Thermoregulated Microemulsions by Cyclodextrin Sequestration: A New Approach to Efficient Catalyst Recovery

Abstract

The combination of imidazolium surfactants with alpha-cyclodextrins (CDs, in green) was used as a control element in the thermoregulated aqueous olefin hydroformylation. The self-assembly of the imidazolium surfactants (red) favors the micellization process at high temperatures, whereas at lower temperatures the complexation of the surfactant monomers into the alpha-CDs is favored.

Interactions between cyclodextrins and cellular components: Towards greener medical applications?

“…As their water solubility differs significantly, a great variety of modified CDs has been developed to improve the stability and the solubility of inclusion complexes [8][9][10]. Nowadays, CDs are widely applied in many fields [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] due to their host-guest properties, their origins (produced from starch by enzymatic conversion), their relatively low prices, their easy modifications, their biodegradability and their low toxicity. Moreover, CDs are able to interact with a wide range of biomol- ecules opening the way for many biological applications.…”

Unconventional Approaches Involving Cyclodextrin-Based, Self-Assembly-Driven Processes for the Conversion of Organic Substrates in Aqueous Biphasic Catalysis

“…The catalytic performance was significantly improved as the local concentrations in catalyst and substrates were significantly increased at the micelle interface. For example, CDs and imidazolium surfactants were combined to promote the formation of micelles in thermoregulated Rh-catalyzed HF of alkenes [26]. More precisely, the alkyl chain of surfactants such as [C 12 MIM][X] and [C 16 MIM][X] (X = Br or TfO) included into the α-CD's cavity at room temperature while both components dissociated at 80 • C to trigger self-aggregation of imidazolium salts into micelles.…”

N,N′‐Methylenediimidazolium Salts: From Self‐Assembly to an Efficient DNAse Protection System

“…[5] On the other hand, among reported applications of imidazolium salts, [6] we demonstrated previously that N-alkyl-N-methylimidazolium can be very useful in micellar catalysis. [7] The methylene diimidazolium cation is useful in orienting the lateral alkyl chains. In analogy with the conventional double-tailed surfactants, N,N'-dialkylmethylenediimidazolium dication salts ([C n C n DIM][X] 2 ) can be versatile building blocks to obtain stable vesicles.…”