213 research outputs found
1-Alkoxyamino-4-dimethylaminopyridinium derivatives as new representatives of O–N–N⁺ geminal systems and their structure
Geminal System O-N-O: XRD Studies of Structure of Cyclic N,N-dialkoxyderivatives of Amines and Ureas
Alcoholysis of N-acetoxy-N-alkoxycarbamates. Synthesis of NH-N,N-dialkoxyamines from N,N-dialkoxycarbamates
The alcoholysis of N-acetoxy-N-alkoxycarbamates by methanol or ethanol at 20 – 40 °C yields N,N-dialkoxycarbamates and acetic acid. At the lower temperature the competitive formation of N,N’-bis(alkoxycarbonyl)-N,N’-bis(alkoxy)hydrazines can occur. The alkaline hydrolysis of N,N-dialkoxycarbamates yields NH-N,N-dialkoxyamines
N,N-Dimethoxy-N-tert-alkylamines: new synthesis methods and the crystal structure of the precursor
Under the methanolysis of N-methoxy-N-(1-pyridinium)amines salts 1a–c, nucleophilic substitution occurs at the nitrogen atom to form N,N-dimethoxyamines 2a,b; the crystal structure of precursor 1c has been studied
Methanolysis of N-acetoxy-N-n-propyloxy-N’,N’-dimethylurea in different conditions
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
N,N-Dimethoxy-N-tert-alkylamines: new synthesis methods and the crystal structure of the precursor
Under the methanolysis of N-methoxy-N-(1-pyridinium)amines salts 1a–c, nucleophilic substitution occurs at the nitrogen atom to form N,N-dimethoxyamines 2a,b; the crystal structure of precursor 1c has been studied
New approach to N,N-dialkoxy-N'-arylureas and N,N-dialkoxycarbamates
Methanolysis of N-chloro-N-alkoxy-N'-arylureas in the presence of silver trifluoroacetate gives the corresponding N,N-dialkoxy-N'‑arylureas, whereas N-chloro-N-alkoxycarbamates react with alcohols in the presence of silver trifluoroacetate to afford N,N-dialkoxycarbamates
Pyramidal amide nitrogen in N-acyloxy-N-alkoxyureas and N-acyloxy-N-alkoxycarbamates
The XRD studies of N-acyloxy-N-alkoxyamides 1, 2 have revealed a highly pyramidal configuration of amide nitrogen in the O–N–O group
N-Chloro-N-alkoxyureas: synthesis, structure and properties
The XRD studies of N-chloro-N-alkoxyureas 1, 2 have revealed the high pyramidality of the amide nitrogen in the O–N–Cl group caused by nO–s*N–Cl anomeric effect, the other sequence of this effect is anionic lability of the chlorine atom; nucleophilic substitution at the nitrogen depends on the N'-substitutent nature: chlorine atoms in ureas 1 and 5 are replaced by outer nucleophile whereas, under the same conditions, ureas 2–4 undergo cyclization into 1-alkoxybenzimidazolin-2-ones 10–12
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