Potassium diphthalocyaninato(2±)metallate(III), K[M(pc 2± ) 2 ] (M = Bi, La, Ce, Pr, Sm, Sb, In) has been prepared by melting the metal chloride, iodide or acetate with 1,2-dicyanobenzene in the presence of potassium methylate. Crystallisation with tetra(n-butyl)ammonium bromide or hydroxide (( n Bu 4 N)Br/OH), tetra(n-pentyl)ammonium chloride (( n Pe 4 N)Cl) or bis(triphenylphosphine)iminium halide ((PNP)X; X = Br, I) yields the corresponding red-purple complex salt ( n Bu 4 N)[M(pc 2± ) 2 ] (M = Bi (1), La (3), Ce (2)), ( n Bu 4 N)[M(pc 2± ) 2 ]´x CH 3 OH (M = Bi (5), Pr (6), Sm (7); 0 9 x 9 1), ( n Pe 4 N)[La(pc 2± ) 2 ] (4), ( n Bu 4 N)[Pr(pc 2± ) 2 ]´2 py (10), ( n Bu 4 N)[Sb(pc 2± ) 2 ]´2 thf (11), (PNP) 2 [M(pc 2± ) 2 ]Br2 Et 2 O (M = Sb (12), Bi (13)), and (PNP) 2 [In(pc 2± ) 2 ]I´2 Et 2 O (14). Bronze coloured diphthalocyaninato(1±)metal(III) polyiodide, [M(pc ± ) 2 ]I 2 (M = Sc, Y) has been prepared similarly in the presence of ammonium iodide. Reduction with ( n Bu 4 N)OH provides ( n Bu 4 N)[M(pc 2± ) 2 ]´x CH 3 OH (M = Y (8), Sc (9); 0 9 x 9 1). Spectral properties (UV/VIS/NIR; IR; resonance Raman) of diphthalocyaninates in their different ring oxidation states (2±/2±; 2±/1±; 1±/1±) are discussed. 1±3 crystallise in the tetragonal (P4/ncc), 5±9 in the orthorhombic (Pna2 1 ), 10, 11 in the triclinic (P-1), and 4, 12± 14 in the monoclinic crystal system (4: P2 1 /m; 12: C2/c; 13, 14: P2/c). Ecliptic rotamers with skew angles ranging from 4.1°to 6.0°are found in 1±3, and staggered rotamers with skew angles ranging from 35.8°to 45.0°are found in 4±14. The mean M±N i bond lengths and interplanar distances increase monotonically with the ionic radius of the metal ion. Both distances deviate notably from this linear correlation in the Sb III and Bi III derivatives. The discrepancy is presumably due to the sterical dominance of the ns 2 lone-pair character. The actual size of eight co-ordinated Sb III and Bi III is estimated to be R 8 » 1.02(Sb)/1.11(Bi) A Ê . In every complex salt, the pc ligand is severely distorted from planarity and can adopt domed, saddled, waved and mixed non-planar conformations; the crystal symmetry is the most important factor for the conformational heterogeneity.
