A New Type of Nonbenzenoid Aromatic Carbocation : 1, 6-Methano[10]AnnulenylCation.

一种新型非苯环芳香族碳正离子：1, 6-甲醇[10]环烯基阳离子。

基本信息

批准号：
02804041
负责人：
SONODA Takaaki
金额：
$ 1.15万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1991
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02804041/
关键词：
Reactive intermediate Nonbenzenoid aromatic compound Carbocation Quantum chemical calulations

项目摘要

The structure-reactivity relatioship of a new type of nonbenzenoid aromatic carbocation with a positive charge on an unsaturated carbon atom, 1, 6-methano[10]annulen-2-yl cation, was investigated by theoretical and experimental methods.a. A comparison of experimental results in solvolysis with theoretical calculations by semiempirical MO methods with respect to the structure-stability relationship of carbocations with a positive charge on an unsaturated canbon atom indicated that the carbocation 30 kcal/mol more stable than phenyl cation can be generated in the S_N1 solvolysis of the corresponding triflate precursors.b. Incontrast to planar 1-naphthyl cation, 1, 6-methano[10]annulen-2-yl cation is highly stabilized by the delocalization of the positive charge on C-2 atom into 10 pi electron system because of its nonplanar structure and the contribution of a limiting allene structure.c. 1, 6-Methano[10]annulen-2-ylcation was generated in gas phase from the corresponding annulenyl bromide derivative.d. The solvolysis of the annulenyl triflate in trifluoroethanol (TFE) gave complex mixtures containing some products by triflate substitution with TFE solvent.e. An experiment of quantitative dideuterio substitution of the 2, 7-dibromoannulene derivative indicated a possibility of the generation of the annulenyl cation in the beta-decay decomposition of the corresponding 2, 7-ditritioannulene derivative in gas phase and solution phase.

通过理论和实验方法研究了一种新型的非苯苯二酚芳香族碳酸盐型和阳性电荷的新型非苯苯二酚芳香族碳分配，1，6-Methano [10] Annulen-2-基阳离子。通过半经验MO方法与理论计算进行实验结果的比较，与在不饱和碳原子上具有阳性电荷的碳碳的结构稳定性关系表明，在相应的三酸酯先例的S_N1溶解中，比苯基阳离子比苯基阳离子更稳定30 kcal/mol稳定。与平面1-萘基阳离子，1，6-甲氧烷[10] Annulen-2-yl阳离子的对立相反，由于其非平面结构和有限的Allene结构的贡献，C-2原子上的正电荷在10 PI电子系统中高度稳定。 1，6-甲氧[10] Annulen-2-囊是从相应的环烯基溴衍生物中的气相产生的。三氟乙醇（TFE）中三烯基三叶酸酯的溶解分解产生了复杂的混合物，其中包含一些用TFE溶剂替代的产物的混合物。e。 2，7二溴氨基烯衍生物的定量dideutio取代的实验表明，在相应的2个，7-二硝基硝基衍生物在气相和溶液相中的β-末期分解中产生环烯基阳离子的可能性。