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The transition metal-promoted in situ nucleophilic addition of triethanolamine (teaH3) and N-methyldiethanolamine (mdeaH2) to the dicyanonitrosomethanide (dcnm) anion results in the formation of [Cu(hbnm)]·MeOH (1) and [Cu(mbnm)]·2MeCN (2), (hbnm = hydroxyethylaminobis(ethoxy(imino)methyl(cyano)nitrosomethanide) and mbnm = methylaminobis(ethoxy(imino)methyl(cyano)nitrosomethanide). Complexes 1 and 2 are coordination polymers, each containing the addition products of two alcohol arms of teaH3 and mdeaH2 to dcnm anions.

Suspending crystals of bis(pentafluorophenyl)mercury [Hg(C6F5)2] (1a) in a saturated n-hexane solution for a prolonged period results in transformation into the new polymorph [Hg(C6F5)2] (1 b) monoclinic P21/n, a = 11.7060(3) ��, b = 7.8531(2) ��, c = 13.5429(4) ��, �� = 107.247(3)��, V = 1189.00(6) ��3. The C-Hg-C angle in 1 b is 177.10(11)�� and the pentafluorophenyl rings are rotated 74.6(1)�� to each other in comparison to 1a, the form known for 50+ years, which has a rotation angle of 58.0(2)��. Polymorph 1 b could also be obtained by crystallization from chloroform, or a CHCl3/n-hexane (1:1) mixture at ���20 ��C, or by seeding with a crystal of 1 b. Theoretical calculations suggest that the barrier to rotation is low.

Examination of the crystal structures of (Me4N)(dcnm) (1), (Me4N)(dcnom) (2), and (Me4N)(nbdm) (3) [dcnm = dicyanonitrosomethanide, dcnom = dicyanonitromethanide, nbdm = nitroso-N,N-bis(dicyanometh...

Conventional bench top and solvothermal synthesis are determined to be reliable methods in the synthesis of coordination compounds containing the dicyanonitromethanide (dcnom) anion. From conventional bench top synthesis, [Ni(phen)3](dcnom)2 (1a), [Cu(phen)3](dcnom)2 (1b), [Cu(en)3](dcnom)2 (4), [Cu3(Hpz)3(H2O)(OH)(pz)3]Cl(dcnom)·H2O (7) and [Ag(Hpz)2(dcnom)] (8) (where phen = 1,10-phenanthroline, en = 1,2-ethylenediamine, Hpz = pyrazole and pz = pyrazolate) are obtained. With solvothermal synthesis, [Ni(phen)2(H2O)(dcnom)](dcnom) (2), [Cu(phen)2(dcnom)](dcnom) (3), [Cu(en)2(dcnom)2] (5) and [Cu(pn)2(dcnom)2] (6) (where pn = 1,3-propylenediamine) are formed. Both nitro κ1(O) and nitrile κ1(N) coordination modes are observed for the dcnom anion.

The transition metal-promoted in situ nucleophilic addition of methanol and ethanol to a nitrile arm of dicyanonitrosomethanide (dcnm) resulted in the formation of cyano[imino(methoxy)methyl]nitrosomethanide (cmnm) and cyano[imino(ethoxy)methyl]nitrosomethanide (cenm) respectively. In the presence of 4,4′-bipyridine (4,4′-bipy), [Ni(cmnm)2(4,4′-bipy)]·½DMF (1), [Ni(cenm)2(4,4′-bipy)]·EtOH (2) and [Zn(cmnm)2(4,4′-bipy)]·2H2O (3) were isolated as 1D chains. When copper ions were used, a dinuclear structure, namely [Cu2(cmnm)4(4,4′-bipy)] (4) was observed. Synthesis of 1, 2 and 4 also required the presence of CeCl3·6H2O. The cmnm ligands in complex 3 display unique coordination modes to the metal ions, namely κ2(N,O)Zn. Finally, the hydrogen bonding in 3 generates three interpenetrating 3D networks with unusual bsn (or β-Sn) net topology.

Three manganese clusters have been synthesised via the reaction of Mn II with cyano(imino(methoxy)methyl)nitrosomethanide (cmnm), obtained from the in situ nucleophilic addition of MeOH to dicyanonitrosomethanide (dcnm). X-ray crystallographic studies show that the complex [Mn II 3 (cmnm) 6 ]·MeOH ( 1 ) is a linear trinuclear species, with a central octahedral and two outer trigonal-prismatic manganese(II) ions. Two mixed-valent tetranuclear complexes [Mn II 2 Mn III 2 O 2 (cmnm) 4 Cl 2 (MeOH) 6 ] ( 2 ) and [Mn II 2 Mn III 2 O 2 (cmnm) 4 Cl 2 (MeOH) 4 (pzH) 2 ]·2MeOH ( 3 ) (pzH = pyrazole) contain two Mn II and two Mn III ions in butterfly-type structures, with the six-coordinate ‘body’ Mn III ions bridged to the seven-coordinate ‘wingtip’ Mn II ions by μ 3 -O 2− and by nitroso oxygen atoms of the cmnm ligands. The formation of the trinuclear and tetranuclear manganese clusters is dependent on the stoichiometry used in the reactions. Solid state DC magnetic susceptibility studies on complexes 1 and 3 reveal that antiferromagnetic interactions are dominant within the clusters. Fits of the data reveal an S = 5 / 2 ground state for 1 and a S = 0 ground state for 3 , with several close lying excited states found in both cases.

