三取代烯烃的立体选择性合成是有机化学中长期存在的挑战,因为三取代烯烃的 E 和 Z 异构体之间的能量差异很小(与 1,2-二取代烯烃相比)。1,1-二取代烯烃的过渡金属催化异构化可以作为三取代烯烃的替代方法,但由于与反应效率和立体选择性有关的问题,它仍然不发达。在这里,我们展示了一种新型钴催化剂可以克服这些挑战,为获得广泛的三取代烯烃提供有效和立体选择性的途径。该协议与单烯和二烯兼容,并表现出良好的官能团耐受性和可扩展性。而且,它已被证明是构建有机发光体和氘代三取代烯烃的有用工具。对该机制的初步研究表明,该反应涉及钴氢化物途径。该反应的高立体选择性归因于 π-π 堆积效应和底物和催化剂之间的空间位阻。
三取代烯烃的立体选择性合成是有机化学中长期存在的挑战,因为三取代烯烃的 E 和 Z 异构体之间的能量差异很小(与 1,2-二取代烯烃相比)。1,1-二取代烯烃的过渡金属催化异构化可以作为三取代烯烃的替代方法,但由于与反应效率和立体选择性有关的问题,它仍然不发达。在这里,我们展示了一种新型钴催化剂可以克服这些挑战,为获得广泛的三取代烯烃提供有效和立体选择性的途径。该协议与单烯和二烯兼容,并表现出良好的官能团耐受性和可扩展性。而且,它已被证明是构建有机发光体和氘代三取代烯烃的有用工具。对该机制的初步研究表明,该反应涉及钴氢化物途径。该反应的高立体选择性归因于 π-π 堆积效应和底物和催化剂之间的空间位阻。
Direct Synthesis of Aryl Ketones by Palladium-Catalyzed Desulfinative Addition of Sodium Sulfinates to Nitriles
作者:Jing Liu、Xianya Zhou、Honghua Rao、Fuhong Xiao、Chao-Jun Li、Guo-Jun Deng
DOI:10.1002/chem.201101252
日期:2011.7.11
efficient method for the synthesis of various aryl ketones by palladium‐catalyzed desulfinative addition of aromatic sulfinic acid sodiumsalts to various nitriles is described (see scheme). Aromatic and aliphatic nitriles are successfully reacted with arenesulfinic acid sodiumsalts to form aryl ketones in good yields.
Rhodium-catalysed synthesis of fused pyrimidine derivatives employing N-sulfonyl-1,2,3-triazoles as a 1-aza-[4C] synthon
作者:Ze-Feng Xu、Yuehui An、Yidian Chen、Shengguo Duan
DOI:10.1016/j.tetlet.2019.06.023
日期:2019.7
A new synthetic application of N-sulfonyl-1,2,3-triazoles acting as a 1-aza-[4C] synthon via the 1,2-shift reaction of an α-imine rhodium carbene was developed for the synthesis of fused pyrimidine derivatives. The high reactivity of the strained three-membered 2H-azirine ring facilitated the unusual cyclization of electron-deficient dienes with electron-deficient dienophiles. The compatibility was
Electrochemical oxidation synergizing with Brønsted-acid catalysis leads to [4 + 2] annulation for the synthesis of pyrazines
作者:Kun Liu、Chunlan Song、Jiarong Wu、Yuqi Deng、Shan Tang、Aiwen Lei
DOI:10.1039/c8gc03786h
日期:——
Electrochemical oxidative [4 + 2] annulation for the synthesis of pyrazines.
电化学氧化[4 + 2]环化合成吡嗪。
Catalytic Reductive Cross‐Coupling between Aromatic Aldehydes and Arylnitriles
作者:Atsuhisa Mitsui、Kazunori Nagao、Hirohisa Ohmiya
DOI:10.1002/chem.202100763
日期:2021.4.26
A reductive cross‐coupling reaction between aromatic aldehydes and arylnitriles using a copper catalyst and a silylboronate as a reductant is reported. This protocol represents an unprecedented approach to the chemoselective synthesis of α‐hydroxy ketones by electrophile–electrophile cross‐coupling.
A formal [3 + 2]-cycloaddition reaction of 2H-azirines with nitrosoarenes has been achieved under irradiation by visible light with the assistance of organic dye photoredox catalyst. This method utilizes nitrosoarenes as efficient radical acceptors and provides a green and powerful method for a series of biologically important 1,2,4-oxadiazole derivatives in moderate to good yields.