Photocoupling between Haloheterocyclic Derivatives and Arylalkenes and Arylalkynes: Instruments to Predict Reactivity
摘要:
Parameters useful to predict reactivity and regiochemical control of photocoupling reactions between haloheterocyclic derivatives and arylalkenes or arylalkynes have been studied. Electrochemical properties of arylalkenes and arylalkynes are shown to be useful to predict the reactivity of the substrates. However, oxidation potentials fail as reactivity indices if very fast photochemical processes are in competition with the observed complex formation between substrates and halogen atoms. The regiochemical behavior of the reaction can be estimated on the basis of dipoles of the reagents. In this case the assumptions that a reagent approaches the other on parallel planes and that the prevalent interaction is between the SOMO of the radical and the LUMO of the other reagent have been accepted.
Hydroamination versus Allylic Amination in Iridium-Catalyzed Reactions of Allylic Acetates with Amines: 1,3-Aminoalcohols via Ester-Directed Regioselectivity
作者:Seung Wook Kim、Thomas Wurm、Gilmar A. Brito、Woo-Ok Jung、Jason R. Zbieg、Craig E. Stivala、Michael J. Krische
DOI:10.1021/jacs.8b05683
日期:2018.7.25
In the presence of a neutral dppf-modified iridium catalyst and Cs2CO3, linear allylic acetates react with primary amines to form products of hydroamination with complete 1,3-regioselectivity. The collective data, including deuterium labeling studies, corroborate a catalytic mechanism involving rapid, reversible acetate-directed aminoiridation with inner-sphere/outer-sphere crossover followed by turnover-limiting
Pd-Catalyzed Allylation of Imines to Access α-CF<sub>3</sub>
-Substituted α-Amino Acid Derivatives
作者:Michael Winter、Hyunwoo Kim、Mario Waser
DOI:10.1002/ejoc.201901272
日期:2019.11.14
herein report a high yielding protocol for the direct α‐allylation of easily accessible trifluoropyruvate‐derived imines using Pd‐catalysis. The reaction gives access to a variety of different α‐allylated‐α‐CF3‐amino acids in a straightforward manner, starting from commercially available trifluoropyruvate. We also provide a proof‐of‐concept for an enantioselective protocol (up to er = 75:25) by using
我们在此报告了一种使用 Pd 催化将易于获得的三氟丙酮酸衍生亚胺直接 α-烯丙基化的高产方案。该反应从市售的三氟丙酮酸开始,以直接的方式获得各种不同的 α-烯丙基化-α-CF3-氨基酸。我们还通过使用手性磷烷配体为对映选择性协议(高达 er = 75:25)提供了概念验证。
Pd-Catalyzed Olefination of Furans and Thiophenes with Allyl Esters
作者:Yuexia Zhang、Zejiang Li、Zhong-Quan Liu
DOI:10.1021/ol203013p
日期:2012.1.6
A direct Pd(II)-catalyzed olefination of furans and thiophenes with allyl esters is demonstrated. Under the typical conditions, the dehydrogenative Heck coupling reactions of heteroarenes with allylic esters proceeded via a β-H elimination rather than a β-OAc elimination to give the corresponding γ-substituted allylic esters.
Dual Ni/Organophotoredox Catalyzed Allylative Ring Opening Reaction of Oxabenzonorbornadienes and Analogs
作者:Abdoul G. Diallo、Déborah Paris、Djiby Faye、Sylvain Gaillard、Mark Lautens、Jean-Luc Renaud
DOI:10.1021/acscatal.2c00512
日期:2022.3.18
A general approach for the allylation of oxa- and azabenzonorbornadienes is reported by merging organophotoredox and nickel catalysis. This methodology allowed the diastereoselective allylation of various heterocyclic alkene derivatives with a broader range of allylic acetate compounds compared to previously published procedures. Moreover, no air-sensitive organometallic species and no metal reductants
Stereodivergent Construction of 1,3‐Chiral Centers via Tandem Asymmetric Conjugate Addition and Allylic Substitution Reaction
作者:Jia‐Hao Xie、Yi‐Ming Hou、Zuolijun Feng、Shu‐Li You
DOI:10.1002/anie.202216396
日期:2023.3
cyclohexanones bearing multi-continuous stereocenters by combining copper-catalyzed asymmetric conjugate addition of dialkylzinc reagents to cyclic enones with iridium-catalyzed asymmetric allylicsubstitution reaction. Good to excellent yields, diastereoselectivity and enantioselectivity can be obtained. The current reaction can achieve the stereodivergent construction of nonadjacent stereocenters.