Premium
Viability of 4,5‐Dihydro‐1,2,3,4‐oxatriazoles Reinvestigated
Author(s) -
Firdous Samia,
Banert Klaus,
Auer Alexander A.
Publication year - 2011
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201100231
Subject(s) - intramolecular force , cycloaddition , quantum chemical , endothermic process , chemistry , chemical shift , computational chemistry , nuclear magnetic resonance spectroscopy , stereochemistry , organic chemistry , molecule , adsorption , catalysis
Abstract The first procedures to prepare 4‐bromo‐4‐methylpentanal and 4‐azido‐4‐methylpentanal are reported. The latter compound and also the parent 4‐azidobutanal do not lead to 4,5‐dihydro‐1,2,3,4‐oxatriazoles by intramolecular 1,3‐dipolar cycloaddition, although it was claimed to be so in the literature. The NMR spectroscopic data of such heterocycles reported previously do not agree with those of similar substances and are incompatible with 13 C NMR spectroscopic chemical shifts calculated by quantum chemical methods in the presented work. These calculations show furthermore that the intramolecular cycloaddition of 4‐azidobutanals to give the title compounds is strongly endothermic and thus most probably not possible.