Iron-Catalyzed Isopropylation of Electron-Deficient Aryl and Heteroaryl Chlorides
作者:James N. Sanderson、Andrew P. Dominey、Jonathan M. Percy
DOI:10.1002/adsc.201601097
日期:2017.3.20
of secondaryalkyl‐substituted aryl and heteroaryl chlorides challenge both selectivity and functional group tolerance. This contribution describes the use of statistical design of experiments to develop an effective procedure for the preparation of isopropyl‐substituted (hetero)arenes with minimal isopropyl to n‐propyl isomerization. The reaction tolerates electronically diverse aryl chloride coupling
Mild Negishi Cross-Coupling Reactions Catalyzed by Acenaphthoimidazolylidene Palladium Complexes at Low Catalyst Loadings
作者:Zelong Liu、Ningning Dong、Mizhi Xu、Zheming Sun、Tao Tu
DOI:10.1021/jo400803s
日期:2013.8.2
3a exhibited extremely high catalytic activity toward Negishicross-coupling of alkylzinc reagents with a wide range of (hetero)arylhalides under mild reaction conditions within 30 min. Besides a great number of bromoarenes, various less expensive and inactive (hetero)aryl chlorides were coupled successfully with the alkyl- and arylzincreagents, in which active functional groups (such as -NH2) were
考虑到衍生自π-延伸的咪唑鎓盐的亚烷基的强大的σ-供体性质有利于提高所得钯N-杂环卡宾配合物的催化活性,因此制备了具有健壮的并咪唑-亚烷基钯配合物3a - c,具有不同的大取代基团通过在纯净的3-氯吡啶中与PdCl 2和K 2 CO 3加热,从相应的啶咪唑氯化物中得到满意的收率。即使在催化剂负载量低至0.25 mol%的情况下,配合物3a在温和的反应条件下,在30分钟内显示出对烷基锌试剂与各种(杂)芳基卤化物的Negishi交叉偶联极高的催化活性。除了大量的溴代芳烃外,还成功地将各种较便宜且不活泼的(杂)芳基氯化物与烷基-和芳基锌试剂偶联,其中具有活性官能团(例如-NH 2))即使在无保护的一锅双偶转换中也具有良好的耐受性。此外,在与仲烷基锌试剂偶联的情况下,有效抑制了导致异构化的线性产物的不希望的β-氢化物消除。通过杂芳基锌试剂和杂环氯代芳烃的偶联,该催化剂体系还显示出在杂二芳基结构方面
Ruphos-mediated Suzuki cross-coupling of secondary alkyl trifluoroborates
作者:Adri van den Hoogenband、Jos H.M. Lange、Jan Willem Terpstra、Melle Koch、Gerben M. Visser、Martin Visser、Ties J. Korstanje、Johann T.B.H. Jastrzebski
DOI:10.1016/j.tetlet.2008.04.129
日期:2008.6
A Ruphos-mediated Suzukicross-coupling between (hetero)aryl bromides and secondary alkyltrifluoroborates is described using palladium catalysis. The Ruphos ligand showed superior properties as compared to S-Phos in this type of reaction. This method constitutes a valuable extension to current methods for the straightforward production of secondary-alkylated (hetero)aryl derivatives.
Photochemical generation of aliphatic radicals from benzophenone oxime esters: simple synthesis of alkylbenzenes and alkylpyridines
作者:Masato Hasebe、Takashi Tsuchiya
DOI:10.1016/s0040-4039(00)84763-2
日期:1986.1
aliphatic carboxylic acids and benzophenone oxime, in benzene and pyridine generates various primary, secondary and tertiary aliphatic radicals selectively, and corresponding alkylbenzenes and alkylpyridines are produced in good yields, respectively.
Nickel-Catalyzed Reductive Cross-Coupling of Aryl Bromides with Alkyl Bromides: Et<sub>3</sub>N as the Terminal Reductant
作者:Zhengli Duan、Wu Li、Aiwen Lei
DOI:10.1021/acs.orglett.6b01837
日期:2016.8.19
cross-coupling paradigm using Et3N as the terminal reductant is reported. By using this photoredox catalysis and nickel catalysis approach, a direct Csp2–Csp3 reductive cross-coupling of aryl bromides with alkylbromides is achieved under mild conditions without stoichiometric metal reductants.