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Title: C(1)‐Phenethyl Derivatives of [ closo ‐1‐CB 11 H 12 ] − and [ closo ‐1‐CB 9 H 10 ] − Anions: Difunctional Building Blocks for Molecular Materials

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.

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Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Chemistry – A European Journal
Page Range / eLocation ID:
p. 17481-17494
Medium: X
Sponsoring Org:
National Science Foundation
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