Murphy Brendan L, Gabbaï François P
Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, United States.
J Am Chem Soc. 2024 Mar 20;146(11):7146-7151. doi: 10.1021/jacs.4c00202. Epub 2024 Mar 11.
Our growing interest in the design of pnictogen-based strategies for anion transport has prompted an investigation into the properties of three simple triarylcatecholatostiboranes (-) of the general formula (-CClO)SbAr with Ar = Ph (), -tolyl (), and -xylyl () for the complexation and transport of hydroxide across phospholipid bilayers. A modified hydroxypyrene-1,3,6-trisulfonic acid (HPTS) assay carried out in artificial liposomes shows that and are potent hydroxide transporters while is inactive. These results indicate that the steric hindrance imposed by the three -xylyl groups prevents access by the hydroxide anion to the antimony center. Supporting this interpretation, and quickly react with TBAOH·30 HO ([TBA] = [BuN]) to form the corresponding hydroxoantimonate salts [BuN][-OH] and [BuN][-OH], whereas resists hydroxide coordination and remains unperturbed. Moreover, the hydroxide transport activities of and are correlated to the +V oxidation state of the antimony atom as the parent trivalent stibines show no hydroxide transport activity.
我们对基于氮族元素的阴离子传输策略设计的兴趣与日俱增，这促使我们对三种通式为(-CClO)SbAr（其中Ar = Ph ()、对甲苯基 () 和二甲苯基 ()）的简单三芳基儿茶酚锑酸盐（-）在跨磷脂双层膜络合和传输氢氧根方面的性质展开研究。在人工脂质体中进行的改良羟基芘 - 1,3,6 - 三磺酸（HPTS）测定表明， 和 是有效的氢氧根传输体，而 无活性。这些结果表明，三个二甲苯基基团造成的空间位阻阻碍了氢氧根阴离子接近锑中心。支持这一解释的是， 和 能迅速与TBAOH·30 HO（[TBA] = [BuN]）反应形成相应的羟基锑酸盐[BuN][-OH]和[BuN][-OH]，而 则抗拒氢氧根配位且保持不变。此外， 和 的氢氧根传输活性与锑原子的 +V 氧化态相关，因为母体三价锑化合物没有氢氧根传输活性。
