《Millimeter-wave spectrum of 4-cyanopyridine in its ground state and lowest-energy vibrationally excited states, ν20 and ν30》 was published in Journal of Molecular Spectroscopy in 2020. These research results belong to Dorman, P. Matisha; Esselman, Brian J.; Park, Jieun E.; Woods, R. Claude; McMahon, Robert J.. Category: pyridine-derivatives The article mentions the following:
The rotational spectrum of 4-cyanopyridine (μa = 1.96 D) was recorded from 130 to 360 GHz, and the anal. of the ground state and two lowest-energy excited vibrational states was completed. Over 3900 new rotational transitions were measured for the ground state, allowing the determination of spectroscopic constants for a partial octic, distorted-rotor Hamiltonian. Over 5600 new transitions were measured for the Coriolis-coupled dyad, ν20 and ν30. A coupled-state least-squares fit of the dyad was obtained, which resulted in the precise determination of several parameters addressing the Coriolis coupling between the two states: Ga, GJa, Fbc, and FKbc. With inclusion of these terms, numerous resonance transitions associated with selection rules ΔKa = 2 or ΔKa = 4 between vibrational states were assigned and fit to low error (σfit < 50 kHz). The precise energy difference between ν20 and ν30 was determined, ΔE = 18.806554 (11) cm-1, along with the Coriolis coupling coefficient ζa20,30 = 0.8432 (8). Determination of the spectroscopic and perturbation parameters for the vibrational states permits comparison to other arenes bearing -CN or -NC substituents and sharing a similar Coriolis-coupled dyad ∼150 cm-1 above the ground state. This new data provides the foundation for an astrochem. search for 4-cyanopyridine in the interstellar medium. After reading the article, we found that the author used 4-Cyanopyridine(cas: 100-48-1Category: pyridine-derivatives)
4-Cyanopyridine(cas: 100-48-1) belongs to pyridine. Pyridine is very deactivated towards electrophilic substitution with respect to benzene. For this reason classical formylation, using methods such as the Gattermann or Vilsmeier reactions, are not generally successful. Category: pyridine-derivatives