PROTONATION AND DEPROTONATION OF HYDROXAMIC ACIDS - AN MO AB-INITIO STUDY

Ab initio molecular orbital calculations with 4-31G//4-31G, 6-31G//4- 31G and 6-31+G//4-31G basis sets have been used to examine the structu re, relative energy, protonation and deprotonation of a series of seve n hydroxamic acids in the gas phase. The results show that hydroxamic acids are predominantly in the E-TS form and that the most probable pr otonation site is the carbonyl oxygen atom, while deprotonation procee ds by loss of NH hydrogen.