Geminal systems

We have determined the molecular structure of tetramethoxyhydrazine in the crystal by x-ray diffraction analysis. The molecule is centrosymmetric with trans orientation of the unshared electron pairs of the N atoms and close to cis-cis conformations of the CONOC fragments.For previous communication, see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1825–1828, August, 1989.     

Geminal systems. 15. Chemical properties of N-chloro-N-alkoxy-N-tert-alkylamines

Conclusions N-chloro-N-alkoxy-N-tert-alkylamines react exclusively with CN^– and SCN^– and partially with Et^– and AcO^– to give nucleophilic substitution products at the nitrogen atom. These compounds react with AcO^– and water to give nitroso compounds, with EtS^– and Ph₃ P to give azoxy compounds, and with AgF and AgNO₃ to give products of more complex transformations.For communication 14, see ref. [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2320–2326, October, 1981.     

Geminal systems. 16. Reactions of N-chloro-N-alkoxy-N-alkylamines with amines

Conclusions The reactions of N-chloro-N-alkoxy-N-tert-alkylamines with amines are characterized by nucleophilic substitution at the nitrogen atom with formation of the corresponding N-alkoxyhydrazines which are stable in the case of ethyleneimine and pyridine; give diazenes as in the case of MeNH₂, EtNH₂, and Me₂ or yield products of further transformations as in the case of NH₃, Me₂NH, and MeO(Me)NH. Nucleophilic substitution is repressed in the reaction with Et₂NH and Et₃ N by one-electron reduction with the formation of azoxy compounds.For Communication 15, see previous article [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2327–2334, October, 1981.     

Geminal conjugation in disulfides

Some aspects of the spatial and electronic structure of disulfides XSSX (X = H, Alk, Ph, Hal) are considered. It is shown that the growth of the geminal n_s-σ_SX* conjugation efficiency leads to a shortening of the SS bond that is more than three times as large as the simultaneous SX bond lengthening. The positive effective charge on the sulfur atom also increases as a result of this conjugation. These effects increase with the growth of - I and + M abilities of the substituents X. The SK_a line shifts and the HOMO bonding degree (Delta;n_S) have been measured by the X-ray fluorescence spectroscopy method for dialkyl disulfides (Alk = Me, Et, Pr, i-Pr, Bu, i-Bu, t-Bu, C₅H₁₁, C₈H₁₇, H₂NCH₂CH₂, CH₂CH  CH₂, CH₂Ph) and S₈. With the help of Δn_S values that are proportional to the n_S–σ_SC* conjugation efficiency, the sequence of the enhancement of the geminal conjugation efficiency has been established for the disulfides investigated. In the framework of the n_S–σ_SS* geminal conjugations, the shortening of the SS bonds in S₈ is explained. © John Wiley & Sons, Inc.     

Radical Functionalization of Geminal Difluoroalkenes

Russian Journal of Organic Chemistry - Geminal difluoroalkenes are readily available building blocks for the synthesis of a broad spectrum of organofluorine compounds. The review summarizes...     

Nature of Noninductive Geminal Interaction

In X-Y-Z atomic groups of organic and organometallic molecules, the effect of a Z atom on an X atom usually does not correspond to the electronegativity and inductive effect of the Z atom (or atomic groups in substituent Z). The possible causes of this phenomenon and the nature of the effect are discussed.     

Geminal systems. Communication 29. Reactions of N-chloro-N-methoxy-N′,N′-dimethylurea with N-nucleophiles

Conclusions In the reaction of N-chloro-N-methoxy-N,N-dimethylurea with amines, a nucleophilic substitution of the chlorine atom at the N atom takes place to form N-alkoxyhydrazines, which are stable in the reaction with Me₃N, pyridine, toluenesulfonamides, and give products of further transformations with Me₂NH and MeONHMe.For Communication 28 see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 606–610, March, 1986.     

Synthesis of Acyclic Geminal Bis-peroxides

Russian Journal of Organic Chemistry - The review covers the state of the art in methods of synthesis of acyclic geminal bis-peroxides, including bis-hydroperoxides, bis(1-hydroperoxyalkyl)...