4319-19-1Relevant articles and documents
Reactions of arenediazonium o-benzenedisulfonimides with aliphatic triorganoindium compounds
Barbero, Margherita,Cadamuro, Silvano,Dughera, Stefano,Ghigo, Giovanni
scheme or table, p. 862 - 868 (2009/04/11)
The reaction of various arenediazonium o-benzenedisulfonimides with aliphatic triorganoindium compounds is described. Surprisingly, with triethyl- or tributylindium we obtained N-ethyl- or N-butylanilines, respectively. This is the first case in which, at least formally, the reactive site of a diazonium salt is the nitrogen atom directly bonded to the aromatic ring. In contrast, with trimethylindium we obtained only formaldehyde (aryl)hydrazones. In order to explain the difference between trimethyl- and triethylindium we have proposed some reaction mechanisms, supported by detailed density functional (DFT) calculations. The possible role of diazene/hydrazone tautomerism initially assumed was discarded and therefore three mechanisms for the key step (nucleophilic addition of the trialkylindium to the N=N double bond of diazene) were studied. For the favoured mechanism there is a difference in the energy barriers of 2 kcalmol-1 between the reactions with trimethyl- and triethylindium. This difference is explained on the basis of the different C-In bond energies in the two organometallics and it is assumed to be enough to explain their different behaviour under the experimental conditions. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
Benzimidazole derivatives
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, (2008/06/13)
Disclosed are compounds represented by the following chemical formula (I) and pharmacologically acceptable salts thereof which are novel compounds useful as anticancer agents, antiviral agents or antimicrobial agents. STR1
Reductive N-monoalkylation of primary aromatic amines
Verardo,Giumanini,Strazzolini,Poiana
, p. 121 - 125 (2007/10/02)
Primary aromatic amines 1 with a variety of ring substituents are easily converted to their N-monoalkyl derivatives 3 by a simple variation of the sodium borohydride/sulfuric acid/carbonyl compound procedure previously described for their N-permethylations. The procedure is suitable for the α-minodeuterium labelling of the new N-substituent.
Synthesis and NMR-spectral characterization of N,N-dialkyl-3-nitroanilines, N,N-dialkyl-1,3-benzenediamines and their acyl derivatives
Katritzky, Alan R.,Rachwal, Bogumila,Rachwal, Stanislaw
, p. 337 - 345 (2007/10/02)
A recently discovered method for the synthesis of N,N-dialkyl-1,3-benzenediamines with two different alkyl groups is shown to be general.This is demonstrated by the synthesis of N-butyl-N-phenethyl-1,3-benzenediamine by the condensation of 3-nitroaniline with phenylacetaldehyde and benzotriazole, reduction of the adduct with sodium borohydride, acylation of the resulting N-phenethyl-3-nitroaniline with butyryl chloride, catalytic reduction of the nitro group by formic acid in the presence of triethylamine and palladium and finally reduction of the butyramide carbonyl group to the butyl substituent by lithium aluminium hydride.Several other routes were less efficient or failed completely.Classical methods for the synthesis of N,N-diethyl-1,3-benzenediamine were reexamined and improved.The recommended procedure involves alkylation of 3-nitroaniline with diethyl sulfate, trapping of N-ethyl-3-nitroaniline (by-product) by benzoylation, distillation of N,N-diethyl-3-nitro-aniline under reduced pressure and reduction of the nitro group by formic acid catalyzed by palladium.