Cleavage of substituted dispiro [bis(3′-aminoindene)-1′, 4;1′,5-(1,3-dithiolanes)] by means of transition metal salts

Dispiro[bis(3-aminoindene)-1,4;1,5-(1,3-dithiolanes)] react readily with Cu⁺, Ag⁺, Hg⁺, and Hg²⁺ salts to give the corresponding bis(1-imino-3-indenyls) and methanedithiol derivatives. Bis(1-oxo-3-indenyls) are formed when the reaction is carried out in the presence of water. The reactivities of the 1,3-dithiolanes were examined with allowance for electronic and steric factors, and the reactivities of the metal cations were examined from the point of view of Pearson's theory. Methods for the alternative synthesis of the compounds obtained were found, and their IR and PMR spectra are discussed.Communication 10 from the series ,-Unsaturated Thio Compounds. See [1] for communication 9.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 329–333, March, 1979.     

Protonation of some cyclic β-Aminovinylthiones and β-aminovinylketones

Conclusions The NMR method was used to study the protonation of 3-N,N-dimethylammo-5,5-dimethyl-3-cyclohexene-1-thione, 3-N,N-dimethylamino-2-phenylidene-1-thione, and their oxygen analogs. The protonation center for these compounds is different, and is, respectively, N and O, and S and 2-C.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2091–2094, September, 1976.     

Silicon-containing dimethylphosphoric acid amides

α-Silylmethylamines MeNHCH₂SiMen(OMe)_3?n (n=0, 2) were involved into Todd-Atherton reaction with (MeO)₂P(O)H giving N-methyl-N-trimethoxysilylmethyl-and N-methyl-N-dimethyl-(methoxy)silylmethylamides of dimethylphosphoric acid. A reaction of these compounds with BF₃·Et₂O led to the formation of the corresponding N-methyl-N-trifluoro-and N-methyl-N-(dimethyl)fluorosilylmethylamides of dimethylphosphoric acid. (MeO)₂P(O)N(Me)CH₂SiF₃ existed as an (O-Si)-chelate with a pentacoordinate silicon due to the occurrence of a rare and unstudied intramolecular coordinating interaction P=O → Si.     

Performance of the low pressure MWPCs for f ission fragments under a high background

Two couples of low pressure multi-wire proportional chambers (MWPC) were located in the target chamber to detect fission fragments in a hypernuclei producing experiment at Thomas Jefferson National Laboratory (Jlab). In the experiment, a continuous wave (CW) electron beam was applied to form hypernuclei by electromagnetic interaction. In the target chamber, the high energy (1.853 GeV) and high intensity (500 nA) primary electron beam caused a high particle background, which influenced the detection of the fission fragments. This report described the design of the MWPCs and studied the fission-fragment detecting performance of them under such a high background. The efficiency of the MWPCs was given with the help of a high resolution kaon spectrometer. At the same time, the background particles were discussed with a Monte Carlo code based on GEANT4.