稳定的三环氨基过氧化物可以通过 β,δ'-三酮、H 2 O 2和 NH 基团源(如氨水或铵盐)的无催化剂三组分缩合选择性组装。这个过程是可扩展的并且可以产生克数量的三环杂环,在一个分子中包含过氧化物、氮和氧循环。令人惊讶的是,尽管有多种替代反应路线,通过过氧化物、半缩醛、单过氧缩醛和过氧半缩醛官能团的平衡,这种复杂的三环分子仍然可以选择性地形成!该反应由 H 2 O 2的“立体电子挫折”引发并将热力学和动力学控制元素与在热力学控制条件下演化的各种单环、双环和三环结构相结合,直到它们达到由逆α效应产生的动力学壁,即立体电子罚分过氧碳鎓离子和相关过渡态的形成。在这些条件下,在三个不同的杂环在无环前体框架上组装和融合的阶段,反应在达到最热力学稳定的产物之前停止。
Two-Component versus Three-Component Condensations in the Race between Hydrazide, Triketone, and Hydrogen Peroxide-How do All Six Reactive Centers Cooperate to Incorporate the Most Diverse Set of Heteroatomic Bridges in a Tricyclic Frame?
作者:Ivan A. Yaremenko、Yulia Yu. Belyakova、Peter S. Radulov、Michael G. Medvedev、Nikolai V. Krivoshchapov、Igor V. Alabugin、Alexander O. Terent’ev
DOI:10.1021/acs.joc.3c01415
日期:2023.10.6
frustration drives the acid-catalyzed three-component condensation of β,δ′-triketones with hydrazides and H2O2 to the direction where both nucleophiles and all three electrophilic carbons are involved in the formation of a tricyclic sp3-rich ring system that includes four heteroatoms. The otherwise inaccessible tricyclic N-substituted aminoperoxides are prepared rapidly and selectively from relatively simple
立体电子挫败的缓解将酸催化的 β,δ′-三酮与酰肼和 H 2 O 2的三组分缩合反应向亲核试剂和所有三种亲电子碳均参与形成富含 sp 3的三环的方向进行。包含四个杂原子的环系统。原本难以获得的三环N-取代氨基过氧化物可以从相对简单的底物中快速、选择性地制备,产率良好至高。
Preparation of a microsized cerium chloride-based catalyst and its application in the Michael addition of β-diketones to vinyl ketones
作者:Alexander O. Terent'ev、Vera A. Vil'、Ivan A. Yaremenko、Oleg V. Bityukov、Dmitri O. Levitsky、Vladimir V. Chernyshev、Gennady I. Nikishin、Fabrice Fleury
DOI:10.1039/c3nj01454a
日期:——
evaporation of its alcoholic solutions. The way of the preparation of the cerium chloride-based catalyst plays a decisive role in its catalytic activity. This catalyst is efficient in the Michaeladdition of β-diketones to vinyl ketones giving β,δ-triketones.
Inverse α-Effect as the Ariadne’s Thread on the Way to Tricyclic Aminoperoxides: Avoiding Thermodynamic Traps in the Labyrinth of Possibilities
作者:Ivan A. Yaremenko、Yulia Yu. Belyakova、Peter S. Radulov、Roman A. Novikov、Michael G. Medvedev、Nikolai V. Krivoshchapov、Alexander A. Korlyukov、Igor V. Alabugin、Alexander O. Terent′ev
DOI:10.1021/jacs.2c00406
日期:2022.4.27
thermodynamic and kinetic control with a variety of mono-, bi-, and tricyclic structures evolving under the conditions of thermodynamic control until they reach a kinetic wall created by the inverse α-effect, that is, the stereoelectronic penalty for the formation of peroxycarbenium ions and related transition states. Under these conditions, the reaction stops before reaching the most thermodynamically
稳定的三环氨基过氧化物可以通过 β,δ'-三酮、H 2 O 2和 NH 基团源(如氨水或铵盐)的无催化剂三组分缩合选择性组装。这个过程是可扩展的并且可以产生克数量的三环杂环,在一个分子中包含过氧化物、氮和氧循环。令人惊讶的是,尽管有多种替代反应路线,通过过氧化物、半缩醛、单过氧缩醛和过氧半缩醛官能团的平衡,这种复杂的三环分子仍然可以选择性地形成!该反应由 H 2 O 2的“立体电子挫折”引发并将热力学和动力学控制元素与在热力学控制条件下演化的各种单环、双环和三环结构相结合,直到它们达到由逆α效应产生的动力学壁,即立体电子罚分过氧碳鎓离子和相关过渡态的形成。在这些条件下,在三个不同的杂环在无环前体框架上组装和融合的阶段,反应在达到最热力学稳定的产物之前停止。