Studies On The Oxidation Of Dihydropyrimidinones And The Nitration Of 1,3,5-trisubstituted Pyrazolines With NO~+

The thesis mainly reports studies on the oxidation of dihydropyrimidinones and the nitration of 1,3,5-trisubstituted pyrazolines with NO⁺.It is divided into three parts.The first part reviews special features of NO⁺,its history and reaction with organic molecules.The second part shows that nitrosonium tetrafluoroborate(NO⁺BF₄^-) oxidizes 3,4-dihydropyrimidin-2(1H)-ones(DHPMs) to pyrimidin-2(1H)-ones in acetonitrile at room temperature in high yields.This entry offers advantages like mild reaction conditions,simple operations and almost quantitative yields.It is found that the one half of NO⁺BF₄^- stoichiometric amount is consumed.Hence,it serves a two-electron oxidant.The reaction mechanism is discussed.The third part describes the nitration of 1,3,5-trisubstituted pyrazolines with NO⁺. The reaction uniquely occurs at the para position of N-benzene ring.This entry offered several advantages like mild reaction conditions,short reaction time and good yields of products.