On December 20, 2001, Gross, Wibke; Hoeffkes, Horst; Martin, Hans-Dieter; Moeller, Hinrich; Oberkobusch, Doris published a patent.Quality Control of 2-(2,3-Dihydro-1H-inden-1-ylidene)malononitrile The title of the patent was Hair dyeing compositions containing quinoxaline derivatives. And the patent contained the following:
Hair dye compositions contain at least one quinoxaline derivative containing e.g., C1-4 alkenyl, hydroxyalkyl, carboxyalkyl groups, and halo groups. Thus, 1,1,3-trimethylcyclo-2-penten[1,2-b]quinozaline-2-carboxaldehyde (I) was prepared in a seies of steps and formulated into a hair dye formulation containing I 4.4, Natrosol 250HR 2.0 and water to 100.0 g. The experimental process involved the reaction of 2-(2,3-Dihydro-1H-inden-1-ylidene)malononitrile(cas: 2510-01-2).Quality Control of 2-(2,3-Dihydro-1H-inden-1-ylidene)malononitrile
The Article related to hair dye quinoxaline preparation, Essential Oils and Cosmetics: Hair Preparations and other aspects.Quality Control of 2-(2,3-Dihydro-1H-inden-1-ylidene)malononitrile
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts