Cobalt-Catalyzed Direct Alkenylation of 2-Methylquinolines with Aldehydes via C(sp3)–H Functionalization in Water
摘要:
The direct C(sp(3))-H alkenylation of 2-methylquinolines with aldehydes as a simple methodology to afford 2-alkenylated quinolines is reported. In the presence of catalytic CoCl2 in water, the economically and ecologically sound transformation is proposed to proceed via the direct benzylic addition to the aldehyde followed by an elimination step to provide 2-alkenylated quinolines in good to excellent yield of up to 95%.
Catalytic Asymmetric SiO Coupling of Simple Achiral Silanes and Chiral Donor-Functionalized Alcohols
作者:Andreas Weickgenannt、Marius Mewald、Thomas W. T. Muesmann、Martin Oestreich
DOI:10.1002/anie.200905561
日期:2010.3.15
Silicon alley: SiH and HOR are enantioselectively coupled in the presence of a chiral CuH complex. In this way, the kinetic resolution of racemic mixtures of alcohols is accomplished through asymmetric protection with standard silanes (see scheme; R=aryl or alkyl, Ar=3,5‐xylyl, Np=2‐naphthyl; s=selectivity factor).
硅胡同:硅 H和H 或者,对映选择性地耦合在手性铜的存在 H络合物。通过这种方式,醇的外消旋混合物的动力学拆分可通过使用标准硅烷进行不对称保护来实现(参见方案; R =芳基或烷基,Ar = 3,5-二甲苯基,Np = 2-萘基; s =选择性因子)。
Stereoselective Alcohol Silylation by Dehydrogenative Si-O Coupling: Scope, Limitations, and Mechanism of the Cu-H-Catalyzed Non-Enzymatic Kinetic Resolution with Silicon-Stereogenic Silanes
silanes-a process that was found to proceed without racemization at the siliconatom if asymmetrically substituted. The present investigation starts from this pivotal observation since silicon-stereogenic silanes are thereby suitable for the reagent-controlled kinetic resolution of racemic alcohols, in which asymmetry at the siliconatom enables discrimination of enantiomeric alcohols. In this full account
Highly efficient asymmetric bioreduction of 1-aryl-2-(azaaryl)ethanones. Chemoenzymatic synthesis of lanicemine
作者:Ramón Liz、Elisa Liardo、Francisca Rebolledo
DOI:10.1039/c9ob01616c
日期:——
1-Aryl-2-(azaaryl)ethanols with ee > 99% have been prepared by KRED-catalyzed reduction of the ketone precursors. A chemoenzymatic synthesis of lanicemine is described.
Highly Enantioselective Iridium-Catalyzed Hydrogenation of 2-Benzylquinolines and 2-Functionalized and 2,3-Disubstituted Quinolines
作者:Da-Wei Wang、Xiao-Bing Wang、Duo-Sheng Wang、Sheng-Mei Lu、Yong-Gui Zhou、Yu-Xue Li
DOI:10.1021/jo900073z
日期:2009.4.3
The enantioselectivehydrogenation of 2-benzylquinolines and 2-functionalized and 2,3-disubstituted quinolines was developed by using the [Ir(COD)Cl]2/bisphosphine/I2 system with up to 96% ee. Moreover, mechanistic studies revealed the hydrogenation mechanism of quinoline involves a 1,4-hydride addition, isomerization, and 1,2-hydride addition, and the catalytic active species may be a Ir(III) complex
通过使用[Ir(COD)Cl] 2 /双膦/ I 2体系(ee高达96%)开发了2-苄基喹啉和2-官能化和2,3-二取代喹啉的对映选择性氢化。而且,机理研究表明,喹啉的氢化机理涉及1,4-氢化物的加成,异构化和1,2-氢化物的加成,并且催化活性物质可以是与氯化物和碘化物的Ir(III)络合物。
AN ALDOL-TYPE REACTION OF ACTIVE METHYL GROUPS OF NITROGEN-CONTAINING HETEROAROMATIC COMPOUNDS
作者:Hiroshi Hamana、Tsutomu Sugasawa
DOI:10.1246/cl.1983.333
日期:1983.3.5
Active methyl groups of nitrogen-containing heteroaromatic compounds react with benzaldehydes in the presence of 9-BBN triflate and diisopropylethylamine in dichloromethane to give the corresponding aldol-type products under mild conditions.