近年来,光催化剂的不断发展,以满足对光氧化还原催化中光物理和氧化还原性能日益增长的需求,设计了复杂的结构或替代策略来获得高度还原或氧化系统。我们在此报告了使用peri- xanthenoxanthene (PXX),一种简单且廉价的染料,作为一种有效的光催化剂。其高度还原的激发态可激活多种底物,从而引发有用的自由基反应。最初证明了基准转换,例如通过有机卤化物的光还原产生的有机自由基添加到自由基陷阱。还显示可以使用更复杂的双催化歧管:β当使用仲胺作为有机催化剂时,环酮的芳基化是成功的,而当使用 Ni 助催化剂时,芳基卤化物与胺和硫醇的交叉偶联反应是成功的。昂贵的氟-四氢-1 H-吡啶并[4,3- b ]吲哚的高效两步合成应用也已得到证实,该吲哚是研究药物塞替吡仑的关键合成中间体。
Regioselective ketone α-alkylation with simple olefins via dual activation
作者:Fanyang Mo、Guangbin Dong
DOI:10.1126/science.1254465
日期:2014.7.4
C-H bonds of ketones. Traditional methods to form such products rely on the preliminary reaction of the ketone with a base, followed by subsequent reaction with an alkyl halide. The authors used a ligand that simultaneously activates the ketone and guides the catalytic rhodium to the right location. This approach removes the need for the other reagents and eliminates the associated halide salt byproducts
Catalytic activation of carbon–carbon bonds in cyclopentanones
作者:Ying Xia、Gang Lu、Peng Liu、Guangbin Dong
DOI:10.1038/nature19849
日期:2016.11
we report a general approach to the catalytic activation of C–C bonds in simple cyclopentanones and some cyclohexanones. The key to our success is the combination of a rhodium pre-catalyst, an N-heterocyclic carbene ligand and an amino-pyridine co-catalyst. When an aryl group is present in the C3 position of cyclopentanone, the less strained C–C bond can be activated; this is followed by activation of
<i>peri</i>
‐Xanthenoxanthene (PXX): a Versatile Organic Photocatalyst in Organic Synthesis
作者:Cristofer Pezzetta、Andrea Folli、Oliwia Matuszewska、Damien Murphy、Robert W. M. Davidson、Davide Bonifazi
DOI:10.1002/adsc.202100030
日期:2021.10.19
to be accessible: the β-arylation of cyclic ketones is successful when using a secondary amine as organocatalyst, while cross-coupling reactions of aryl halides with amines and thiols are obtained when using a Ni co-catalyst. Application to the efficient two-step synthesis of the expensive fluoro-tetrahydro-1H-pyrido[4,3-b]indole, a crucial synthetic intermediate for the investigational drug setipiprant
近年来,光催化剂的不断发展,以满足对光氧化还原催化中光物理和氧化还原性能日益增长的需求,设计了复杂的结构或替代策略来获得高度还原或氧化系统。我们在此报告了使用peri- xanthenoxanthene (PXX),一种简单且廉价的染料,作为一种有效的光催化剂。其高度还原的激发态可激活多种底物,从而引发有用的自由基反应。最初证明了基准转换,例如通过有机卤化物的光还原产生的有机自由基添加到自由基陷阱。还显示可以使用更复杂的双催化歧管:β当使用仲胺作为有机催化剂时,环酮的芳基化是成功的,而当使用 Ni 助催化剂时,芳基卤化物与胺和硫醇的交叉偶联反应是成功的。昂贵的氟-四氢-1 H-吡啶并[4,3- b ]吲哚的高效两步合成应用也已得到证实,该吲哚是研究药物塞替吡仑的关键合成中间体。
Copper Catalyzed Conjugate Addition of Highly Functionalized Arylmagnesium Compounds to Enones
Highly functionalized arylmagnesium bromides are readily prepared by an iodine–magnesium exchange reaction. In the presence of catalytic amounts of copper(I) salts and chlorotrimethylsilane, they add to various enones leading to the conjugateaddition products in 66–89% yield.
PHENYL-CYCLOALKYL AND PHENYL-HETEROCYCLIC DERIVATIVES AS S1P RECEPTOR AGONISTS
申请人:Lynch Kevin R.
公开号:US20090105315A1
公开(公告)日:2009-04-23
Compounds that have agonist activity at one or more of the S1P receptors are provided. The compounds are sphingosine analogs that, after phosphorylation, can behave as agonists at S1P receptors.