Question

Which of the following conjugate acids corresponds to the most basic pyridine derivative? H H H H H No OCH Coche CH(CHAR CH3 CN OCH3 11 COCH3 III CH(CH3)2 IV V

Answer 1

H conjugate acids CH3 OCH3 11 CH3 H3C CH3 CN V - IV | basic pyridine CH3 OCHZ CN CH3 H3C CH3 Iva la lla Illa Va Funda: more electron donating groups increases the eectron density in the pyridine ring. Thus, increases the basic nature. Thus, Illa and Va is the least basic CH3 OCH3 H3C CH3 Iva la lla Among -CH3, -OCH3 and -CHIPrą the electron donation order is: -OCH3 >-CHiPrz>-CH3 This means -OCH3 has the higest donating ability Thus Ila has the most electron density Thus, it has the most electron density over N-atom Thus, it is most basic Answer: lla