Anion Chelation via Double Chalcogen Bonding: The Case of a Bis-telluronium Dication and Its Application in Electrophilic Catalysis via Metal–Chloride Bond Activation
作者:Benyu Zhou、François P. Gabbaï
DOI:10.1021/jacs.1c04482
日期:2021.6.16
to engage their counteranions via secondary interactions. Yet, this property has rarely been exploited for anion binding. Motivated by such an application, we have now synthesized a bis-telluronium dication ([3]2+) that was obtained as a tetrafluoroborate salt by reaction of 2,7-di-tert-butyl-9,9-dimethylxanthene-4,5-diboronic acid with phenoxatellurine difluoride and BF3·OEt2. As confirmed by the formation
人们早就知道碲阳离子通过二次相互作用与它们的反阴离子结合。然而,这种特性很少被用于阴离子结合。受此类应用的启发,我们现在合成了一种双碲二阳离子 ([ 3 ] 2+ ),它是通过 2,7-二叔丁基-9,9-二甲基氧杂蒽-4的反应获得的四氟硼酸盐, 5-二硼酸与二氟化苯氧苯胺和BF 3 ·OEt 2。[ 3 ][BF 4 ] 2 , [ 3 ] 2+结构中Te-(μ-BF 4 )-Te桥的形成证实了这一点作为对阴离子的双齿路易斯酸。[ 3 ][BF 4 ] 2也被转换成更暴露的[ 3 ][BArF 24 ] 2 ([BArF 24 ] − = [B(3,5-(CF 3 ) 2 C 6 H 3 ) 4 ] - )。后者易于电离 Ph 3 CCl,其氯阴离子结合常数比单功能模型化合物高出近 4 个数量级。这种新的双碲二阳离子的独特性质因其激活 Ph 3 的能力而进一步突出PAuCl和顺式-(Ph 3