- Unusual course of diazolees silylation and N-siloxycarbonylation
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The N-siloxycarbonylation and transamination reactions were studied by an example of diazoles. We found that because of insufficient nucleophilicity of the nitrogen atoms in the first case only the sililylation process occurs, in the second case the low-boiling amine is replaced by the higher boiling one and the process is completed by the formation of O-silyluretans. Pleiades Publishing, Ltd., 2011.
- Kirilin,Belova,Pletneva,Panfilova,Storozhenko,Sheludyakov
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experimental part
p. 1493 - 1495
(2011/10/18)
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- Organosilicon synthesis of isocyanates: III. Synthesis of aliphatic, carbocyclic, aromatic, and alkylaromatic isocyanatocatboxylic acid esters
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A series of aminoacid esters was prepared by treating the aminoacid suspensions in ethanol with thionyl chloride. Best conversion of aminoacid esters to corresponding isocyanates was achieved in the case of aromatic and carbocyclic aminoesters by phosgeneation of their N-silyl derivatives, and in the case of aliphatic and alkylaromatic aminoesters by phosgeneation of O-silyl or N,O-bissilylurethanes on their basis. In the last case additional step of esterification of the by-products isocyanatoalkylcarboxylic acid chlorides is required after phosgeneation. Unusual generation of cynnamates and intramolecular N→O-migration of trimethylsilyl group in the solutions of silylated alkylaromatic β-aminoacid esters were found. Pleiades Publishing, Inc., 2006.
- Lebedev,Lebedeva,Sheludyakov,Ovcharuk,Kovaleva,Ustinova
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p. 1069 - 1080
(2008/02/05)
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- Carbacephalosporin compound, their preparation and use
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Carbacephalosporin compounds of formula (I), STR1 salts thereof, processes for their synthesis and uses thereof, wherein: R1 is hydrogen, methoxy or formamido; R2 is an acyl group; CO2 R3 is a carboxy group or a carboxylate anion, or R3 is a carboxy protecting group or a pharmaceutically acceptable salt-forming group or in vivo hydrolysable ester group; R4, R5, R6 and R7 represent hydrogen or a substituent; R4 and R7 may be replaced by a chemical bond between the two carbon atoms shown; R5 and R6 may be linked together into a cyclic system. The compounds (I) have antibacterial properties.
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- The reaction of chloromethylsilanes with amines, hexamethyldisilazanes, and silylcarbamates
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The reactions of chloromethylsilanes with amines, hexamethyldisilazane, and silylcarbamates were studied.The dependence of the composition and structure of the resulting products on the nature of the reagents used and reaction conditions was determined.A scheme for the synthesis of 4,9-diaza-2,7-dioxa-1,6-disilacyclodecane-3,8-dione derivatives was suggested. - Key words: synthesis, chloromethylsilanes, silylcarbamates, hexamethyldisilazane, transsilylation and silicomethylation.
- Kirilin, A. D.,Sokova, N. B.,Chernyshev, E. A.
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p. 1703 - 1706
(2007/10/02)
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- Homogeneous Catalytic Formation of Carbon-Nitrogen Bonds. 2. Catalytic Activation of the Silicon-Nitrogen Bond
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The catalytic formation of new carbon-nitrogen single bonds can be promoted via catalytic activation of silicon-nitrogen bonds.Silazanes, compounds containing Si-N bonds, will react, in the presence of a catalyst, with compounds containing carbon-oxygen double bonds to form new C-N and Si-O bonds concurrently.Thus, CO2 and phenyl isocyanate can be reacted with a number of silazane compounds to give urethane and urea derivatives in 60-90percent yields.In the absence of catalysts, the identical reactions either do not proceed or go to less than 20percent conversion.Aldehydes and ketones also react in a similar manner to give imines and enamines, respectively.A variety of group 8 metals have been found to activate the Si-N bond in the catalytic formation of PhCH=NPh from PhNHSiM3 and PhCHO.Iron and rhodium catalysts were found to be the most active for this reaction.The catalytic activation of Si-N bonds was also found useful in the ring-opening oligomerization of in the presence of (Me3Si)2NH.
- Zoeckler, M. T.,Laine, R. M.
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p. 2539 - 2543
(2007/10/02)
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