Selective C‐alkylation Between Alcohols Catalyzed by N‐Heterocyclic Carbene Molybdenum
作者:Jiahao Liu、Weikang Li、Yinwu Li、Yan Liu、Zhuofeng Ke
DOI:10.1002/asia.202100959
日期:2021.10.18
The first molybdenum-catalyzed C-alkylation between alcohols via borrowing hydrogen is reported.
报道了第一个钼催化的醇之间通过借氢进行的 C-烷基化反应。
Nickel-Catalyzed Guerbet Type Reaction: C-Alkylation of Secondary Alcohols <i>via</i> Double (de)Hydrogenation
作者:Reshma Babu、Murugan Subaramanian、Siba P. Midya、Ekambaram Balaraman
DOI:10.1021/acs.orglett.1c00782
日期:2021.5.7
Acceptorless double dehydrogenativecross-coupling of secondary and primaryalcohols under nickel catalysis is reported. This Guerbet type reaction provides an atom- and a step-economical method for the C-alkylation of secondaryalcohols under mild, benign conditions. A broad range of substrates including aromatic, cyclic, acyclic, and aliphatic alcohols was well tolerated. Interestingly, the C-alkylation
Surmounting Alkoxide Trap Strategy: <i>N</i>-Heterocyclic Carbene Chromium(0)-Catalyzed <i>C</i>-Alkylation between Alcohols
作者:Peifeng Su、Zhe Chen、Jinyu Ni、Zhenjie Yang、Yinwu Li、Zhuofeng Ke
DOI:10.1021/acscatal.3c03440
日期:2023.10.6
the key metal-alkoxide intermediate, thus overcoming the thermodynamic sink due to the alkoxide trap problem. It is plausible that the Cr(III) systems need to be reduced to Cr(II) for weakening the alkoxide trap effect and enhancing activity by using reductive strong bases. This surmounting alkoxide trap strategy should be helpful for the development of efficient and nonprecious transition metal catalysts
A simple base, KOH-catalyzed cross-coupling of primary and secondaryalcohols is reported in which the primaryalcohols play the role of alkylation reagents. EPR and mechanistic studies confirmed the involvement of radical and ketone intermediates formed from primary and secondaryalcohols, respectively, leading to the formation of β-alkylated secondaryalcohols. Graphical abstract A simple base-catalyzed
Not borrowed: A new method was developed for the cross‐coupling of two different alcohols (see scheme). This carbon–carbonbondformation was realized by using a small amount of CuBr (0.05–0.2 mol %) and NaOH (4–20 mol %) in the presence of H2 (1 atm), and provides an alternative procedure for longer‐chain alcohols. The catalytic cycle was different from those reported to date for the Guerbet reaction