77205-52-8Relevant academic research and scientific papers
Synthesis, structure, and chemistry of new, mixed group 14 and 16 heterocycles: Nucleophile-induced ring contraction of mesocyclic dications
Block, Eric,Dikarev, Evgeny V.,Glass, Richard S.,Jin, Jin,Li, Bo,Li, Xiaojie,Zhang, Shao-Zhong
, p. 14949 - 14961 (2008/02/04)
More than 40 new 4- to 12-membered ring heterocycles containing various combinations of Group 14 and 16 elements Si, Sn, S, Se, and Te have been synthesized and fully characterized. Synthesis of these small-ring as well as medium-ring (mesocyclic) heterocycles from α,ω-dihalides is facilitated by the presence of gem-dialkylsilyl and gem-dialkylstannyl groups in the precursors. Conformations of several of the new ring systems in the solid state have been determined by X-ray crystal structure analysis. Oxidation of mixed S(Se, Te)/Si eight-membered ring mesocycles with NOPF6 or Br2 gives dications or a bicyclic dibromide, respectively, which can be characterized by NMR methods. On treatment with nucleophiles, mesocyclic dications, or the corresponding radical cations undergo ring contraction, giving five- or six-membered ring heterocycles. Photolysis of a S/Se four-membered ring heterocycle gives selenoformaldehyde, trapped in 80% yield with 2,3-dimethyl-1,3-butadiene.
INFRARED SPECTROSCOPIC STUDY OF VERY LOW PRESSURE PYROLYSIS PRODUCTS OF CYCLOSILTHIANES AND 3,3-DIMETHYL-3-SILATHIETANE ISOLATED IN ARGON MATRICES. A NEW SOURCE OF 1,1-DIMETHYL-1-SILAETHYLENE (Me2Si=CH2), THIOFORMALDEHYDE (H2C=S) AND DIMETHYLSILANTHIONE (Me2Si=S)
Gusel'Nikov, L.E.,Volkova, V.V.,Avakyan, V.G.,Nametkin, N.S.,Voronkov, M.G.,et. al.
, p. 173 - 188 (2007/10/02)
The products of very low pressure pyrolysis (VLPP) of hexamethylcyclotrisilthiane (I), tetramethylcyclodisilthiane (II) and 3,3-dimethyl-3-silathietane (III) were isolated in Ar matrices and were studied by IR spectroscopy.The only pyrolysis product of I was cyclosilthiane II, a dimer of transient dimethylsilanthione (Me2Si=S) (IV).The starting material was recovered on pyrolysis of II.Thermal decomposition of III involves three intermediate unsaturated compounds: dimethylsilaethylene (Me2Si=CH2) (V) and thioformaldehyde (H2C=S) (VI), both isolated in Ar matrix at 10 K, as well as silanthione IV fixed in the matrix in a form of the cyclic diemr II.The latter was also observed in the study of copyrolysis of 1,1-dimethyl-1-silacyclobutane and thietane, being authentic sources of intermediates V and VI.IR spectra of starting compounds I, II and III isolated in Ar matrices were obtained.The theoretical structure of IV and force constant F(Si=S) were determined by the CNDO/2 method.With regard to CNDO/2 errors, Si=S bond distance and F(Si=S) are equal to 1.993 Angstroem and 4.72 mdyn/Angstroem, respectively.Calculation of normal vibrations resulted in the following values of vibrational frequencies of dimethylsilanthione (cm-1): 884 νs(SiC2) (A1), 735 νas(SiC2) (B2), 626 νs(Si=S) (A1), 200 1).
THE SYNTHESIS AND SOME PROPERTIES OF 1-THIA-3-SILACYCLOBUTANES AND 1-THIA-3-SILACYCLOPENTANE
Voronkov, M.G.,Kirpichenko, S.V.,Suslova, E.N.,Keiko, V.V.
, p. 13 - 19 (2007/10/02)
3,3-Dimethyl-1-thia-3-silacyclobutane has been obtained by the reaction of Me2Si(CH2Cl)2 with potassium hydrosulfide in abs. ethanol.Intramolecular hydrosilylation of isomeric vinylthioethyldiethylsilanes, HEt2Si-X-SCH=CH2 (X = CH(CH3) or CH2CH2) proceeds selectivity as α-addition to afford cyclic compounds, and , respectively.This ring closure reaction is catalyzed by (Ph3P)3RhCl.The endocyclic Si-C bond of 3,3-dimethyl-1-thia-3-silacyclobutane undergoes cleavage upon treatment with ethanolic KOH leading to Me2(EtO)SiCH2SCH3 and O(SiMe2CH2-SCH3)2.The reaction of 3,3-dimethyl-1-thia-3-silacyclobutane with ethanolic HgCl2 involves ring opening and formation of a complex, O2.
