TY - JOUR
T1 - The Hydrogen Oxide Bridging Ligand (H302-). 2. Effect of the Hydrogen Ion Concentration
AU - Bino, Avi
AU - Gibson, Dan
PY - 1984/4
Y1 - 1984/4
N2 - The trinuclear M(IV) cluster ion [M302(pr)6(H20)3]2+(M = Mo, W; pr = 02CC2H5) undergoes extensive hydrolysis in aqueous solution and produces hydroxo species. Dimerization and polymerization of these clusters proceed via formation of the hydrogen oxide bridging ligand, µ-H302-. This ligand is formed by a strong hydrogen bond between the hydroxo ligand of one cluster and an aquo ligand of another. In solution, all species exist in equilibrium and their relative concentration is pH dependent. Different crystalline products have been obtained by varying the hydrogen ion concentration of solutions containing the trinuclear cluster ion [M3O2(pr)6(H20)3]2+, M = Mo, W (in 0.5 M KNCS). When the H+ concentration is 1 M, crystals of [W302(pr)6(H20)3](NCS)2(1) are deposited. At [H+] = 0.05 M crystals of f[W302(pr)6(H20)2]2-(H302)}(NCS)3-H20 (2) and of its molybdenum analogue {[Mo302(pr)6(H20)2]2(H30)}(NCS)3.H20 (3) are obtained. When no acid is added, crystals of [W302(pr)6(H20)(H302)]NCS (4) are obtained. Crystals of the four compounds were subjected to a detailed X-ray structural analysis. Compound 1 forms monoclinic crystals, space group P21/c, with a = 17.953 (3)Å,b= 18.923 (3) Å, c = 10.034 (2) Å, β = 94.59 (2)½, V = 3398 (1) Å3, and Z = 4. Compound 2 forms triclinic crystals, space group Pi, with a = 11.334 (2) Å, b = 17.393 (3) Å, c = 9.011 (2) Å, α = 98.63 (3)½, β = 110.48 (3)½, 7 = 100.09 (2)½, V = 1595 (I) Å3, and Z = 1. Compound 3 is isostructural with 2 with a = 11.347 (2) Å, b = 17.399 (3) Å, c = 9.004 (2) Å, α = 98.69 (3)½, β = 110.57 (3)½, γ = 100.15 (3)½, and V= 1594 (1) Å3. Compound 4 forms monoclinic crystals, space group P21/c, with a = 14.842 (2) Å, b = 13.611 (2) Å, c = 16.432 (2) Å, β = 111.29 (2)½, V = 3093 (1) Å3, and Z = 4. Compound 1 contains discrete [W302(pr)6(H20)3]2+units (monocluster). The 2+ charge of the cation is balanced by two NCS-anions. In 2 and 3 two trinuclear clusters are bridged by a µ-H302-ligand and the 3+ charge of the dicluster is balanced by three NCS” ions. Structure 4 consists of infinite chains of triangular W3clusters (polycluster); each µ-H302-ligand bridges two adjacent clusters. The 0-0 separations in the H302” unit in compounds 2, 3, and 4 are 2.46 (1), 2.52 (1), and 2.44 (1) Å, respectively.
AB - The trinuclear M(IV) cluster ion [M302(pr)6(H20)3]2+(M = Mo, W; pr = 02CC2H5) undergoes extensive hydrolysis in aqueous solution and produces hydroxo species. Dimerization and polymerization of these clusters proceed via formation of the hydrogen oxide bridging ligand, µ-H302-. This ligand is formed by a strong hydrogen bond between the hydroxo ligand of one cluster and an aquo ligand of another. In solution, all species exist in equilibrium and their relative concentration is pH dependent. Different crystalline products have been obtained by varying the hydrogen ion concentration of solutions containing the trinuclear cluster ion [M3O2(pr)6(H20)3]2+, M = Mo, W (in 0.5 M KNCS). When the H+ concentration is 1 M, crystals of [W302(pr)6(H20)3](NCS)2(1) are deposited. At [H+] = 0.05 M crystals of f[W302(pr)6(H20)2]2-(H302)}(NCS)3-H20 (2) and of its molybdenum analogue {[Mo302(pr)6(H20)2]2(H30)}(NCS)3.H20 (3) are obtained. When no acid is added, crystals of [W302(pr)6(H20)(H302)]NCS (4) are obtained. Crystals of the four compounds were subjected to a detailed X-ray structural analysis. Compound 1 forms monoclinic crystals, space group P21/c, with a = 17.953 (3)Å,b= 18.923 (3) Å, c = 10.034 (2) Å, β = 94.59 (2)½, V = 3398 (1) Å3, and Z = 4. Compound 2 forms triclinic crystals, space group Pi, with a = 11.334 (2) Å, b = 17.393 (3) Å, c = 9.011 (2) Å, α = 98.63 (3)½, β = 110.48 (3)½, 7 = 100.09 (2)½, V = 1595 (I) Å3, and Z = 1. Compound 3 is isostructural with 2 with a = 11.347 (2) Å, b = 17.399 (3) Å, c = 9.004 (2) Å, α = 98.69 (3)½, β = 110.57 (3)½, γ = 100.15 (3)½, and V= 1594 (1) Å3. Compound 4 forms monoclinic crystals, space group P21/c, with a = 14.842 (2) Å, b = 13.611 (2) Å, c = 16.432 (2) Å, β = 111.29 (2)½, V = 3093 (1) Å3, and Z = 4. Compound 1 contains discrete [W302(pr)6(H20)3]2+units (monocluster). The 2+ charge of the cation is balanced by two NCS-anions. In 2 and 3 two trinuclear clusters are bridged by a µ-H302-ligand and the 3+ charge of the dicluster is balanced by three NCS” ions. Structure 4 consists of infinite chains of triangular W3clusters (polycluster); each µ-H302-ligand bridges two adjacent clusters. The 0-0 separations in the H302” unit in compounds 2, 3, and 4 are 2.46 (1), 2.52 (1), and 2.44 (1) Å, respectively.
UR - http://www.scopus.com/inward/record.url?scp=0001414351&partnerID=8YFLogxK
U2 - 10.1021/ic00169a023
DO - 10.1021/ic00169a023
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AN - SCOPUS:0001414351
SN - 0020-1669
VL - 23
SP - 109
EP - 115
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 1
ER -