25445-76-5Relevant academic research and scientific papers
One-pot cyclizations of dilithiated oximes and hydrazones with epibromohydrin. Efficient synthesis of 6-hydroxymethyl-5,6-dihydro-4H-1,2- oxazines and oxazolo[3,4-b]pyridazin-7-ones
Dang, Tuan Thanh,Albrecht, Uwe,Gerwien, Katrin,Siebert, Melanie,Langer, Peter
, p. 2293 - 2301 (2007/10/03)
The one-pot cyclization of dilithiated oximes with epibromohydrin provided a convenient and regioselective approach to 6-hydroxymethyl-5,6-dihydro-4H-1,2- oxazines. The reaction of the latter with phosphorus tribromide resulted in a Beckmann rearrangement
Synthesis of lithium 1-alkynesulfenates by the mild oxidation of thiolates with a pinacolone-derived N-sulfonyloxaziridine
Sandrinelli, Franck,Boudou, Cédric,Caupène, Caroline,Averbuch-Pouchot, Marie-Thérèse,Perrio, Stéphane,Metzner, Patrick
, p. 3289 - 3293 (2008/09/18)
Lithium 1-alkynethiolates, generated by a base-induced ring cleavage of 4-substituted 1,2,3-thiadiazoles, were efficiently converted into the corresponding sulfenate salts by mild oxidation using an N-sulfonyloxaziridine derived from pinacolone. In situ S
Synthesis and reactions of haloazodienes. A new and general synthesis of substituted pyridazines
South, Michael S.,Jakuboski, Terri L.,Westmeyer, Mark D.,Daniel
, p. 8921 - 8934 (2007/10/03)
The reaction of dihalohydrazones with Hunig's base gives 1-carbethoxy-3-phenyl-4-haloazodienes in-situ, which were found to combine with a variety of electron rich olefins to yield halo-substituted tetrahydropynidazines. These haloazodiene cyclizations are best characterized as inverse electron demand, 4 + 2 hetero Diels-Alder reactions that maintain a high degree of regio- and stereochemical control. The chloro-substituted tetrahydropyridazines that are formed give high yields of substituted pyridazines upon treatment with base. The sequence of a chloroazodiene cyclization to a tetrahydropyridazine followed by an aromatization constitutes a new and general synthesis of substituted pyridazines. In contrast to the haloazodiene cyclizations, the novel cyclization reactions of the in-situ generated 1-carbethoxy-3-phenyl-4,4-dichloroazodiene were found to give N-aminopyrroles and pyridazines when combined with acyclic enamines. However, reactions with cyclic enamines gave the N-aminopyrroles, pyridazines, a dihydropyridazine as products as well as the noncyclized enamine intermediates. The noncyclized enamines could be converted to the N-aminopyrroles simply upon heating to higher temperatures, indicating a stepwise mechanism. The examples described here are the first reported cyclization reactions for dichloroazodienes.
Novel cyclization reactions of dichloroazodienes
South, Michael S.,Jakuboski, Terri L.,Westmeyer, Mark D.,Dukesherer, Daniel R.
, p. 1351 - 1354 (2007/10/03)
The novel cyclization reactions of the in-situ generated 1-carboxyethyl-3-phenyl-4,4-dichloroazodiene were found to give N-aminopyrroles and pyridazines when combined with acyclic enamines, Table 1. However, reactions with cyclic enamines gave the N-amino
Synthesis and reactions of chloroazodienes. A new and general synthesis of pyridazines
South, Michael S.,Jakuboski, Terri L.
, p. 5703 - 5706 (2007/10/02)
The reaction of dichlorohydrazones with Hunig's base gives 4-chloroazodienes, which were found to combine with a variety of electron rich olefins to yield chloro-substituted tetrahydropyridazines. These chloroazodiene cyclizations are best characterized a
Synthesis of 1,2,4-Triazolium Salts: Reaction of 1-Azo-2-azonia-allene Salts with Nitriles
Amer, A. M.
, p. 431 - 438 (2007/10/02)
Alkyl ketone hydrazones 1 are oxidized with tert-butylhypochlorite to give geminal chloro azo compounds 2.These react with SbCl5 to give 1-aza-2-azonia-allene salts 3 as reactive intermediates which are intercepted with nitriles to yield 3H-1,2,4-triazoli
Electrosynthesis of (E)-Ethenyl-O-ethyl-thiocarbonates
Hess, U.,Schulze, M.
, p. 901 - 908 (2007/10/02)
Electrochemical reductions of 4-aryl- and 4,5-diaryl-1,2,3-thiadiazols (1-5) in acetonitrile/0,1 M tetraalkylammonium-supporting-electrolyte at Hg-cathodes in the presence of ethylchloroformiate (CAE) yield (E)-S-(2-aryl) ethenyl- and S-(1,2-diaryl)etheny
