ChCl:Urea deep eutectic solvent as a green media for one-pot, three-component catalyst-free synthesis of spiro-benzoxazole derivatives

•Synthesis of seventeen new derivatives of spiro-benzoxazoles with potential biological activity.•Using eutectic mixture of ChCl:Urea as a green reaction media.•Development a new synthetic method in the absence of any base and catalyst.•Taking advantage of multicomponent reactions for the synthesis of new compounds.•Operational simplicity with no column chromatography to purify products. An efficient catalyst-free procedure is reported for the one-pot three-component synthesis of novel spiro-benzoxazole derivatives via the condensation reaction of isatins, dihydrobenzoxazole compounds, and malono derivatives in ChCl:Urea deep eutectic solvent, as a green reaction medium. Spiro-benzoxazoles were easily extracted from the reaction mixture, by adding water, and isolated in good to excellent yields.