Well, Green chemistry has principles which have been relatively achieved as the researcher has indicated in the paper. i.e by using non toxic base (NaOH) and a green technology (microwave) in the syntheses. But, the use of ethanol as a solvent in my opinion is not completely green idea. But over all green as explained above.

Do feel free to comment if any. Thanks.

Ethanol is green solvent,, because you produce ethanol from the green plants like Brazil used ethanol as a fuel, so it can be a green solvent, and microwave technique used for the synthesis purpose due to shorter reaction time and better quality product, like in biodiesel production.

NaOH in ethanol is not a green reagent for synthesis as NaOH is hazardous to the environment.