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Title: Tunable Aminooxy‐Functionalized Monolayer‐Protected Gold Clusters for Nonpolar and Aqueous Oximation Reactions
Abstract

Aminooxy (–ONH2) groups are well known for their chemoselective reactions with carbonyl compounds, specifically aldehydes and ketones. The versatility of aminooxy chemistry has proven to be an attractive feature that continues to stimulate new applications. This work describes application of aminooxy click chemistry on the surface of gold nanoparticles. A trifunctional amine‐containing aminooxy alkane thiol ligand for use in the functionalization of gold monolayer‐protected clusters (Au MPCs) is presented. Diethanolamine is readily transformed into an organic‐soluble aminooxy thiol (AOT) ligand using a short synthetic path. The synthesizedAOTligand is coated on ≤2‐nm‐diameter hexanethiolate‐(C6S)‐capped Au MPCs using a ligand‐exchange protocol to afford organic‐solubleAOT/C6S (1:1 ratio) Au mixed monolayer‐protected clusters (MMPCs). The synthesis of these Au(C6S)(AOT) MMPCs and representative oximation reactions with various types of aldehyde‐containing molecules is described, highlighting the ease and versatility of the chemistry and how amine protonation can be used to switch solubility characteristics.

 
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NSF-PAR ID:
10460445
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Particle & Particle Systems Characterization
Volume:
36
Issue:
7
ISSN:
0934-0866
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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