Can I read The Conformation of Substituted Hydroxyureas and Hydroxythioureas in Solution on EtoBox?

The Conformation of Substituted Hydroxyureas and Hydroxythioureas in Solution by Jiří Mollina, Pavel Fiedlerb, Václav Jehličkac and Otto Exnerb is a scholarly article available to read on EtoBox.

What is The Conformation of Substituted Hydroxyureas and Hydroxythioureas in Solution about?

The conformation of 1,3-disubstituted 1-hydroxyureas Ia-d and 1-hydroxythioureas IIa-d, mostly with aromatic substituents, was investigated by means of dipole moments in dioxan solution and by infrared spectroscopy. The results are concordant for the two classes of compounds. The most populated conformation is near to the planar Z, E, ap form (A), or possibly with the hydroxyl hydrogen out of the N-C-N-O plane (between A and B). This finding from the analysis of dipole moments is corroborated by the presence of the amide-II band and absence of intramolecular hydrogen bonds. While the conformation of hydroxyureas seems to be virtually uniform, in the case of hydroxythioureas a less abundant rotamer may be present in nonpolar solvents, possibly the E, E, sp (G) or E, E, ap (F) form. The conformation found (A) is not explicable in terms of hydrogen bonds and/or steric factors when compared to symmetrically substituted ureas (thioureas) and to N-alkylhydroxamic acids.

Author

Jiří Mollina, Pavel Fiedlerb, Václav Jehličkac and Otto Exnerb

Published

1979

Language

EN