Decarbonylative C–H Coupling of Azoles and Aryl Esters: Unprecedented Nickel Catalysis and Application to the Synthesis of Muscoride A
摘要:
A nickel-catalyzed decarbonylative C-H biaryl coupling of azoles and aryl esters is described. The newly developed catalytic system does not require the use of expensive metal catalysts or silver- or copper-based stoichiometric oxidants. We have successfully applied this new C-H arylation reaction to a convergent formal synthesis of muscoride A.
Synthesis of Substituted Oxazoles by Visible-Light Photocatalysis
作者:Tanmay Chatterjee、Ji Young Cho、Eun Jin Cho
DOI:10.1021/acs.joc.6b00989
日期:2016.8.19
A simple and practical method for the synthesis of substituted oxazoles has been developed using readily available α-bromoketones and benzylamines by visible-light photocatalysis at room temperature. The process, which requires 1 mol % of [Ru(bpy)3]Cl2 photocatalyst with K3PO4 and CCl3Br, is effective for accessing a variety of valuable oxazole compounds. The synthetic utility of our protocol was also
已经开发了一种简单而实用的合成取代的恶唑的方法,该方法使用易得的α-溴代酮和苄胺,在室温下通过可见光光催化进行合成。该方法需要1摩尔%的具有K 3 PO 4和CCl 3 Br的[Ru(bpy)3 ] Cl 2光催化剂,可有效地获得各种有价值的恶唑化合物。我们的协议的合成效用也通过制备天然产物texaline得到了证明。
C-H Bond Activation: A Versatile Protocol for the Direct Arylation and Alkenylation of Oxazoles
The versatile palladium complex Pd(PPh3)4 catalyses both direct arylation and alkenylation of oxazoles efficiently. The method is regioselective and stereospecific with respect to bromoalkenes and tolerates a wide range of functional groups.
Nickel-Catalyzed Coupling of Azoles with Aromatic Nitriles
作者:Mckenna G. Hanson、Noelle M. Olson、Zubaoyi Yi、Grace Wilson、Dipannita Kalyani
DOI:10.1021/acs.orglett.7b01938
日期:2017.8.18
This manuscript describes the Ni-catalyzed coupling of azoles with aromaticnitriles. The use of BPh3 promotes these arylations with electronically diverse azoles and benzonitriles. While the nickel catalyst is necessary for the arylations of phenyl oxazoles, arylation of benzoxazoles with some nitriles affords the arylated products even in the absence of the Ni catalyst albeit in lower yield than
Iodine catalyzed synthesis of 2,5-substituted oxazoles from N-arylethylamides through intramolecular C(sp3)–H functionalization under metal-free conditions is described.