Microwave spectrum,conformational preference,barrier to internal rotation,and centrifugal distortion of 1-amino-2-propanol

The microwave spectrum of CH₃CH(OH)CH₂NH₂ has been investigated in the 26.5–39.7 GHz region. One rotamer with an intramolecular hydrogen bond formed between hydroxyl and ammo groups was assigned. This conformation is also characterized by having the methyl group anti to the amino group. Other forms, if they exist, must be at least 1 kcal mole^?1 less stable. Four vibrationally excited states belonging to three different normal modes were assigned and the barrier to internal rotation of the methyl group was found to be 3173 ± 100 cal mole^?1.