33243-89-9Relevant academic research and scientific papers
1,3-Oxazines and Related Compounds. XII. Facile Synthesis of 2,4-Disubstituted 6H-1,3-Oxazin-6-ones
Yamamoto, Yutaka,Morita, Yasuo,Minami, Keiko
, p. 1980 - 1986 (2007/10/02)
A convenient method for synthesis of 2,4-disubstituted 6H-1,3-oxazin-6-ones (8) was developed.Acylaminoalkylidene-1,3-dioxane-4,6-diones (5a-l), which were prepared from N-acylimidates (3a-l) and Meldrum's acid (4), readily underwent thermolysis upon heating, leading to a variety of 2,4-disubstituted 6H-1,3-oxazin-6-ones (8a-l).Keywords - 6H-1,3-oxazin-6-one; Meldrum's acid; acylaminoalkylidene-1,3-dioxane-4,6-dione; N-acylimidate; thermolysis
Synthesis and Structure of Alkyl N-Acylimidates
Kupfer, Rainer,Nagel, Michael,Wuerthwein, Ernst-Ulrich,Allmann, Rudolf
, p. 3089 - 3104 (2007/10/02)
Alkyl N-acylimidates 1 are prepared more easily and in higher yields than before by reaction of alkyl imidate hydrochlorides 5 with acyl halides 7 in the presence of 2.2 mol of base (14 examples).The X-ray analysis of a crystalline derivative (1dbd) shows, that the C=N- and C=O parts are twisted significantly (torsional angle 77.6 deg).The stereochemical, dynamic and electronic properties of the compounds 1 are interpreted by means of ab initio 3-21 G calculations on conformers of the parent system HO-CH=N-CH=O (8).Low rotational (ca. 6 kcal/mol) and inversional (max. 8 kcal/mol) barriers indicate the many favourable electronic interactions between the C=N- and the C=O groups in such N-functionalised imine derivatives.The compound 1 are significantly higher in energy than bisacylamines and are therefore suggested to be superior, more reactive synthetic C-N-C building blocks.The spectroscopic properties (IR, 13C- and 1H NMR, MS) are given and discussed.
