TY - JOUR
T1 - Solid-state coordination chemistry of the oxomolybdate-organodiphosphonate/ nickel-organoimine system
T2 - Structural influences of the secondary metal coordination cation and diphosphonate tether lengths
AU - Burkholder, Eric
AU - Golub, Vladimir
AU - O'Connor, Charles J.
AU - Zubieta, Jon
PY - 2004/11/1
Y1 - 2004/11/1
N2 - The hydrothermal reactions of a molybdate source, a nickel(II) salt, tetra-2-pyridylpyrazine (tpyprz), and organodiphosphonic acids H 2O3P(CH2)nPO3H 2 (n = 1-5) of varying tether lengths yielded a series of organic-inorganic hybrid materials of the nickel-molybdophosphonate family. A persistent characteristic of the structural chemistry is the presence of the {Mo5O15(O3PR)2}4- cluster as a molecular building block, as noted for the one-dimensional materials [{Ni2(tpyprz)2}Mo5O15{O 3P(CH2)4PO3}]·6.65H 2O (6·6.65H2O) and [{Ni2(tpyprz) 2}Mo5O15-{O3P(CH2) 5PO3}]·3.75H2O (8·3.75H 2O), the two-dimensional phases [{Ni4(tpyprz) 3}{Mo5O15(O3PCH2CH 2PO3)}2]· 23H2O (3·23H2O) and [{Ni3(tpyprz)2(H 2O)2}(Mo5O15)(Mo2O 4F2){O3P(CH2)3PO 3}2]·8H2O (5· 8H2O), and the three-dimensional structures [{Ni2(tpyprz)(H 2O)3]Mo5O15{O3P(CH 2)3PO3)}]·H2O (4·H2O) and [{Ni2(tpyprz)(H2O) 2}Mo5O15 {O3P(CH2) 4PO3}]·2.25H2O (7·2.25H2O). In the case of methylenediphosphonic acid, the inability of this ligand to tether adjacent pentanuclear clusters precludes the formation of the common molybdophosphonate building block, manifesting in contrast a second structural motif, the trinuclear {(Mo3O8)x(O 3PCH2PO3)y} subunit of [{Ni(tpyprz)-(H2O)2}(Mo3O8) 2 (O3PCH2PO3)2] (1) which had been previously observed in the corresponding methylenediphosphonate phases of the copper-molybdophosphonate family. Methylenediphosphonic acid also provides a second phase, [Ni2(tpyprz)2][MO 7O21(O3PCH2PO3)] ·3.5H2O (9·5H2O), which contains a new heptamolybdate cluster {Mo7O21(O3PCH 2PO3)}4- and a cationic linear chain {Ni(tpyprz)}n4n+substructure. The structural chemistry of the nickel-molybdophosphonate series contrasts with that of the corresponding copper-molybdophosphonate materials, reflecting in general the different coordination preferences of Ni(II) and Cu(II). Consequently, while the Cu(II)-organic complex building block of the copper family is invariably the binuclear {Cu2(tpyprz)}4+ subunit, the Ni(II) chemistry with tpyprz exhibits a distinct tendency toward catenation to provide {Ni 3(tpyprz)2]6+, {Ni4(tpyprz) 3}8+, and {Ni(tpyprz)}n4n+ building blocks as well as the common {Ni2(tpyprz)}4+ moiety. This results in a distinct structural chemistry for the nickel(II)-molybdophosphonate series with the exception of the methylenediphosphonate derivative 1 which is isostructural with the corresponding copper compound [{Cu2(tpyprz) (H2O)2}(Mo3O8)2(O 3PCH2PO3)] (2). The structural chemistry of the nickel(II) series also reflects variability in the number of attachment sites at the molybdophosphonate clusters, in the extent of aqua ligation to the Ni(II) tpyprz subunit, and in the participation of phosphate oxygen atoms as well as molybdate oxo groups in linking to the nickel sites.
AB - The hydrothermal reactions of a molybdate source, a nickel(II) salt, tetra-2-pyridylpyrazine (tpyprz), and organodiphosphonic acids H 2O3P(CH2)nPO3H 2 (n = 1-5) of varying tether lengths yielded a series of organic-inorganic hybrid materials of the nickel-molybdophosphonate family. A persistent characteristic of the structural chemistry is the presence of the {Mo5O15(O3PR)2}4- cluster as a molecular building block, as noted for the one-dimensional materials [{Ni2(tpyprz)2}Mo5O15{O 3P(CH2)4PO3}]·6.65H 2O (6·6.65H2O) and [{Ni2(tpyprz) 2}Mo5O15-{O3P(CH2) 5PO3}]·3.75H2O (8·3.75H 2O), the two-dimensional phases [{Ni4(tpyprz) 3}{Mo5O15(O3PCH2CH 2PO3)}2]· 23H2O (3·23H2O) and [{Ni3(tpyprz)2(H 2O)2}(Mo5O15)(Mo2O 4F2){O3P(CH2)3PO 3}2]·8H2O (5· 8H2O), and the three-dimensional structures [{Ni2(tpyprz)(H 2O)3]Mo5O15{O3P(CH 2)3PO3)}]·H2O (4·H2O) and [{Ni2(tpyprz)(H2O) 2}Mo5O15 {O3P(CH2) 4PO3}]·2.25H2O (7·2.25H2O). In the case of methylenediphosphonic acid, the inability of this ligand to tether adjacent pentanuclear clusters precludes the formation of the common molybdophosphonate building block, manifesting in contrast a second structural motif, the trinuclear {(Mo3O8)x(O 3PCH2PO3)y} subunit of [{Ni(tpyprz)-(H2O)2}(Mo3O8) 2 (O3PCH2PO3)2] (1) which had been previously observed in the corresponding methylenediphosphonate phases of the copper-molybdophosphonate family. Methylenediphosphonic acid also provides a second phase, [Ni2(tpyprz)2][MO 7O21(O3PCH2PO3)] ·3.5H2O (9·5H2O), which contains a new heptamolybdate cluster {Mo7O21(O3PCH 2PO3)}4- and a cationic linear chain {Ni(tpyprz)}n4n+substructure. The structural chemistry of the nickel-molybdophosphonate series contrasts with that of the corresponding copper-molybdophosphonate materials, reflecting in general the different coordination preferences of Ni(II) and Cu(II). Consequently, while the Cu(II)-organic complex building block of the copper family is invariably the binuclear {Cu2(tpyprz)}4+ subunit, the Ni(II) chemistry with tpyprz exhibits a distinct tendency toward catenation to provide {Ni 3(tpyprz)2]6+, {Ni4(tpyprz) 3}8+, and {Ni(tpyprz)}n4n+ building blocks as well as the common {Ni2(tpyprz)}4+ moiety. This results in a distinct structural chemistry for the nickel(II)-molybdophosphonate series with the exception of the methylenediphosphonate derivative 1 which is isostructural with the corresponding copper compound [{Cu2(tpyprz) (H2O)2}(Mo3O8)2(O 3PCH2PO3)] (2). The structural chemistry of the nickel(II) series also reflects variability in the number of attachment sites at the molybdophosphonate clusters, in the extent of aqua ligation to the Ni(II) tpyprz subunit, and in the participation of phosphate oxygen atoms as well as molybdate oxo groups in linking to the nickel sites.
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U2 - 10.1021/ic049201k
DO - 10.1021/ic049201k
M3 - Article
C2 - 15500339
AN - SCOPUS:7244239318
SN - 0020-1669
VL - 43
SP - 7014
EP - 7029
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 22
ER -