Solid State and Solution Structures ofO-Alkyl- and ofO-Acyl Derivatives of 1-Hydroxypyridine-2(1H)-thione

✍ Scribed by Hartung, Jens ;Hiller, Margit ;Schwarz, Michaela ;Svoboda, Ingrid ;Fuess, Hartmut

• Book ID: 102901185
• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 745 KB
• Volume: 1996
• Category: Article
• ISSN: 0947-3440
• DOI: 10.1002/jlac.199619961222

✦ Synopsis

Abstract

Although Barton's radical precursors, the O‐acyl derivatives of 1‐hydroxypyridine‐2(1__H__)‐thione 2, have been studied in detail for more than a decade, to date nothing has been reported on the solid state or the solution geometries of these molecules or the analogous oxo derivatives, the pyridones 7, 8. In view of this, selected O‐alkyl and O‐acyl derivatives of pyridinethiones and of 2‐(1__H__)pyridones have been prepared and investigated by X‐ray diffraction and NMR (COSY, NOE) experiments. The X‐ray data indicate alternating bond lengths in the carbon framework of the heterocycles 2d, 3b, 7b, and 8 and long NO bonds [1.394(4)–1.398(2) Å]. In all the compounds studied, the O‐alkyl and the O‐acyl groups are twisted out of the plane of the heterocycles, which is in accord with the VSEPR concept. Further, the thermal stabilities of thiohydroxamic acid derivatives 2, 3 and of substituted pyridones 7, 8 were studied by differential scanning calorimetry (DSC).