title: Observation of room temperature B-Cl activation of the HCB11Cl11(-) anion and isolation of a stable anionic carboranyl phosphazide.
abstract: The perchlorinated carba-closo-dodecaborate anion is typically inert toward B-Cl functionalization. We present here the observation of two competing reactions that occur with this anion at ambient temperature. When this molecule is treated with n-BuLi and subsequently reacted with tosyl azide, a cycloaddition occurs and results in chloride substitution at a B-Cl vertex. The competing and dominant pathway is a substitution reaction to form the azide N3CB11Cl11(-). This rare anionic carboranyl azide reacts with PPh3 in FC6H5 to afford a stable anionic phosphazide. When dissolved in tetrahydrofuran, the phosphazide is in equilibrium with free PPh3 and N3CB11Cl11(-). Both the triazole and phosphazide are characterized by single-crystal X-ray diffraction, NMR and IR spectroscopy, and high-resolution mass spectrometry.
authors.affiliation: Department of Chemistry, University of California at Riverside (UCR) , Riverside, California 92521, United States.
authors.forename: Allen L
authors.initials: AL
authors.lastname: Chan
authors.forename: Javier
authors.initials: J
authors.lastname: Fajardo
authors.forename: James H
authors.initials: JH
authors.lastname: Wright
authors.forename: Matthew
authors.initials: M
authors.lastname: Asay
authors.forename: Vincent
authors.initials: V
authors.lastname: Lavallo