Department of Chemistry , University of Toronto , 80 St. George St ., Toronto , Ontario M5S 3H6 , Canada.
Org Lett. 2018 Sep 7;20(17):5375-5379. doi: 10.1021/acs.orglett.8b02295. Epub 2018 Aug 27.
Diarylborinic acids (ArBOH) catalyze the C3-selective ring opening of 3,4-epoxy alcohols with aniline, dialkylamine and arenethiol nucleophiles. The regiochemical outcome is consistent with a catalytic tethering mechanism in which the borinic acid interacts with both the electrophile and the nucleophile. The rate acceleration resulting from this induced intramolecularity effect is sufficient to overcome steric biases that would otherwise favor C4-selective opening of the substituted epoxy alcohols.
二芳基硼酸（ArBOH）能够催化 3,4-环氧醇与苯胺、二烷基胺和芳硫醇亲核试剂的 C3 选择性开环反应。区域化学结果与催化键合机制一致，其中硼酸与亲电试剂和亲核试剂都相互作用。这种诱导的分子内作用产生的速率加速足以克服空间位阻偏差，否则会有利于取代的环氧醇的 C4 选择性开环。
