AB INITIO STUDIES OF HINDERED ARYL ROTATIONS OF METHAQUALONE, MECLOQUA LONE, AND 3-(2,6-DIFLUOROPHENYL)-2-METHYL-4(3H)-QUINAZOLINONE

ABSTRACT

Rotational barriers for the rotation of an N-aryl group were investigated via ab initio (Hartree-Fock) calculations in methaqualone, mecloqualone and 3-(2,6-difluorophenyl)-2-methyl-4(3H)-quinazolinone. It was found that the N1 atom acquires an sp³ character in conformations with high steric hindrance. The geometrical parameters of the molecules undergo small changes intended to alleviate the steric hindrance.

Keywords:

• Hindered rotation
• 3-Aryl-2-methyl-4(3H)-quinazolinones
• Methaqualone
• Mecloqualone
• Hartree-Fock 6-31G*
• Axial chirality

ACKNOWLEDGMENTS

This work has been supported, in part, by the Professional Staff Congress – City University of New York (PSC-CUNY) Research Award Program and the U.S. Education Department Minority Science and Engineering Improvement Program.