Aqueous ethanol: a suitable medium for the diastereoselective Diels–Alder reaction mediated by chiral bases

Abstract

The effect of aqueous ethanol medium on the outcome of a DielsÁAlder (DA) reaction with regard to yields, reaction time, and the stereoselectivity observed has been studied. When the reaction between anthrone and (R)-(')-N-a-methylbenzylmaleimide was carried out in aqueous ethanol in presence of achiral base no diastereoselectivity could be obtained. Moderate diastereoselectivity could be achieved in presence of chiral bases. Use of biodegradable aqueous ethanol solvent for the reaction and stereoselective nature of the reactions studied provide a greener approach.

Hydrophilic Conjugated Polymers for Sustainable Fabrication of Deep‐Red Light‐Emitting Electrochemical Cells

“…[ 4 ] Therefore, pure ethanol, water, and a mixture of ethanol and water can be ideal solvents with an attractive combination of suppressed health hazards and low ecological footprint during both synthesis and usage. [ 4b,5 ] However, the use of water as a solvent should be exercised with caution, particularly during recycling, since it otherwise can result in contamination of critical water resources. [ 6 ]…”

Synthesis of new 1H‐spiro[acridine‐9,3′‐indoline]‐1,2′(2H,10H)‐dione derivatives using aqueous ethanol as a reaction medium

“…Aqueous ethanol possesses various attractive advantages, such as nonvolatility, recyclability, easy operation, and low cost. There are several reports about the applications of aqueous ethanol in organic reactions such as Diels-alder reaction [31], dehydrobromination-rearrangement, thermal electro-cyclizations [32], Hantzsch reaction [33], Claisen Schmidt condensation [34], N-Mannich base reaction [35], and Biginelli reaction [36]. In this present work, we have proposed a new synthetic method for the access of novel 3,3-dimethyl-3,4-dihydro-1H-spiro[acridine-9,3 0indoline]-1,2 0 (2H,10H)-diones derivatives under catalystfree conditions (Scheme 1).…”

Green Synthesis of Pyrazole and Oxazole Derivatives

“…Mirgane et al . utilized aqueous ethanol as suitable medium for diastereoslective Diels–Alder reaction of anthrone and ( R )‐(+)‐ N ‐α‐methylbenzylmaleimide using chiral bases . Bioethanol could be the green alternative for sustainable future .…”