Mechanism of methane activation by electrophiles generated in the AlBr5 system:: an MNDO/PM3 study of the potential energy surface of the [AlBr5 + CH4] system

被引：4

作者：

Chistyakov, AL ^{[1
]}

Stankevich, IV ^{[1
]}

Gambaryan, NP ^{[1
]}

Akhrem, IS ^{[1
]}

机构：

[1] Russian Acad Sci, AN Nesmeyanov Organoelement Cpds Inst, Moscow 117813, Russia

来源：

RUSSIAN CHEMICAL BULLETIN | 2000年 / 49卷 / 05期

关键词：

methane; bromine; aluminum bromide; complexes Br-2 center dot AlBr3; superelectrophiles; mechanism of electrophilic activation of alkanes; quantum-chemical calculations; MNDO/PM3; method; potential energy surface;

D O I：

10.1007/BF02494699

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Fragments of the potential energy surfaces (PES) of the AlBr5 (I) and [AlBr5 + CH4] (II) systems were studied by the MNDO/PM3 method. Five local minima corresponding to Br-2 . AlBr3 donor-acceptor complexes were found on the PES of system I. Two of these complexes have a pronounced ionic character. In system II, among the products of barrierless addition of Br-2 . AlBr3 complexes to CH4, the methane molecule is activated only in two complexes. These are products of the attack of the most electrophilic AlBr5 complexes on a H atom of the methane molecule. The potential barriers to conversion of these products into complexes with structures formally corresponding to the products of the attack of electrophiles on a C-H bond (the Olah scheme) or the C atom of methane molecule (the Schreiner scheme) were calculated.

引用

页码：799 / 805

页数：7

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