skip to main content

Title: Quantitative Assessment of B−B−B, B−H b −B, and B−H t Bonds: From BH 3 to B 12 H 12 2−
 ;  ;  ;  
Publication Date:
Journal Name:
Page Range or eLocation-ID:
p. 1967-1977
Wiley Blackwell (John Wiley & Sons)
Sponsoring Org:
National Science Foundation
More Like this
  1. Abstract

    C(1)‐vinylation of [closo‐1‐CB9H10](A) and [closo‐1‐CB11H12](B) with 4‐benzyloxystyryl iodide followed by hydrogenation of the double bond and reductive deprotection of the phenol functionality led to C(1)‐(4‐hydroxyphenethyl) derivatives. The phenol functionality was protected as the acetate. The esters were then treated with PhI(OAc)2and the resulting isomers were separated kinetically (for derivatives of anionA) or by chromatography (for derivatives of anionB) giving the difunctionalized building blocks in overall yields of 9 % and 50 %, respectively. A similar series of reactions was performed starting with anionsAandBand 4‐methoxystyryl bromide and iodide. Significant differences in the reactivity of derivatives of the two carborane anions were rationalized with DFT computational results. Application of the difunctionalized carboranes as building blocks was demonstrated through preparation of two ionic liquid crystals. The extensive synthetic work is accompanied by single crystal XRD analysis of six derivatives.

  2. Abstract

    Keggin‐type polyaluminum cations belong to a unique class of compounds with their large positive charge, hydroxo bridges, and divergent isomerization/oligomerization. Previous reports indicated that oligomerization of this species can only occur through one isomer (δ), but herein we report the isolation of largest Keggin‐type cluster that occurs through self‐condensation of four ϵ‐isomers ϵ‐GeAl128+to form [Ge4O16Al48(OH)108(H2O)24]20+cluster (Ge4Al48). The cluster was crystallized and structurally characterized by single‐crystal X‐ray diffraction (SCXRD) and the elemental composition was confirmed by ICP‐MS and SEM‐EDS. Additional dynamic light scattering experiments confirms the presence of theGe4Al48in thermally aged solutions. DFT calculations reveal that a single atom Ge substitution in tetrahedral site of ϵ‐isomer is the key for the formation ofGe4Al48because it activates deprotonation at key surface sites that control the self‐condensation process.