109988-48-9Relevant academic research and scientific papers
Reaction of Oxazoles. Formation of Abnormal Diels-Alder Adducts of 5-Methoxy-4-(p-nitrophenyl)oxazoles with Tetracyanoethylene, and X-Ray Crystal Structure of One of the Products
Ibata, Toshikazu,Isogami, Yasushi,Nakano, Shuji,Nakawa, Hiroyuki,Tamura, Hatsue
, p. 1692 - 1693 (1986)
The reaction of 2-alkyl or -aryl substituted 5-metoxy-4-(p-nitrophenyl)oxazoles (1) with tetracyanoethylene gave 2-substituted methyl 3,3,4,4-tetracyano-5-(p-nitrophenyl)-4,5-dihydro-3H-pyrrole-5-carboxylates (2) as formal cycloadducts; these were produced via a zwitterionic mechanism involving oxazole ring opening.
Abnormal Diels-Alder Reaction of 5-Alkoxyoxazoles with Tetracyanoethylene and X-Ray Crystal Structure of an Adduct
Ibata, Toshikazu,Isogami, Yasushi,Nakawa, Hiroyuki,Tamura, Hatsue
, p. 1771 - 1778 (2007/10/02)
The reaction of 2-alkyl- or 2-aryl-substituted 5-methoxy-4-(p-nitrophenyl)oxazoles with tetracyanoethylene gave methyl esters of 5-substituted 3,3,4,4-tetracyano-2-(p-nitrophenyl)-3,4-dihydro-2H-pyrrole-2-carboxylic acid as formal cycloadducts through oxazole ring opening.Zwitterionic mechanisms were proposed on the basis of the solvent effect on the reaction.The molecular structure of 2-isopropyl-substituted product was determined by means of X-ray crystallography.Crystals of the cycloadduct are orthorhombic with space group Pcab having unit-cell dimensions of a=17.998(2), b=27.188(6), c=15.833(3) Angstroem, and Z=16, which contains two crystallographically independent molecules.The final R value is 0.070 for 4629 observed reflections.
