Highly Strained 2,3-Bridged 2H-Azirines at the Borderline of Closed-Shell Molecules

被引：13

作者：

Banert, Klaus ^{[1
]}

Meier, Barbara ^{[1
]}

Penk, Enrico ^{[1
]}

Saha, Biswajit ^{[1
]}

Wuerthwein, Ernst-Ulrich ^{[2
]}

Grimme, Stefan ^{[2
]}

Rueffer, Tobias ^{[1
]}

Schaarschmidt, Dieter ^{[1
]}

Lang, Heinrich ^{[1
]}

机构：

[1] Tech Univ Chemnitz, D-09111 Chemnitz, Germany

[2] Univ Munster, Inst Organ Chem, D-48149 Munster, Germany

来源：

CHEMISTRY-A EUROPEAN JOURNAL | 2011年 / 17卷 / 04期

关键词：

azides; nitrogen heterocycles; photolysis; quantum chemical calculations; reactive intermediates; TRIPLET ALKYL NITRENES; ALPHA-AZIDOACETOPHENONES; PHOTOLYSIS; REARRANGEMENT; THERMOLYSIS; AZIRINES; DIAZOMETHANE; DERIVATIVES; AZIRIDINES; CLEAVAGE;

D O I：

10.1002/chem.201002474

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Substituted 1-azidocyclopentenes and 1-azidocyclohexenes were photolyzed to generate 2,3-bridged 2H-azirines. In the case of bridgehead azirines with a six-membered carbocycle, detection by NMR spectroscopic analysis was possible, whereas even kinetically stabilized bridgehead azirines with a five-membered ring could not be characterized by low-temperature NMR spectroscopic analysis. Thus, a recent report on the latter heterocycles was corrected. Depending on the substitution pattern, irradiation of 1-azido-cyclopentenes either led to products that can be explained on the basis of short-lived 2,3-bridged 2H-azirines, or gave secondary products generated from triplet nitrenes. The diverse photoreactivity of 2,3-bridged 2H-azirines was also studied by quantum chemical methods (DFT, CCSD(T), CASSCF(6,6)) with respect to the singlet and triplet energy surfaces. The ring-opening processes leading to the corresponding vinyl nitrenes were identified as key steps for the observed reactivity.

引用

页码：1128 / 1136

页数：9

共 60 条

[1] On the mechanism of the reaction of organic azides with transition metals: Evidence for triplet nitrene capture [J].