Creation of Thio and Selenocyanate Derivatives of 4-quinolone via Regioselective C-H Bond Functionalization Under Ambient Conditions

An operationally simple C-SCN and C-SeCN bond formation technique to generate different SCN/SeCN substituted 4-quinolone derivatives using NH4SCN/KSeCN in excellent yields was developed. The versatility of this protocol has successfully been demonstrated by extension of the suitable reaction conditions to the substrates having different substituents. This regioselective C-H bond functionalization approach provides a direct access of structurally diverse 3-thiocyanated/selenocyanated 4-quinolone derivatives. Moreover, this new method does not require any transition metal catalyst and pre-requisite -NH protection of 4-quinolone derivatives. Antimicrobial effects (Zone Inhibition test and MIC analysis) were determined with both SCN/SeCN substituted 4-quinolone derivatives