Size-Selective Phase-Transfer Catalysis with Interfacially Cross-Linked Reverse Micelles

Abstract

Cross-linking of the reverse micelles (RMs) of a triallylammonium surfactant afforded organic nanoparticles with introverted cationic groups. The cross-linked reverse micelles catalyzed size-selective biphasic reaction between sodium azide and alkyl bromides. Size selectivity of up to 9:1 was obtained for alkyl bromides with similar structures. The selectivity was influenced strongly by the size of the water pool and proposed to happen as a result of the "sieving" effect of the alkyl corona. Disciplines Chemistry CommentsReprinted (adapted) with permission from Organic Letters 14 (2012) ABSTRACT Cross-linking of the reverse micelles (RMs) of a triallylammonium surfactant afforded organic nanoparticles with introverted cationic groups. The cross-linked reverse micelles catalyzed size-selective biphasic reaction between sodium azide and alkyl bromides. Size selectivity of up to 9:1 was obtained for alkyl bromides with similar structures. The selectivity was influenced strongly by the size of the water pool and proposed to happen as a result of the "sieving" effect of the alkyl corona.

Environmental Engineering of Pd Nanoparticle Catalysts for Catalytic Hydrogenation of CO2 and Bicarbonate

“…The quaternary ammonium-based Pd@ICRM from 3 was significantly more reactive than the tertiary amine-based catalysts from 2, consistent with the ion-exchange model. 29,32,[50][51][52] Nonetheless, the catalysts at this point were still rather inefficient.…”

Palladium–gold bimetallic nanoparticle catalysts prepared by “controlled release” from metal-loaded interfacially cross-linked reverse micelles

“…8 We recently reported methods to covalently capture micelles 9 and reverse micelles 10 through polymerization. Prior to our report, RMs have only been successfully captured in the original size once by Our interfacially cross-linked RMs (ICRMs) are core-shell organic nanoparticles tunable in their hydrophilic core size, 10 alkyl density on the surface, 10,12 and internal contents. 10,13 The ICRMs also served as interesting templates for the preparation of metal particles.…”

Selective C(sp3)–H Monoarylation Catalyzed by a Covalently Cross‐Linked Reverse Micelle‐Supported Palladium Catalyst

“…The design of the catalytic micelle began with identification of key properties to tune, such as the alkyl density of surfactant tails,, size of the hydrophilic core, and ligand functionalization within that core. After exploiting the hydrophilic head group and hydrophobic alkyl tail, the resulting micelles were interfacially cross‐linked to provide thermal stability, necessary for the Pd‐catalyzed C( sp 3 )–H monoarylation shown above (Scheme ).…”

“…The initial tunable property of the micelle explored was the surfactant‐alkyl density of surfactant B . The alkyl density played a significant role in the catalytic activity of the micelle, altering the number of hydrophobic tails covalently bound to a hydrophilic head group between two and three. The second property of the micelle to be evaluated was the size of the catalytic core.…”