New quinoline and pyrazole derivatives are obtained after the acid-promoted intramolecular rearrangement of regioisomeric pyrazolines resulting from the cycloaddition of 6,6-diphenylpentafulvene with diarylnitrilimines.
KETOKEN GEM-DITHIOLS AND TRITHIONES: SYNTHESIS AND STUDY OF THE BEHAVIOR TOWARDS DIPOLE REAGENTS; SYNTHESIS OF SOME NITROGEN HETEROAROMATICS
作者:Salem E. Zayed
DOI:10.1080/10426509608029632
日期:1996.1.1
Abstract The behavior of ketoken gem-dithiols towards active methylene and methyl groups resulted in the formation of thiopyrano-dihydrocaumarine derivatives IIIa, b via cyclocondensation reaction between substituted 4-dihydrocyclohexanone Ia, b. N-phenylpyrazoline derivative VI was also formed through reaction of gem-dithiol IV with malonic acid followed by phenyl hydrazine. Pyridopyridazine derivative
摘要 酮基二硫醇对活性亚甲基和甲基的行为导致通过取代的 4-二氢环己酮 Ia、b 之间的环缩合反应形成噻吩并二氢黄豆素衍生物 IIIa、b。N-苯基吡唑啉衍生物VI也通过偕二硫醇IV与丙二酸和苯肼反应形成。还可以合成吡啶并哒嗪衍生物XII。还研究了 XV 中硫酮基团对某些偶极系统的行为,以得到螺产物 XVIII-XX。
Chemodivergent annulations of allenyl imides and β,γ-enones switched by nucleophilic phosphine and amine catalysts
chemodivergent [4 + 1] and [3 + 3] annulations of allenyl imides and β,γ-enones have been developed, furnishing highly substituted 2-cyclopentenone and 2-pyranone derivatives in moderate to excellent yields. Two plausible reaction mechanisms involving two different ketene intermediates have been proposed to explain the observed chemoselectivity. Moreover, by virtue of the α,β-enone substructure of the [4 + 1]