<sup>13</sup>C NMR/DFT/GIAO Studies of Phenylene Bis(1,3-dioxolanium) Dications and 2,4,6-Triphenylene Tris(1,3-dioxolanium) Trication
作者:V. Prakash Reddy、Golam Rasul、G. K. Surya Prakash、George A. Olah
DOI:10.1021/jo020753z
日期:2003.5.1
The o-, m-, and p-phenylene bis(1,3-dioxolanium) dications (4-6) and 2,4,6-triphenylene tris(1,3-dioxolanium) trication (7) have been prepared by the ionization of the corresponding 2-methoxyethyl benzoates in FSO(3)H or CF(3)SO(3)H at 40 and 60 degrees C, respectively. The charge delocalization in these carbocations was probed by (13)C NMR chemical shifts and substantiated by GIAO/DFT calculations. Relatively
邻,间和对亚苯基双(1,3-二氧杂鎓)双阳离子(4-6)和2,4,6-三亚苯基三(1,3-二氧杂鎓)三阳离子(7)的制备方法是分别在40和60摄氏度下在FSO(3)H或CF(3)SO(3)H中将相应的2-甲氧基乙基苯甲酸酯电离。通过(13)C NMR化学位移探测这些碳阳离子中的电荷离域,并通过GIAO / DFT计算证实。相对较少的电荷离域到碳酸盐化7的芳环中。碳酸盐4和5的C(+)-Ar键周围的旋转势垒也估计为8-10 kcal / mol。