New discoveries in chemical research and development in 2021, The transformation of simple hydrocarbons into more complex and valuable products via catalytic C–H bond functionalisation has revolutionised modern synthetic chemistry. 91-40-7, Name is 2-(Phenylamino)benzoic acid, SMILES is O=C(O)C1=CC=CC=C1NC2=CC=CC=C2, in an article , author is Duan, XG, once mentioned of 91-40-7, Category: isothiazole.
Activated allylic compounds react with trithiazyl trichloride, (NSCl),, to give 1,2,5-thiadiazoles 1 and isothiazoles 2. An allylic 2-substituent normally prevents formation of an aromatic 1,2,5-thiadiazole, and isothiazole formation becomes the major pathway. Simple allylic compounds are not very reactive towards (NSCl)(3) but a terminal electron withdrawing group (CO2Et) enhances the reactivity. With unsymmetrical allylic compounds, isothiazole formation is regiospecific placing the more electron withdrawing group adjacent to the ring sulfur. 1,3-Diketones give 3-acyl-1,2,5-thiadiazoles; unsymmetrical 1,3-diketones give these thiadiazoles regiospecifically, explicable by cyclisation of an intermediate onto the more reactive carbonyl group. 1,4-Diketones give 3,4-diacyl-1,2,5-thiadiazoles; thus 1,2-dibenzoyl-ethane, -ethene and -ethyne all give 3,4-dibenzoylthiadiazole (40-44%). Many of these trithiazyl trichloride reactions provide attractive one-step routes to 1,2,5-thiadiazoles and isothiazoles.
Note that a catalyst decreases the activation energy for both the forward and the reverse reactions and hence accelerates both the forward and the reverse reactions. you can also check out more blogs about 91-40-7. Category: isothiazole.
Reference:
Isothiazole – Wikipedia,
,Isothiazole – ScienceDirect.com