Syntheses of an isoannelated annulene,a bisdehydro[14]annuleno[c]furan and bisdehydro[14]annulene derivatives

A bisdehydro[14]annuleno[c]furan, an isoannelated diatropic annulene, has been synthesized. Cyclic glycol, a precursor of the annuleno[c]furan, could be converted into bisdehydro[14]annulene derivatives under mild acidic conditions.     

Trisdehydro[14]annuleno[16]annulene

Trisdehydro[14]annuleno[16]annulene consisting of an aromatic bisdehydro[14]annulene and an antiaromatic bisdehydro[16]annulene has been synthesized. The strong paratropicity was observed in the [16]annulene moiety being comparable with that of extremely unstable parent bisdehydro[16]annulene.     

Tetrakisdehydro[14]annuleno[16]annulene

Tetrakisdehydro[14]annuleno[16]annulene consisting of an aromatic bisdehydro[14]-annulene and an antiaromatic trisdehydro[16]annulene has been synthesized. The ¹H NMR parameters clearly indicate the strong paratropicity and diatropicity of the 16-membered and 14-membered rings, respectively.     

Tetrakisdehydro[14]annuleno[20]annulene

Tetrakisdehydro[14]annuleno[20]annulene consisting of an aromatic bisdehydro[14]annulene and an antiaromatic trisdehydro[20]annulene has been synthesized. The ¹H NHR spectra clearly indicate the induction of para- and diamagnetic ring currents in each of the [4n]- and [4n+2]-rings, respectively.     

An ortho-fused tetrakisdehydro[14]annuleno[14]annulene consisting of two different types of bisdehydro[14]annulenes

Tetrakisdehydro[14]annuleno[14]annulene consisting of ‘acetylene-cumulene’ bisdehydro[14]annulene and Sondheimer's bishydro[14]annulene has been synthesized. It was found that a strong diatropicity was observed in the ‘acetylene-cumulene’ bisdehydro[14]annulene moiety, whereas diatropicity of another bisdehydro[14]annulene moiety shows marked decrease comparable with that of napthobisdehydro[14]annulene synthesized by Sondheimer.     

Neue Vertreter des K2Li14[Pb3O14]-Typs Cs2Li14[Tb3O14] und K2Li14[Zr3O14] [1, 2]

Inhaltsübersicht. Erstmals wurden klar durchscheinende, orange-farbene Einkristalle von Cs₂Li₁₄[Tb₃O₁₄] aus Cs₂TbO₃ und Li₂O (Tb: Li = 1:5) dargestellt [550°C, 21 d, verschlossenes AuRohr]. Es liegt der K₂Li₁₄[Pb₃O₁₄]-Typ vor [Vierkreisdiffraktometerdaten, PW 1100, MoKä-Strahlung, 660 I_o(hkl), R = 4,8%, R_w = 3,4%, Immm, a = 1293,5(8), b = 792,6(3), c = 740,4(3) pm, Z = 2, d_rö = 4,65]. Ebenfalls neu wurde K₂Li₁₄[Zr₃O₁₄] in Form farbloser Einkristalle durch Tempern inniger Gemenge von K₂O, Li₂O und ZrO₂ (K: Li: Zr = 1:4:1,5) dargestellt [900°C, 14 d, geschlossene Ni-Bombe] und röntgenographisch untersucht. Die Strukturverfeinerung [612 I_o(hkl), Vierkreisdiffraktometerdaten, PW 1100, MoKα-Strahlung, R = 5,9%, R_w = 5,3%, Immm, a = 1244,6, b = 776,4, c = 724,3 pm, Z = 2] bestätigt die Isotypie mit K₂Li₁₄[Pb₃O₁₄]. Der Madelunganteil der Gitterenergie, MAPLE, Effektive Koordinationszahlen, ECoN, diese über Mittlere Effektive Ionenradien, MEFIR, wurden berechnet. Für die nun bekannten Vertreter dieses Typs wurde ein Isotypievergleich vorgenommen. New Compounds of the K₂Li₁₄[Pb₃O₁₄] Type: Cs₂Li₁₄[Tb₈O₁₄] and K₂Li₁₄[Zr₃O₁₄] For the first time Cs₂Li₁₄[Tb₃O₁₄] has been prepared as orange single crystals from Cs₂TbO₃ and Li₂O (Tb: Li = 1:5) [550°C, 21 d, sealed Au-Tube]. Structure Refinement [four-circle diffractometer data, PW 1100, MoKα radiation, 660 I_o(hkl), R = 4.8%, R_w = 3.4%, Immm, a = 1293.5(8), b = 792.6(3), c = 740.4(3) pm, Z = 2, d_rö = 4.65] confirms isotypy with K₂Li₁₄[Pb₃O₁₄]. K₂Li₁₄[Zr₃O₁₄] has also been prepared as colorless single crystals from K₂O, Li₂O, and ZrO₂ (K: Li: Zr = 1:4:1.5), [900°C, 14 d, closed Ni-cylinder] and investigated by x-ray [612 I_o(hkl), four-circle diffractometer data, PW 1100, MoKα radiation, R = 5.9%, R_w = 5.3%, Immm, a = 1244.6, b = 776.4, c = 724.3 pm, Z = 2]. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, the latter derived from Mean Effective Fictive Ionic Radii, MEFIR, are calculated. A detailed comparison of the structures is carried out.