Regioselective synthesis of polysubstituted 3,3′-bi-1H-pyrazole derivatives via 1,3-dipolar cycloaddition reactions
作者:Ahmad M. Farag、Nabila A. Kheder、Milos Budesinsky
DOI:10.1016/s0040-4020(97)00583-8
日期:1997.7
add regioselectively to α-(benzothiazol-2-yl)cinnamonitriles 3 and α-(1-methylbenzimidazol-2-yl)cinnamonitriles 7 to yield exclusively the cycloadducts 5,5′-dicyano-4,4′,5,5′-tetrahydro[3,3′-bi-1H-pyrazoles] 4 and 8, respectively. Compounds 4 and 8 undergo aromatization via thermal elimination of hydrogen cyanide under basic conditions to afford the corresponding 3,3′-bi-1H-pyrazole derivatives 6 and
Ghoneim, K. M.; El-Basil, S.; Osman, A. N., Revue Roumaine de Chimie, 1991, vol. 36, # 11-12, p. 1355 - 1362
作者:Ghoneim, K. M.、El-Basil, S.、Osman, A. N.、Said, M. M.、Megahed, S. A.
DOI:——
日期:——
Microwave-assisted synthesis under solvent-free conditions of (E)-2-(Benzo[d]thiazol-2-yl)-3-arylacrylonitriles
作者:Jorge E. Trilleras、Kelly J. Velasquez、Dency J. Pacheco、Jairo Quiroga、Alejandro Ortíz
DOI:10.1590/s0103-50532011001200022
日期:——
A series of (E)-2-(benzo[d]thiazol-2-yl)-3-arylacrylonitriles was synthesized by microwave assisted Knoevenagel condensation under solvent-free conditions from the corresponding 2-(benzo[d]thiazol-2-yl) acetonitrile and aromatic aldehydes with electrondonating/electron-withdrawing groups. The reaction times were considerably short and the products obtained in moderate yields (50 to 75%) and good purity. The configuration of the acrylonitrile double bond could not be established by regular NMR methods. However, theoretical studies suggest that the E isomer is more stable than Z, which is in good agreement with some experimental evidences.
Farag Ahmad M., Abbas Ikhlas M., Abdallah Magda A., Kandeel Zaghloul E., +, J. Chem. Res. Synop, (1994) N 7, S 286-287
作者:Farag Ahmad M., Abbas Ikhlas M., Abdallah Magda A., Kandeel Zaghloul E., +