The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Synthesis of new derivatives of 1,2,5-triazepino[1,2-a]cinnoline. II. Synthesis of haloacyl derivatives of 4-oxo-1,2,3,4-tetrahydrocinnoline》. Authors are Kwapiszewski, Wincenty; Stanczak, Andrezej; Groszkowski, Stefan.The article about the compound:2,3-Dihydrocinnolin-4(1H)-one hydrochloridecas:137195-33-6,SMILESS:O=C1CNNC2=C1C=CC=C2.[H]Cl).Category: cinnoline. Through the article, more information about this compound (cas:137195-33-6) is conveyed.
Stirring 1,2,3,4-tetrahydrocinnolin-4-one (I) with BrCH2COCl (II) in H2O at 0° gave 76% III (X = Br, R = R1 = R2 = H). III (X = Cl, R1 = R2 = H; R = Cl, Me, MeO; R = R1 = H, R2 = Cl, Me; R = H, R1 = R2 = MeO) were prepared analogously in 49-74% yields from the appropriately substituted I and ClCH2COCl (IV). When I and II were refluxed 10 h in C6H6, diacetylation occurred to give 67% V (X = Br, R1 = R2 = H). V (X = Cl, R1 = R2 = MeO; R1 = H, R2 = Cl, Me) were prepared analogously. V (X = Cl, R1 = R2 = H) was obtained from the corresponding III and IV in the presence of Et3N. Refluxing I 10 h with ClCH2CH2COCl in C6H6 gave 54% VI, which was also obtained as a byproduct when a similar reaction was carried out at 0° in CHCl3; the main product (60% yield) was 2-(3-chloropropionyl)-1,2,3,4-tetrahydrocinnolin-4-one.
In some applications, this compound(137195-33-6)Category: cinnoline is unique.If you want to know more details about this compound, you can contact with the author or consult more relevant literature.
Reference:
Cinnoline – Wikipedia,
Cinnoline – an overview | ScienceDirect Topics