Synthesis and characterization of napthoquinone derivatives with some studies on formation of pyridinium salt / Nurul Atikah Mohd Mokhtar

The pyridinium salt 29 was prepared from 1-bromopinacolone refluxed with pyridine and tetrahydrofuran as solvent. The rate of formation of pyridinium salt according to different refluxing time was studied. r - ^ ~N 28 ^ O x ICTHzB r THF reflux R -C(CH3)3 27 29 Different refluxing time give effects on percent yield of pyrididnium salt. Increase in refluxing time give an increase in percent yield. The rate is exponential proportional to the refluxing time. There was possibility of optimum refluxing time in this reaction, but this possibility cannot be further study due to time limitation and limited starting material. The stirring with heating gave higher percent yield compared to stirring without heating. The pyridinium salt was obtained in the form of white crystal about 6.4744g. The percent yiled of this salt is 96.67%. The FTIR and NMR analysis was carried out and confirmed the structure of salt. The pyridinium salt obtained was stirred with 2-methyl-1,4 naphthoquinone and acetonitrile as solvent. The reaction between 2-methyl-l,4 naphthoquinone (naphthoquinone derivatives) with pyridinium salt was studied. The product was obtained in the form of fine red needles in 0.3268 g (26%)