- INDUSTRIAL PROCESS FOR THE PREPARATION OF N-ALKYL-N-TRIALKYLSILYLAMIDES
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The present invention relates to a process for producing N-alkyl-N- trialkylsilylamides from trialkylsilylhalides and N-alkylamides in the presence of a base and in the absence of a solvent.
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Page/Page column 12
(2012/10/18)
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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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- Multiple Reaction Channels of (N-Acyl-N-alkylcarbamoyl)oxyl Radicals from N-Acyl PTOC Carbamates
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N-Acyl-N-alkyl-N'-hydroxypyridine-2-thione carbamates (N-acyl PTOC carbamates) 1 are prepared in good to excellent yield by reactions of N-acylcarbamoyl chlorides with N-hydroxypyridine-2-thione sodium salt.Methods for production of the requisite carbamoyl chlorides by reaction of a secondary amide with trimethylsilyl triflate followed by treatment with phosgene were optimized.Precursors 1 react in radical chain reactions to give the title radicals (2) that can further react by several pathways.Decarboxylations of radicals 2 give amidyl radicals, and this method is excellent for production of acetamidyl radicals and in particular the N-methylacetamidyl radical which is difficult to prepare by other routes. 5-Exo cyclizations of amidyl radicals produced by decarboxylation of 2 give, ultimately, lactams and N-acylpyrrolidines. 1,5-Hydrogen transfer reactions of 2 to give α-amide radicals compete with decarboxylation; cyclization of an α-amide radical thus formed also is reported.The Lewis acid MgBr2 can reduce the 1,5-hydrogen atom transfer reaction apparently by a chelation effect on the precursor that leads to production of radical 2 in a conformation unfavorable for hydrogen atom transfer.By appropriate experimental design, radicals 2 often can be directed toward one desired reaction, and several relative rate constants for reactions of 2 necessary for such design were determined in this work.
- Esker, John L.,Newcomb, Martin
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p. 2779 - 2786
(2007/10/02)
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- SYNTHESIS OF N-(SILATRANYLMETHYL)-SUBSTITUTED LACTAMS AND CARBOXYLIC ACID AMIDES
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The general approach proposed for the synthesis of N-silatranylmethyl derivatives of lactams and carboxylic acid amides is based on the silyl variant of the akylation reaction.The treatment of N-trimethylsilyl-substituted lactams and carboxylic acid amides yielded N-trialkoxysilylmethyl lactam and amide derivatives.These were converted into the corresponding silatranes by the usual procedure (treating with triethanolamine in the presence of KOH).
- Kramarova, V.P.,Shipov, A.G.,Baukov, Yu.I.
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p. 2113 - 2119
(2007/10/02)
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- N'-ACYL-N-ALKYLCARBAMOYLOXY RADICALS: ENTRIES TO AMIDYL RADICALS BY DECARBOXYLATION AND TO α-AMIDE RADICALS BY RADICAL TRANSLOCATION
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N'-Acyl-N-hydroxypyridine-2-thione carbamates react in radical chain reactions to give the title radicals which can decarboxylate or react by intramolecular hydrogen atom transfer; the competing reaction pathways are controlled by the structure of the alkyl group and the conformation of the precursor which can be influenced by addition of a Lewis acid.
- Esker, John L.,Newcomb, Martin
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p. 5913 - 5916
(2007/10/02)
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