作者:Can-Can Bao、Dong-Song Zheng、Xiao Zhang、Shu-Li You
DOI:10.1021/acs.organomet.8b00762
日期:2018.12.24
N-Heterocyclic carbenes (NHCs) were found to be suitable ligands in Ir-catalyzed intermolecular allylic alkylation reaction. In the presence of a catalyst derived from [Ir(dncot)Cl]2 (dncot = dinaphthocyclooctatetraene) and triazolium salt L7, the alkylation products from the reaction of aryl allyl carbonates with sodium dialkyl malonates could be obtained in 85–99% yields favoring the formation of
发现N-杂环卡宾(NHC)是Ir催化的分子间烯丙基烷基化反应中的合适配体。在[Ir(dncot)Cl] 2(dncot =二萘环辛酸酯四烯)和三唑鎓盐L7衍生的催化剂存在下,芳基烯丙基碳酸酯与二烷基丙二酸钠的反应可得到烷基化产物,收率高达85-99%,形成支链产物(90/10→> 99/1 b / l)。此外,手性二氢异喹啉型NHC(DHIQ-NHC)(L8)已成功应用于Ir催化的不对称烯丙基烷基化反应中。对于广泛的底物,获得了优异的对映选择性和中等的区域选择性。
A Bis(Triazolecarboxamido) Ligand for Enantio- and Regioselective Molybdenum-Catalyzed Asymmetric Allylic Alkylation Reactions
作者:Erhan Ozkal、Miquel A. Pericàs
DOI:10.1002/adsc.201300967
日期:2014.3.10
A modular, enantiomerically pure bis(1H‐1,2,3‐triazole‐4‐carboxamide) has been assembled from N,N′‐[(1R,2R)‐cyclohexane‐1,2‐diyl]dipropiolamide through a copper‐catalyzed azide‐alkyne cycloaddition (CuAAC) reaction and evaluated as a ligand in the molybdenum‐catalyzed asymmetricallylicalkylation (MoAAA) reaction, very high regio‐ and enantioselectivities being recorded.
Substituted Pyridylamide Ligands in Microwave-Accelerated Mo(0)-Catalysed Allylic Alkylations
作者:Christina Moberg、Oscar Belda
DOI:10.1055/s-2002-33345
日期:——
bis-pyridylamides were prepared by microwave accelerated nucleophilic substitution of the 4-and 6-halo substituted derivatives of the parent ligand la. The ligands were used in the asymmetric allylation of cinnamyl carbonate catalysed by Mo(0) in which the 4-chloro- and 4-pyrrolidyl substituted ligand derivatives exhibited high regioselectivity (74:1 and 88:1. respectively) and enantioselectivity (96% ee), whereas
methodology for the allylic C–H alkylation of unactivated alkenes with diazocompounds is demonstrated. The developed protocol is able to bypass the possibility of the cyclopropanation of an alkene upon its reaction with the acceptor–acceptor diazocompounds. The protocol is highly accomplished due to its compatibility with various unactivated alkenes functionalized with different sensitive functional groups
Enantioselective Allylic Substitution of Cinnamyl Esters Catalyzed by Iridium−Chiral Aryl Phosphite Complex: Conspicuous Change in the Mechanistic Spectrum by a Countercation and Solvent
作者:Naosumi Kinoshita、Karsten H. Marx、Kiyoshi Tanaka、Kazunori Tsubaki、Takeo Kawabata、Naohiko Yoshikai、Eiichi Nakamura、Kaoru Fuji
DOI:10.1021/jo048834d
日期:2004.11.1
Iridium-catalyzed asymmetric allylic alkylation of monoaryl substrates 4-6 with chiral phosphites 1-3 has been investigated. Although branched isomers were formed with high regioselectivities, the enantioselectivities of these products were remarkably influenced by solvents, countercations, and additives (ZnCl2 and LiCl).