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08:12
Surface Functionalization of Metal-Organic Frameworks for Improved Moisture Resistance
Published on: September 5, 2018
Organic syntheses on an icosahedral borane surface: closomer structures with twelvefold functionality.
Tiejun Li1, Satish S Jalisatgi, Michael J Bayer
1Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California 90095, USA.
Journal of the American Chemical Society
|December 15, 2005
Summary
Novel ester-linked boron clusters, known as closomer esters, were synthesized using various methods. A general strategy using 1,1'-carbonyldiimidazole-activated carboxylic acids proved effective for creating these versatile boron cluster derivatives.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Boron Cluster Chemistry
Background:
- The [closo-B12(OH)12]2- boron cluster is a unique icosahedral structure with potential applications.
- Functionalization of boron clusters is crucial for tailoring their properties.
- Ester linkages offer a versatile route for modifying boron cluster surfaces.
Purpose of the Study:
- To develop and describe synthetic methods for novel ester-linked derivatives of the [closo-B12(OH)12]2- boron cluster (closomer esters).
- To establish a general and efficient synthetic strategy for creating these closomer esters.
- To demonstrate the compatibility of the developed methods with diverse peripheral functional groups.
Main Methods:
- Reaction of bis(tetrabutylammonium)-closo-dodecahydroxy-dodecaborate with activated carboxylic acids, acid chlorides, anhydrides, and vinyl esters.
- Utilizing 1,1'-carbonyldiimidazole (CDI) for carboxylic acid activation as a general strategy.
- Employing elevated temperatures and pressures to accelerate synthesis.
- Using immobilized scavenger reagents for efficient purification of closomer esters.
Main Results:
- Successful synthesis of dianionic dodeca-ester closomers using multiple synthetic routes.
- Identification of the 1,1'-carbonyldiimidazole method as a general and reliable synthetic strategy.
- Demonstration of compatibility with various peripheral functional groups, including terminal amino groups.
- Preparation and subsequent acetylation of a closomer ester with twelve terminal amino groups.
Conclusions:
- Developed versatile synthetic methodologies for novel ester-linked boron cluster derivatives (closomer esters).
- The 1,1'-carbonyldiimidazole activation method is a robust and generalizable approach for closomer ester synthesis.
- The methodology allows for the incorporation of diverse functional groups, expanding the potential applications of boron clusters.
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