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1.
E. Sh. Finkel'shtein N. V. Ushakov N. A. Pritula E. A. Andreev N. A. Platé 《Russian Chemical Bulletin》1992,41(1):185-187
The thermally initiated and platinum-catalyzed polymerization of 1-silacyclobutanes with substitutents containing a trimethylsilyl group was carried out. Soluble, high-molecular-weight, heterochain siltrimethylene polymers were obtained, containing trimethylsilyl groups removed from the main chain by various bridges.A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 117912 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 223–225, January, 1992. 相似文献
2.
Preparation and Molecular Structures of Oligofunctional Dirhenium Carbonyl Derivatives from Dirhenium Nonacarbonylphosphane Starting with dirheniumdecacarbonyl, one CO-Ligand was eliminated oxidatively and substituted by the labile acetonitrile ligand. As an intermediate eq-Re2(CO)9NCCH3 was received. The reaction of this labilised carbonyl with tris(trimethylsilyl)phosphine and subsequent methanolysis gave ax-Re2(CO)9PH3, which was isolated and characterized for the first time. Photochemical and thermal reaction of ax-Re2(CO)9PH3 led to the new bi- and trinuclear complexes Re2(μ-H)(μ3-PHRe(CO)5)(CO)8, Re2(μ-PH2)2(CO)8 and Re2(μ-H) · (μ-PH2)(CO)8, which were characterized by IR-, 1H- and 31P-NMR spectroscopy. The structures of ax-Re2(CO)9PH3, Re2(μ-H)(μ3-PHRe(CO)5)(CO)8 and Re2(μ-PH2)2(CO)8 were confirmed by single-crystal X-ray analysis. ax-Re2(CO)9PH3 has a very short Re? P bond length of 228(2) pm. 相似文献
3.
WONG Henry N. C. 《中国化学》2005,23(8):1106-1108
Trimethylsilyl groups have been used in our research as a director as well as a bulky and lipophilic group in our quest for natural and non-natural molecules. 相似文献
4.
Mohammad Ali Zolfigol Iraj Mohammadpoor-BaltorkDavood Habibi BiBi Fatemeh MirjaliliAbdolhamid Bamoniri 《Tetrahedron letters》2003,44(44):8165-8167
Primary and secondary trimethylsilyl ethers were converted to their corresponding ethers in the presence Nafion-H® with good to excellent yields under mild and heterogeneous conditions. 相似文献
5.
Nils Wiberg 《Angewandte Chemie (International ed. in English)》1971,10(6):374-387
The highly reactive compound bis(trimethylsilyl)diimine (BSD), which was first prepared by oxidation of lithium tris(trimethylsilyl)hydrazide, is light blue, sensitive to thermolysis and hydrolysis, and ignites spontaneously in air. On the basis of electron transfer, acid-base, or free-radical reactions, it acts in particular as a (preparatively useful) redox system and as an agent for the introduction of azo groups. Redox reactions lead by oxidation or reduction of the other reactant through two oxidation stages to hydrazine derivatives or molecular nitrogen, and in the case of electrochemical reduction, to BSD radical-anions. Azo-group transfers, on the other hand, yield new inorganic azo compounds with no change in the oxidation state of the diimine group. 相似文献
6.
A four-step synthesis of 1-(-ydroxyalkyl)- and 1-(4-hydroxyphenyl)silacyclobutanes was carried out. The influence of the structure of the initial compounds and the reaction conditions on the ratio of the reaction products formed was studied. The stability of the silacyclobutane alcohols and the hydrolysis of their trimethylsilyl ethers were investigated.For preliminary communication, see Ref. 6.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 946–954, April, 1996. 相似文献
7.
Silyl stabilized azanes: reactions of lithiumbis(trimethylsilyl)hydrazine with trialkyltin halides 总被引:1,自引:0,他引:1
Lithium 1,2-bis(trimethylsilyl)hydrazine (1a) reacts with Me3SnCl, Et3SnBr and Bu3SnCl to form bis(trimethylsilyl)(trimethylstannyl)hydrazine (2a), (triethylstannyl)bis(trimethyl silyl)hydrazine (2b) and (tributylstannyl)bis(trimethylsilyl)hydrazine (2c), respectively. Compounds 2a and 2b undergo disproportionation at room temperature to form bis(trimethylsilyl)bis(trimethylstannyl)hydrazine (3a) and bis(triethylstannyl)bis(trimethylsilyl)hydrazine (3b). In contrast, 2c is highly stable and can withstand such a reaction up to 150 °C. The monostannylated products, 2a, 2b and 2c do not get lithiated at NH and instead undergo transmetallation in their reaction with RLi or Li to form lithiumbis(trimethylsilyl)hydrazine (1a). 相似文献
8.
9.
The first synthesis of the fungal natural product (−)-xylariamide A 1 is reported. N,O-Bis(trimethylsilyl)acetamide induced coupling of d-tyrosine with (E)-but-2-enedioic acid 2,5-dioxo-pyrrolidin-1-yl ester methyl ester 5 produced the dechloro natural product 6, which was subsequently monochlorinated using oxone and KCl to yield synthetic 1. (−)-Xylariamide A 1, (+)-xylariamide A 2 and (−)-dechloroxylariamide A 6 displayed no cytotoxic or antimicrobial activity. 相似文献
10.
Surface modification of poly [1-(trimethylsilyl)-1-propyne] (PTMSP) membranes bybromine vapor has been studied. It is shown that Br/C atomic ratio at the surfaces increased withthe time of bromination until about 60 min, then it reached a plateau. The results of XPS and IRstudies indicated that the addition of bromine to double bonds and the replacement of H on CH_3 bybromine had taken place so that a new peak at 286.0 eV (C--Br)in C_(1s) spectra and some newbands, e. g. at 1220 and 580cm~(-1) in IR spectra were formed. The fact,t Po_2, permeability ofoxygen, decreased and α_(O_2/N_2), separation factor of oxygen relative to nitrogen, increased withbromination time, shows that surface modification of PTMSP by bromine may be an efficient approach to prepare PTMSP membranes used for practical gas separations. 相似文献