Von kleinen Bausteinen zu neuen Poly‐alkoxo‐oxometallat‐Derivaten: Synthese und Strukturaufklärung von K4[VIV12O12(OCH3)16(C4O4)6], Cs10[VIV24O24(OCH3)32(C4O4)12][VIV8O8(OCH3)16(C2O4)] und M2[VIV8O8(OCH3)16(VIVOF4)] (M = [N(nBu)4] bzw. [NEt4])

>From Small Fragments to New Poly‐alkoxo‐oxo‐metalate Derivatives: Syntheses and Crystal Structures of K₄V^IV₁₂O₁₂(OCH₃)₁₆(C₄O₄)₆], Cs₁₀V^IV₂₄O₂₄(OCH₃)₃₂(C₄O₄)₁₂]V^IV₈O₈(OCH₃)₁₆(C₂O₄)], and M₂V^IV₈O₈(OCH₃)₁₆(V^IVOF₄)] (M = N(nBu)₄] or NEt₄]) By solvothermal reaction of ortho‐vanadicacid ester VO(OMe)₃] with squaric acid and potassium or caesium hydroxide the compounds K₄V^IV₁₂O₁₂(OCH₃)₁₆(C₄O₄)₆] ( 2 ) and Cs₁₀V^IV₂₄O₂₄(OCH₃)₃₂(C₄O₄)₁₂]V^IV₈O₈(OCH₃)₁₆(C₂O₄)] ( 3 ) could be syntesized. With tetra‐n‐butyl‐ or tetra‐n‐ethylammonium fluoride N(nBu)₄]₂V^IV₈O₈(OCH₃)₁₆(V^IVOF₄)] ( 4 ) and N(Et)₄]₂V^IV₈O₈(OCH₃)₁₆(V^IVOF₄)] ( 5 ) could be isolated. In 2 and 3 the corners of a tetrahedron or cube resp. are occupied by {(VO)₃(OMe)₄} groups and connected along the edges of the tetrahedron resp. cube by six or twelve resp. squarato‐groups. The octanuclear anions in the compounds 3 , 4 , and 5 are assumedly built up by fragments of the ortho‐vanadicacid ester VO(OMe)₃]. Around the anions C₂O₄^2— or VOF₄^— these oligormeric chains are closed to a ring . Crystal data: 2 , tetragonal, P4₃, a = 18.166(3)Å, c = 29.165(7)Å, V = 9625(3)ų, Z = 4, d_c = 1.469 gcm^—3; 3 , orthorhombic, Pbca, a = 29.493(5)Å, b = 25.564(4)Å, c = 31.076Å, V = 23430(6)ų, Z = 4, d_c = 1.892 gcm^—3; 4 , monoclinic, P2₁/n, a = 9.528(1)Å, b = 23.021(2)Å, c = 19.303(2)Å, β = 92.570(2)°, V = 4229.8(5)ų, Z = 2, d_c = 1.391 gcm^—3; 5 , monoclinic, P2₁/n, a = 16.451(2)Å, b = 8.806(1)Å, c = 23.812(1)Å, β = 102.423(2)°, V = 3368.7(6)ų, Z = 2, d_c = 1.534 gcm^—3.