通过碳-碳键的选择性裂解使分子功能化是合成化学中一种很有吸引力的方法。尽管最近在过渡金属催化和自由基化学方面取得了进展,但碳氢化合物原料中惰性 C sp3 -C sp3键的选择性裂解仍然具有挑战性。文献中报道的例子通常涉及含有氧化还原官能团或高度应变分子的底物。在本文中,我们提出了一个用于 C sp3 –C sp3的切割和功能化的简单方案使用光氧化还原催化在烷基苯中键合。我们的方法采用两种不同的断键途径。对于具有叔苄基取代基的底物,普遍采用碳阳离子耦合电子转移机制。对于具有主要或次要苄基取代基的底物,三重单电子氧化级联是适用的。我们的策略提供了一种实用的方法,可以在没有任何杂原子的情况下切割分子中的惰性 C sp3 -C sp3键,从而产生一级、二级、三级和苄基自由基物种。
Ring and carbon-oxygen bond fragmentation as tools for fingerprinting the extent of homolysis during base-catalyzed carbon-carbon bond cleavages of the Haller-Bauer, Cram, and Gilday types
Reductive Activation and Hydrofunctionalization of Olefins by Multiphoton Tandem Photoredox Catalysis
作者:Milena L. Czyz、Mitchell S. Taylor、Tyra H. Horngren、Anastasios Polyzos
DOI:10.1021/acscatal.1c01000
日期:2021.5.7
of olefin feedstocks to architecturally complex alkanes represents an important strategy in the expedient generation of valuable molecules for the chemical and life sciences. Synthetic approaches are reliant on the electrophilicactivation of unactivated olefins, necessitating functionalization with nucleophiles. However, the reductive functionalization of unactivated and less activatedolefins with
A new chiralbisphosphine ligand ((R)-2-diphenylphosphino-2′-diphenylphosphinomethyl-1,1′-binaphthyl) was synthesized from enantiomerically pure (R)-1,1′-binaphthalene-2,2′-diol. Rhodium(I) complexes of this bisphosphine ligand have been used as catalysts for asymmetrichydrogenation of α-alkylstyrenes to give the corresponding aromatic hydrocarbons in up to 77% ee.
Ring and carbon-oxygen bond fragmentation as tools for fingerprinting the extent of homolysis during base-catalyzed carbon-carbon bond cleavages of the Haller-Bauer, Cram, and Gilday types
作者:Leo A. Paquette、George D. Maynard
DOI:10.1021/jo00282a020
日期:1989.10
Photoredox Cleavage of a C<sub>sp3</sub>–C<sub>sp3</sub> Bond in Aromatic Hydrocarbons
Csp3–Csp3 bonds in hydrocarbon feedstocks remains challenging. Examples reported in the literature typically involve substrates containing redox functional groups or highly strained molecules. In this article, we present a straightforward protocol for the cleavage and functionalization of Csp3–Csp3 bonds in alkylbenzenes using photoredox catalysis. Our method employs two distinct bond scission pathways
通过碳-碳键的选择性裂解使分子功能化是合成化学中一种很有吸引力的方法。尽管最近在过渡金属催化和自由基化学方面取得了进展,但碳氢化合物原料中惰性 C sp3 -C sp3键的选择性裂解仍然具有挑战性。文献中报道的例子通常涉及含有氧化还原官能团或高度应变分子的底物。在本文中,我们提出了一个用于 C sp3 –C sp3的切割和功能化的简单方案使用光氧化还原催化在烷基苯中键合。我们的方法采用两种不同的断键途径。对于具有叔苄基取代基的底物,普遍采用碳阳离子耦合电子转移机制。对于具有主要或次要苄基取代基的底物,三重单电子氧化级联是适用的。我们的策略提供了一种实用的方法,可以在没有任何杂原子的情况下切割分子中的惰性 C sp3 -C sp3键,从而产生一级、二级、三级和苄基自由基物种。