有机化学 ›› 2021, Vol. 41 ›› Issue (11): 4327-4337.DOI: 10.6023/cjoc202106038 上一篇    下一篇

研究论文

银催化的硅烷氧基炔和羰基化合物的[2+2]环加成机理:硅正离子迁移主导的过程

王恒定a,b, 江凌a,b, 梁鸿雁c, 樊红军a,b,*()   

  1. a 中国科学院大连化学物理研究所 分子反应动力学国家重点实验室 辽宁大连 116023
    b 中国科学院大学 北京 100864
    c 西宁特钢技术中心 西宁 810005
  • 收稿日期:2021-06-22 修回日期:2021-08-04 发布日期:2021-08-24
  • 通讯作者: 樊红军
  • 基金资助:
    国家重点研发计划(2016YFB0600301); 国家自然科学基金(92061114); 国家自然科学基金(21873096); 中科院战略先导计划(XDB17010200)

Mechanism of Silver-Catalyzed [2+2] Cycloaddition between Siloxy-Alkynes and Carbonyl Compound: A Silylium Ion Migration Approach

Hengding Wanga,b, Ling Jianga,b, Hongyan Liangc, Hongjun Fana,b()   

  1. a State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023
    b University of Chinese Academy of Sciences, Beijing 100864
    c Technical Center, Xining Special Steel Co Ltd., Xining 810005
  • Received:2021-06-22 Revised:2021-08-04 Published:2021-08-24
  • Contact: Hongjun Fan
  • Supported by:
    National Key Research and Development Program of China(2016YFB0600301); National Natural Science Foundation of China(92061114); National Natural Science Foundation of China(21873096); Strategic Priority Research Program of Chinese Academy of Sciences(XDB17010200)

银离子可以高效地催化硅烷氧基炔与α,β-不饱和羰基化合物之间的[2+2]环加成反应, 在银离子催化下硅烷氧基炔可以与甲醛的羰基发生[2+2]环加成后开环生成不饱和酯. 利用密度泛函理论(DFT)计算发现, 在这两个反应中银离子与硅烷氧基炔之间相互作用, 将硅烷氧基炔激活成为硅正离子和银烯酮, 硅正离子进一步催化羰基化合物(α,β-不饱和羰基化合物或者醛)和银烯酮之间的[2+2]环加成反应.

关键词: 硅正离子, [2+2]环加成, 银烯酮, 醛的烯化, 硅烷氧基炔

Mechanism of silver-catalyzed [2+2] cycloaddition between siloxy-alkynes and α,β-unsaturated carbonyl compound remains controversial. Based on density functional theory (DFT) calculation, it is revealed that Ag+ activate siloxy-alkyne into silver-ketene and silylium ion (TIPS+) in this reaction. TIPS+ then promote [2+2] cycloaddition between α,β-unsaturated carbonyl compound and silver-ketene to form cyclobutane-intermediate, which undergos TIPS+ migration and transforms into final product. The mechanism of Ag+ catalyzed olefination of aldehydes using siloxy-alkynes was also investigated, the results showed that TIPS+ migration also took place in this reaction. In the two reactions studied, Ag+ interacts with π-bond of siloxy-alkynes and triggers TIPS+ migration, which offers alternative solution to silylium-catalyzed reaction. As similarity of ynolates, silver-ketenes are more stable, which can undergo 1,4-nucleophilic addition with α,β- unsaturated compound. For [2+2] cycloaddition, catalytic variant is rather limited, this work provides a different perspective to obtain four-membered ring products or its ring-open derivates.

Key words: silylium ion, [2+2] cycloaddition, silver-ketene, olefination of aldehyde, siloxy-alkyne