Department of Chemistry , University of California , Riverside , California 92521 , United States.
J Am Chem Soc. 2019 Jan 30;141(4):1484-1488. doi: 10.1021/jacs.8b13204. Epub 2019 Jan 16.
The reaction of (Bu)ArP (1a-h), where the para position of the Ar group contains electron-donating or electron-withdrawing groups, with sulfated zirconium oxide partially dehydroxylated at 300 °C (SZO) forms [(Bu)ArPH][SZO] (2a-h). The equilibrium binding constants of 1a-h to SZO are related to the p K of [(Bu)ArPH]; RP that form less acidic phosphoniums (high p K values) bind stronger to SZO than RP that form more acidic phosphoniums (low p K values). These studies show that Brønsted acid sites on the surface of SZO are not superacidic.
（Bu）ArP（1a-h）与在 300°C 下部分脱羟的硫酸锆反应形成[(Bu)ArPH][SZO]（2a-h），其中 Ar 基团的对位含有供电子或吸电子基团。1a-h 与 SZO 的平衡结合常数与[(Bu)ArPH]的 p K 有关；形成较弱酸性膦（高 p K 值）的 RP 比形成较强酸性膦（低 p K 值）的 RP 与 SZO 的结合更强。这些研究表明，SZO 表面的 Brønsted 酸位不是超强酸性的。
