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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.
Methanolysis of N-acetoxy-N-n-propyloxy-N’,N’-dimethylurea in different conditions
(Deuton-X Ltd., 2014) Shtamburg, V. G.; Tsygankov, A. V.; Shtamburg, V. V.; Anishchenko, A. A.; Mazepa, A. V.; Kostyanovsky, R. G.
The methanolysis of N-acetoxy-N-n-propyloxy-N’,N’-dimethylurea in the presence of strong acids at room temperatures or in the boiling methanol yields N,N-dimethoxy-N’,N’-dimethylurea as final product. Primarily the nucleophilic substitution acetoxy group at nitrogen on methoxy group arises. At second stage the transesterification of N,N-dialkoxyamino group of formed N-methoxy-N-n-propyloxy-N’,N’-dimethylurea take place.