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31.
Giuliana Pitacco Orazio A. Attanasi Lucia De Crescentini Gianfranco Favi Fulvia Felluga Cristina Forzato Fabio Mantellini Patrizia Nitti Ennio Valentin Ennio Zangrando 《Tetrahedron: Asymmetry》2010,21(5):617-622
Chiral non-racemic 1,4-dihydropyridazines were prepared by the reaction of 1,2-diaza-1,3-dienes with arylacetaldehydes under organocatalytic conditions. l-Proline and (S)-(+)-1-(2-pyrrolidinylmethyl)pyrrolidine coupled with trifluoroacetic acid were used as organocatalysts. Enantiomeric excesses ranged from 25% to 78%. 相似文献
32.
3-n-Pentadecylphenol (hydrogenated cardanol) and its derivative 5-n-pentadecyl-2-tert-butylphenol can be nitrated using nitric acid in acetonitrile or methanol to give mono, di or trinitro products. 5-n-Pentadecyl-2-nitrophenol undergoes reductive carbonylation to give a benzoxazole-2-one derivative. An efficient catalytic oxidation reaction in the presence of MeReO3 has also been studied. 相似文献
33.
Orazio A. Attanasi Silvia Bartoccini Gianluca Giorgi Fabio Mantellini Francesca R. Perrulli Stefania Santeusanio 《Tetrahedron》2010,66(27-28):5121-5129
Depending on the nature of the solvent, alcohol or DMF, N-phenylbenzamidine shows different nucleophilic behaviour towards the conjugated azo–ene system of 1,2-diaza-1,3-dienes. In alcohol it reacts as a nucleophile through the N-phenyl imino nitrogen affording spiro pyrroloimidazoles and 1,3-diphenyl-1H-imidazoles. In DMF, by contrast, it behaves as nucleophile mainly by means of the imino amidino nitrogen providing 2-phenylimidazole derivatives by loss of the aniline molecule. 相似文献
34.
Attanasi OA Davoli P Favi G Filippone P Forni A Moscatelli G Prati F 《Organic letters》2007,9(17):3461-3464
Michael-type addition of aziridinecarboxylates to 1,2-diaza-1,3-butadienes under solvent-free conditions (SFC) resulted in the formation of alpha-aziridinohydrazone adducts. In toluene under reflux, alpha-aziridinohydrazones gave imidazoles in moderate to good yields. Such a reactivity pattern is explained by 1,5-electrocyclization of azavinyl azomethine ylide generated through thermal ring opening of alpha-aziridinohydrazones. 相似文献
35.
OrazioA. Attanasi Lucia DeCrescentini Paolino Filippone Fabio Mantellini Stefania Santeusanio 《Helvetica chimica acta》2001,84(8):2379-2386
3‐{[(tert‐Butoxy)carbonyl]diazenyl}but‐2‐enoates react in tetrahydrofuran at room temperature with aromatic 1,2‐diamines to give 3‐methylquinoxaline‐2‐carboxylates. These products were also obtained in solid‐phase synthesis, by using polymer‐bound 3‐diazenylbut‐2‐enes. 相似文献
36.
Orazio A. Attanasi Gianfranco Favi Cristina Forzato Stefano Morganti Giuliana Pitacco Domenico Spinelli 《Tetrahedron》2006,62(26):6420-6434
A study of the behaviour of some electron-rich 2-methyleneindolines (1-3) with different electron-poor reagents (formation of new carbon-carbon and nitrogen-carbon bonds) has furnished interesting results from both synthetic and the mechanistic viewpoints. Enamines 1-3 have been reacted with the β-nitroenamines 4-7 (reaction CeCl3·7H2O promoted), giving the polymethine dyes 14-23. The same bases 1-3 have been nitroalkylated with the nitroolefins 8-10, furnishing the indolines 24-32, and the diastereoselectivity of the reaction has been thoroughly investigated. The most unexpected results derived from the first example of reaction of Fischer's bases with 1,2-diaza-1,3-butadienes. In fact, with 11-13, the ‘unknown’ indoline spirodihydropyrroles 33-40 were formed. Their structures were unambiguously assigned, and we determined, as an example, that of 33 by X-ray analysis. 相似文献
37.
Orazio A. Attanasi Paolino Filippone Amedeo Mei Francesca Romana Perrulli Franco Serra-zanetti 《合成通讯》2013,43(11):1411-1421
Pyrrole and several its derivatives have been subjected to extensive chemical investigations, while substituted 1-aminopyrroles remain a class of compounds about which relatively little is known due to the far from trivial problem sposed by their syntheis. In fact, 1-aminopyrroles appear to be prepared mainly by direct reactionfrom conjugated azoalkenes,2 that unfortunately represent a class of relatively little 相似文献
38.
Attanasi OA De Crescentini L Favi G Nicolini S Perrulli FR Santeusanio S 《Organic letters》2011,13(3):353-355
1,2-Diaza-1,3-dienes (DDs) react as Michael acceptors with primary amines to afford α-aminohydrazone derivatives that were in situ coupled with isocyanates. Intramolecular ring closure of the asymmetric urea derivatives so formed allows for a selectively substituted hydantoin ring to be obtained. The hydrazone side chain introduced by the conjugated heterodiene system at the 5-position of the heterocycle represents a valuable functionality for accessing novel 5-acyl derivatives difficult to obtain by other methods. 相似文献
39.
Antonio ArcadiOrazio A. Attanasi Gianluca GiorgiPaolino Filippone Elisabetta RossiStefania Santeusanio 《Tetrahedron letters》2003,44(46):8391-8394
1,2-Diaza-1,3-butadienes reacted with rhodanine affording 2-(mercaptoacetyl)iminothiazoline derivatives through conjugate addition/annulation/ring-opening/oxidative dimerization. The hypothesized ring-closure and ring-opening mechanism was supported by X-ray crystal structure analysis of a compound obtained by reaction of the same reagents with a chiral 1,3-oxazolidine-2-thione derivative. 相似文献
40.
Attanasi OA De Crescentini L Favi G Mantellini F Nicolini S 《The Journal of organic chemistry》2011,76(20):8320-8328
A novel and simple one-pot synthesis of 3-substituted 2,5,6,7-tetrahydro-1H-1,4-diazepin-2-ones from 1,2-diaza-1,3-dienes (DDs) and N-unsubstituted aliphatic 1,3-diamines is described. Here we also report a procedure to selectively obtain alkyl 5H-1,4-benzodiazepine-3-carboxylates from the DDs and 2-aminobenzylamine. Both processes occur by means of sequential 1,4-conjugated addition followed by regioselective 7-exo cyclization. The behavior of N-methyl- and N,N'-dimethyl-1,3-diaminopropanes toward the DDs furnished pyrazol-3-ones and bis-α-aminohydrazones, respectively. 相似文献