Synthesis of a Polycyclic .PI.-Conjugated System Containing an Azulene Unit by the Flash Vacuum Pyrolytic Method. IV. Synthesis and Properties of 1-Isopropylidene-1H- and 3-Isopropylidene-3H-cyclopent(a)azulene.
A new π-conjugated system, 1-isopropylidene-1H-cyclopent[a]azulene was synthesized by the base-catalyzed condensation of 1H-cyclopent[a]azulene with acetone. An isomeric 3-isopropylidene-3H-cyclopent[a]azulene was also synthesized by the reaction of 3H-cyclopent[a]azulen-3-one with dimethylketene. The condensation of fulvene did not perturb the properties of the azulene moiety as shown by the spectral data. The X-ray analysis of 3-isopropylidene-3H-cyclopent[a]azulene also indicated that this π-conjugated system was an azulene moiety slightly perturbed by the fused fulvene ring.
在碱催化下,1H-环戊并[a]氮烯与丙酮缩合,合成了一种新的π-共轭体系--1-异亚丙基-1H-环戊并[a]氮烯。通过 3H-环戊并[a]氮烯-3-酮与二甲基乙烯的反应,还合成了异构体 3-异亚丙基-3H-环戊并[a]氮烯。光谱数据显示,富烯的缩合并没有扰乱薁分子的性质。对 3-isopropylidene-3H-cyclopent[a]azulene 的 X 射线分析也表明,这种 π 共轭体系是一种受融合富烯环轻微扰动的薁分子。
The Synthesis and Properties of Cyclopent[a]azulen-3(H)-one
π-conjugated system, cyclopent[a]azulen-3(H)-one, was prepared by flash vacuum pyrolysis on the final step. All proton signals of this molecule were observed at higher magnetic resonance field than expected in terms of induced paramagneticringcurrent in the periphery of this molecule.
Synthesis of a Polycyclic π-Conjugated System Containing an Azulene Unit by the Flash Vacuum Pyrolytic Method. II. Synthesis and Paratropic Properties of 3<i>H</i>-Cyclopent[<i>a</i>]azulen-3-one and Its Methyl Derivatives
3H-Cyclopent[a]azulen-3-one and two methyl derivalives, which have a new tricyclic π-conjugated system, were synthesized starting from 9-methoxycarbonyl-1,2-dihydro-3H-cyclopent[a]azulen-3-one by the application of flash vacuum pyrolysis in the final step. All proton signals of these compounds were observed at higher fields than those of the referenced 1,2-dihydro compound, but there are no significant