Scope of the Thermal Ring-Expansion Reaction of Boroles with Organoazides

被引：48

作者：

Braunschweig, Holger ^{[1
,2
]}

Celik, Mehmet Ali ^{[1
,2
]}

Dellermann, Theresa ^{[1
,2
]}

Frenking, Gernot ^{[3
,4
]}

Hammond, Kai ^{[1
,2
]}

Hupp, Florian ^{[1
,2
]}

Kelch, Hauke ^{[1
,2
]}

Krummenacher, Ivo ^{[1
,2
]}

Lindl, Felix ^{[1
,2
]}

Mailaender, Lisa ^{[1
,2
]}

Muessig, Jonas H. ^{[1
,2
]}

Ruppert, Annika ^{[1
,2
]}

机构：

[1] Julius Maximilians Univ Wurzburg, Inst Anorgan Chem, D-97074 Wurzburg, Germany

[2] Julius Maximilians Univ Wurzburg, Inst Sustainable Chem & Catalysis Boron, D-97074 Wurzburg, Germany

[3] Philipps Univ Marburg, Fachbereich Chem, Hans Meerwein Str, D-35043 Marburg, Germany

[4] DIPC, PK 1072, Donostia San Sebastian 20080, Euskadi, Spain

来源：

CHEMISTRY-A EUROPEAN JOURNAL | 2017年 / 23卷 / 33期

关键词：

azaborinines; azides; boron; heterocycles; ring expansion; PI INTERACTIONS; BN ISOSTERES; T4; LYSOZYME; C-C; 1,2-AZABORININES; ANTIAROMATICITY; BENZENE; ANALOGS; CAVITY; AZIDES;

D O I：

10.1002/chem.201700749

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Electronic and steric factors have been investigated in the thermal ring expansion of boroles with organic azides, a reaction that provides access to highly arylated 1,2-azaborinines, BN analogues of benzene. Reactions of a variety of boroles and organic azides demonstrate that the synthetic method is quite general in furnishing 1,2-azaborinines, but the respective reaction rates reveal a strong dependence on the substituents on the two reactants. The products have been characterized by UV/Vis, electrochemical, NMR, and Xray diffraction methods, clarifying their constitutions and highlighting substituent effects on the electronic structure of the 1,2-azaborinines. Furthermore, analysis of several possible mechanistic pathways for 1,2-azaborinine formation, as studied by DFT, revealed that a two-step mechanism involving azide-borole adduct formation and nitrene insertion is favored.

引用

页码：8006 / 8013

页数：8

共 46 条

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