Biorenewable solvent

Deep eutectic solvents have been extensively used as an alternative green and biorenewable solvents to traditional VOCs in organic synthesis. Moreover, the addition of water to the reaction crade allows the easy separation (layer separation or precipitation) of the desired organic product. In most of these reactions, DESs were not only solvents for reactants, but also catalysts. In this sense, Shankarling and co-workers reported the reaction rate improvement of the electrophilic substitution of l-aminoanthra-9,10-quinone derivatives in the eutectic mixture lChCl/2Urea as compared wifli conventional VOCs solvents such as methanol or chloroform (see reaction (a) in Scheme 20.3.1). This rate enhancement could be related to the aforementioned basic nature of this eutectic mixture (Hammet function (H ) value 10.86). At the end of the reaction, die addition of water precipitates the dibrominated product (84-95% yield). The system was easily recycled (up to five consecutive times) by evaporation of water without appreciable lost in activity. 

Other eutectic mixtures apart from ChCl-based DESs have been used as reaction media in organic synthesis. In this sense, sweet deep eutectic solvents (also ealled low melting mixtures) based on carbohydrates (i.e., maltose) have been applied as green and biorenewable solvent in the high-yield synthesis of quinazoline derivatives via one-pot three-component coupling of 2-aminoaryl ketones, aldehydes and ammonium aeetate (see Scheme 20.3.3). However, the use of these carbohydrate-based DESs is limited because i) they present relatively high melting points, and ii) their components are rather reactive. 

ChClAJrea eutectic mixtures have been applied as green and biorenewable solvent in the electrodeposition of ... 

CONCLUSIONS AND FUTURE PERSPECTIVES OF DES AS NEW GREEN AND BIORENEWABLE SOLVENT... 

This chapter clearly exemplifies the maturity gained by Deep Eutectic Solvents as new green and biorenewable solvents in different applications of modem synthesis. As the reader have noticed, a huge number of synthetic reactions and chemical processes can be presently performed in eutectic mixtures as effectively as in classical organic media. More importantly, enhanced or completely new reactivities have been in some cases observed using DESs as a solvent. Despite all these promising applications, much effort is still needed in order to widen the utilization of DESs as green, low toxic and biocompatible reaction medium. 

Handy, S.T., Okello, M. and Dickenson, G. (2003) Solvents from biorenewable sources ionic liquids based on fructose. Org. Lett., 5, 2513. 

Green and Biorenewable Reaction Media, In G. Wypych, editor Handbook of Solvents, 2nd ednUse, Health, and Environment. 2nd edn, Vol. 2, ChemTec Publishing Toronto (2014). 

Professor Rogers s technology combines two major principles of green chemistry developing environmentally preferable solvents, and using biorenewable feedstocks to form advanced materials. Professor Rogers has found that cellulose from virtually any source (fibrous. 

ETHYL LACTATE A BIORENEWABLE AGROCHEMICAL SOLVENT FOR FOOD TECHNOLOGY... 

Ethyl lactate a biorenewable agrochemical solvent for food technology... 

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