Jae Gon Kim、Young Hoon Son、Jin Won Seo、Eun Joo Kang
DOI:10.1002/ejoc.201403511
日期:2015.3
Several experimental results, such as cyclopropyl ring opening, the stereochemical outcome of the reaction with a secondary iodide substrate, and intermediate identification with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), support the conclusion that a radical process is involved in this catalytic system. Moreover, deuterium labeling experiments indicated that radical disproportionation could occur in
Cobalt-Catalyzed Tandem Radical Cyclization/C–C Coupling Initiated by Directed C–H Activation
作者:Qiao Sun、Naohiko Yoshikai
DOI:10.1021/acs.orglett.9b01846
日期:2019.7.5
A cobalt–N-heterocyclic carbene catalyst promotes a tandem radical cyclization/C–Ccoupling reaction between tosylamide-tethered bromo-alkenes and aryl N–H imines initiated by chelation-assisted arene C–Hactivation, affording 3-(arylmethyl)pyrrolidine derivatives in moderate to good yields. The reaction tolerates a variety of substituents on the aryl imine as well as various modifications on the bromo-alkene