Carbene insertion into acyl C-H bonds: Rh(III)-catalyzed cross-coupling of 2-aminobenzaldehydes with conjugated enynones
作者:Yifan Ping、Taiwei Chang、Jianbo Wang
DOI:10.1016/j.tet.2021.132274
日期:2021.7
A rhodium-catalyzed directed acyl C-H bonds carbeneinsertion reaction of 2-aminobenzaldehydes with conjugated enynones has been realized, affording a series of α-furyl ketone derivatives in moderate to good yields with good functional group tolerance. Carbene migratory insertion is proposed as the key step in this transformation.
Csp<sup>3</sup>–P versus Csp<sup>2</sup>–P Bond Formation: Catalyst-Controlled Highly Regioselective Tandem Reaction of Ene-Yne-Ketones with <i>H</i>-Phosphonates
various phosphorylated furans in good yields. A copper carbene generation or a Michael addition is proposed as the key step in the selective construction of the Csp3–P or Csp2–P bond, which is supported by carbene capture reactions and interval 31P NMR experiments. Furthermore, this method features inexpensive metal catalysts, no usage of oxidant, and high atom economy, which make it attractive and practical
在铜催化或碱促进的条件下,各种烯-炔酮与H-膦酸酯反应,以高收率提供各种磷酸化呋喃。卡宾碳捕获反应和间隔31 P NMR实验支持了铜卡宾的生成或迈克尔加成反应作为选择性构建Csp 3 -P或Csp 2 -P键的关键步骤。此外,该方法具有廉价的金属催化剂,不使用氧化剂和高原子经济性的特点,这使其具有吸引力和实用性。
Mechanistic Divergence in the Hydrogenative Synthesis of Furans and Butenolides: Ruthenium Carbenes Formed by
<i>gem</i>
‐Hydrogenation or through Carbophilic Activation of Alkynes
作者:Sebastian Peil、Alois Fürstner
DOI:10.1002/anie.201912161
日期:2019.12.16
Enynes with a tethered carbonyl substituent are converted into substituted furan derivatives upon hydrogenation using [Cp*RuCl]4 as the catalyst. Paradoxically, this transformation can occur along two distinct pathways, each of which proceeds via discrete pianostool ruthenium carbenes. In the first case, hydrogenation and carbene formation are synchronized ("gem-hydrogenation"), whereas the second
Trialkylphosphine-Mediated Synthesis of 2-Acyl Furans from Ynenones
作者:Chao Xu、Stéphane Wittmann、Manuel Gemander、Venla Ruohonen、J. Stephen Clark
DOI:10.1021/acs.orglett.7b01533
日期:2017.7.7
A novel reaction for the synthesis of 2-acyl furans is reported. The reaction is believed to proceed by sequential addition of a trialkylphosphine to an ynenone, 5-exo-dig cyclization to form the furan, and oxidation of the resulting phosphonium ylide with molecular oxygen. Many common functional groups are tolerated during the reaction, and the products are obtained in good to excellent yield under
Synthesis of 2-acylfurans from 3-(1-alkynyl)-2-alken-1-ones via the oxidation of gold–carbene intermediates by H2O2
作者:Tao Wang、Junliang Zhang
DOI:10.1039/c0dt00024h
日期:——
An efficient approach to 2,4,5-trisubstituted 2-acylfurans is described: treating 3-(1-alkynyl)-2-alken-1-ones with AuCl3 in DCM at rt in the presence of H2O2 afforded good yields of 2-acylfurans.