Ab initio study of intramolecular ring cyclization of protonated and BF3-coordinated trans- and cis-4,5-epoxyhexan-1-ol
Ab initio study of intramolecular ring cyclization of protonated and BF3-coordinated trans- and cis-4,5-epoxyhexan-1-ol
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DOI：
10.1021/jo990364d
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发表时间：
1999-07-23
影响因子：
3.6
通讯作者：
Thorpe, AJ
中科院分区：
文献类型：
--
作者：
Coxon, JM;Thorpe, AJ
用从头算方法研究了顺式和反式4,5-环氧己烷-1-醇与酸和路易斯酸BF3重排成五元和六元环醚的势能面。表征了HF/6-31G*和B3LYP/6-31G*反应中心构型反转和保留的过渡结构。呋喃的形成优于吡喃是由于在呋喃形成的过渡结构上有更有利的O-C-ep-O键角。与四氢呋喃和四氢吡喃形成相关的扭转O-C-ep-C-ep-O角随结构而变化，与首选途径没有直接关系。
The potential energy surface for the rearrangement of cis- and trans-4,5-epoxyhexan-1-ol with acid and the Lewis acid BF3 to five- and six-membered cyclic ethers has been investigated by ab initio methods. The transition structures involving both inversion and retention of configuration at the reaction center at the HF/6-31G* and B3LYP/6-31G* levels are characterized. The preference for furan formation over pyran is attributed to the more favorable O-C-ep-O bond angles at the transition structures for furan formation. The torsional O-C-ep-C-ep-O angles associated with tetrahydrofuran and tetrahydropyran formation vary with structure and do not directly correlate with the preferred pathway.