Enantioselective Diarylcarbene Insertion into Si–H Bonds Induced by Electronic Properties of the Carbenes
作者:Liang-Liang Yang、Declan Evans、Bin Xu、Wen-Tao Li、Mao-Lin Li、Shou-Fei Zhu、K. N. Houk、Qi-Lin Zhou
DOI:10.1021/jacs.0c04725
日期:2020.7.15
enantioselection usually depends on differences in steric interactions between prochiral substrates and a chiral catalyst. We have discovered a carbene Si-H insertion in which the enantioselectivity depends primarily on the electronic characteristics of the carbene substrate, and the log(er) values are linearly related to Hammett parameters. A new class of chiral tetraphosphate dirhodium catalysts was developed
The first ruthenium-catalyzed umpolung carboxylation of hydrazones with CO2 to generate important aryl acetic acids is reported. Besides aldehyde hydrazones, a variety of ketone hydrazones, which have not been successfully applied in previous umpolung reactions with other reactive electrophiles, also show high reactivity and selectivity under mild conditions. Moreover, this operationally simple protocol
报道了第一次钌催化腙与 CO 2的 umpolung 羧化生成重要的芳基乙酸。除醛腙外,多种酮腙在与其他反应性亲电试剂的超微球反应中尚未成功应用,在温和条件下也表现出高反应性和选择性。此外,这种操作简单的协议具有良好的官能团耐受性,易于扩展,并提供了重要结构的简单推导,包括生物活性联苯乙酸和阿地芬。计算研究表明,这种 umpolung 反应通过生成 Ru-nitrenoid 然后与 CO 2协同 [4 + 2] 环加成反应进行。
Reimlinger,H., Chemische Berichte, 1964, vol. 97, p. 3493 - 3502
作者:Reimlinger,H.
DOI:——
日期:——
Triplet-triplet fluorescence and spin polarization of 1- and 2-naphthylphenylcarbenes
作者:Alain. Despres、Eva. Migirdicyan、Karl. Haider、Vincent M. Maloney、Matthew S. Platz