Lega, D. A.; Chernykh, V. P.; Shemchuk, L. A. published an article in 2016, the title of the article was The study of the three-component interaction between 1-ethyl-1H-2,1-benzothiazin-4(3H)-one 2,2 dioxide, hetarylcarbaldehydes and active methylene nitriles.HPLC of Formula: 75629-62-8 And the article contains the following content:
Some peculiarities of the three-component reaction of 1-ethyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide with active methylene nitriles and hetarylcarbaldehydes have been described in this article. It has been found that if malononitrile is used, the products of the three-component reaction are 2-amino-4-hetaryl-3-cyano-6-ethyl-4,6- dihydropyrano[3,2-c][2,1]benzothiazine 5,5-dioxides irresp. of the hetaryl fragment nature in the initial aldehyde. When using Et cyanoacetate as an active methylene nitrile instead of malononitrile the reaction lost its selectivity. In this case, depending on the hetarylcabaldehyde, three different types of products were obtained, namely, 2-amino-3-alkoxycarbonyl-4-hetaryl-4H-pyrans (for pyridine-3-, pyridine-4-carbaldehydes, and furan-2-carbaldehyde), triethylammonium salt of bis(1-ethyl-1H-2,1-benzothiazin-2,2- dioxo-4-ol-3-yl)(2-thienyl)methane (for thiophen-2-carbaldehyde) or Et 2-cyano-3-(1H-indol-3-yl)acrylate (for indole-3-carbaldehyde). Formation of a stable triethylammonium salts was considered as the process competitive with formation of 2-amino-4H-pyrans. This has allowed us to propose the modified mechanism of 2-amino-4H-pyran formation. This mechanism includes formation of triethylammonium salts of bis-adducts. According to this mechanism 2-amino-3-ethoxycarbonyl-4-(2-thienyl)-4H-pyran without any impurity of bis-adduct could be selectively obtained using the three-component reaction. Triethylammonium salts of bis-adducts were obtained by direct reaction of 1-ethyl-1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide with hetarylcarbaldehydes in the presence of equimolar amounts of triethylamine. It has been shown that the three-component reaction of 1-ethyl-1H-2,1-benzothiazM(3H)-one 2,2-dioxide with active methylene nitriles and hetarylcarbaldehydes is a more effective tool for obtaining fused 2-amino-4-hetaryl-4H-pyrans compared to the stepwise approach. The experimental process involved the reaction of 2-((1H-Indol-3-yl)methylene)malononitrile(cas: 75629-62-8).HPLC of Formula: 75629-62-8
The Article related to three component reaction ethylbenzothiazinone dioxide hetarylcarbaldehyde nitrile, Physical Organic Chemistry: Ring Formation, Cleavage, Enlargement, and Contraction and other aspects.HPLC of Formula: 75629-62-8
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts