Microwave Spectra of 2-Methylpyridine 1-oxide and 2-Methyl-d₃-pyridine 1-oxide

Abstract

The microwave spectra of 2-methylpyridine 1-oxide and 2-methyl-d₃-pyridine 1-oxide were observed in the frequency range from 16 to 34GHz. The transitions of the ground state a-type R-branch, b-type R-branch, and b-type Q-branch were assigned and the followingrotational constants for the ground state were determined: The I_c-I_a-I_b value of the principal moments of inertia calculated from the above rotationalconstants is_-3.12uA² for the normal species, and -6.20uA² for the methyl-d₃ species. These values indicate that the molecate frame of CH:CHCH:CHC(CH)N→O is planar.