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Документ Geminal systems 64.*N-Alkoxy-N-chloroureas and N,N-dialkoxyureas(Springer and Business Media, Inc., 2015) Shtamburg, V. G.; Kostyanovsky, R. G.; Tsygankov, A. V.; Shtamburg, V. V.; Shishkin, O. V.; Zubatyuk, R. I.; Mazepa, A. V.; Kravchenko, S. V.Molecular and crystal structures of N-alkoxy-N-chloroureas and N,N-dialkoxyureas were studied together with those of N-alkoxyureas as reference compounds. N-Alkoxy-N-chloroureas were found to have an elongated N—Cl bond and a shortened N—O(Alk) bond due to the nO(Alk)*N—Cl anomeric effect. Alcoholysis of N-alkoxy-N-chloro derivatives of urea, N´-arylureas, and carbamates in the presence of silver trifluoroacetate leads to sterically hindered N,N-dialkoxyureas, N,N-dialkoxy-N´-arylureas, and N,N-dialkoxycarbamates, respectively.Документ Synthesis and structure of new N-alkoxy-N-(1-pyridinium)urea chlorides(Deuton-X Ltd., 2016) Shtamburg, V. G.; Shtamburg, V. V.; Tsygankov, A. V.; Anishchenko, A. A.; Zubatyuk, R. I.; Shishkina, S. V.; Mazepa, A. V.; Klots, E. A.New N-[1-(4-amino)pyridinium]-N-methoxyurea chloride, N-[1-(2-amino)pyridinium]-N-methoxyurea chloride and their analogs were synthesized by N-alkoxy-N-chloroureas reaction with the proper pyridines in acetonitrile or ether solution by improved procedure. XRD study of N-[1-(4-amino)pyridinium]-N-methoxyurea and N-[1-(2 amino)pyridinium]-N-methoxyurea revealed the elongation of N-N+ bonds and some shortening of MeO-N bonds, qunonoid deformation of pyridine rings compare to it unsubstituted analog. The substantial pyramidality of central nitrogen atom in O-N-N+ moiety and N-C carbamoyl bonds difference were established too. The structure summary of N-alkoxy-N-(1-pyridinium)ureas salts and other derivatives of 1-(N-alkoxyamino)pyridinium salts has been done.