A series of heterobimetallic complexes [RE₂Ca(OQ)₈]·nHOQ(RE = Sm, Gd, Tb, Ho, Tm, Yb, Lu, Y, Sc) and the isostructural [Gd₂Mg(OQ)₈] were synthesised and structurally characterised. They were mainly obtained after direct reactions of the elemental rare earth metals with calcium metal in the presence of 8-hydroxyquinoline (HOQ) and a 1, 3, 5-tri-tert-butyl-benzene (tBuB) flux, and some complexes were synthesised by pseudo solid-state rearrangement reactions between powdered RE(OQ)₃ and AE(OQ)₂ (AE = Mg, Ca) in a 1, 2, 4, 5-tetramethylbenzene (TMB) flux, at elevated temperatures. The linear trinuclear [RE₂Ca(OQ)₈] moieties show a six-coordinate central calcium atom flanked by two eight-coordinate rare earth atoms surrounded by six chelating-bridging OQ and two terminal chelating OQ ligands. The structurally novel [Sc₂Ca(OQ)₈] has a bent Sc-Ca-Sc backbone and exhibits an eight-coordinate central calcium and two seven-coordinate scandium ions.

The reaction of a thiophene-containing ligand, (Z)-3-hydroxy-3-phenyl-1-(thiophen-2-yl)prop-2-en-1-one (Hhtp), with hydrated lanthanoid chloride salts has resulted in the isolation of two tetranuclear clusters, [Ln4(μ3-OH)2{(μ-O)-κ2-htp}2{(μ-O)2-κ2-htp}2(κ2-htp)6] [Ln = Nd (1), Eu (2)] and an erbium pentanuclear cluster, [Er5(μ3-OH)4(μ4-OH){(μ-O)-κ2-htp}4(κ2-htp)6] (3). The clusters have been characterised by elemental analysis, mass spectrometry, infrared spectroscopy and X-ray single-crystal structural determination. The luminescent properties of cluster 2 have been assessed, and, at 25 °C, quenching of luminescent emission was found to predominantly occur. However, incremental addition of selected coordinating solvents was found to promote luminescence at 25 °C, showing a linear relationship at low analyte concentrations

The heterobimetallic 1D-polymeric alkali metal/lanthanoid [AMLn(Q)4]n [Q = OQ (8-quinolinolate): AM = Li, Ln = Tb, Ho, Er; AM = K, Ln = Er; Q = MQ (2-methyl-8-quinolinolate): AM = Rb; Ln = Tb, Er] complexes were obtained after rearrangement reactions between AM(Q) and Ln(Q)3 in a 1,2,4,5-tetramethylbenzene flux at elevated temperatures. In these compounds, the eight-coordinate lanthanoid ion is surrounded by four (O, N) chelating Q ligands, which bridge to the adjacent alkali metal through their oxygen atoms to form the linear polymers. Dimeric [Cs2(MQ)2(HMQ)2] was obtained from an attempt to prepare [CsEr(MQ)4]n, and the caesium atoms are each ligated by one terminal HMQ and one chelating-bridging MQ ligand. In addition, the chelating-bridging ligands in [Cs2(MQ)2(HMQ)2] and in the rubidium derivatives [RbLn(MQ)4]n (Ln = Tb, Er) exhibit bonding of the π-electron system to coordination saturate the large ionic alkali metal ion. The reaction of Yb(MQ)3 in the presence of K2C2O4·H2O afforded the monomeric heterobimetallic [KYb2(MQ)7] complex in which the three metal atoms are arranged in a triangular fashion. They are surrounded by seven MQ ligands, which display the previously encountered chelating (O, N) and the chelating-bridging μ-κ2(N,O):κ1(O) and μ3-κ2(N,O):κ1(O):κ1(O) ligation modes. Heating K(OQ) in 1,2,3,4-tetrachlorobenzene gave crystals of 8-hydroxyquinolinium chloride. The structure of [Na4(OQ)4(H2O)8]n, obtained by neutralisation, has sodium ions coordinated by one chelating OQ and four aqua ligands, the latter bridge to adjacent sodium ions to give a double stranded 2D-polymer.

Trivalent rare earth complexes of the unsymmetrical 3-(2'-thienyl)-5-(trifluoromethyl)pyrazolate (ttfpz) ligand, namely [RE(ttfpz)(3)(thf)(3)]center dot nsolv, where thf = tetrahydrofuran [RE = La, solv = PhMe, n = 0.5 (1); RE = Sm, n = 0 (2); RE = Tb, solv = thf, n = 1 (3)], [RE(ttfpz)(3)(thf)(2)] [RE = Y (4), Ho (5), Lu (6), Sc (7)] and [RE(ttfpz)(3)(dme)(2)]center dot nsolv, where dme = 1,2-dimethoxyethane [RE = La, n = 0 (8a); RE = La, solv = Et2O, n = 0.5 (8b); RE = Eu, solv = dme, n = 1 (9)], were prepared, mainly by redox transmetallation/protolysis from the free metal, Hg(C6F5)(2) and ttfpzH, and structurally characterised. In the nine-coordinate, pseudo-octahedral complexes 1 and 2, eta(2)-pyrazolate and thf ligands are in a facial arrangement, whereas they are arranged meridionally in 3. In the eight-coordinate complexes 4-7 the arrangement of the eta(2)-pyrazolate and thf ligands can be described as in between pseudo-trigonal bipyramidal and -square pyramidal. Ten-coordinate complexes 8a, 8b and 9 exhibit eta(2)-bonded pyrazolates and two chelating dme ligands as opposed to the nine-coordinate 3,5-diphenylpyrazolate (Ph(2)pz) complexes [RE(Ph(2)pz)(3)(dme)(2)], which possess one unidentate and one chelating dme ligand, suggesting that the ttfpz ligand is less bulky than Ph(2)pz.

Rearrangement reactions between Ln(MQ)3 and AE(MQ)2 (MQ = 8-quinaldinolate) at 200–300 °C in a 1,2,4,5-tetramethylbenzene (TMB) flux afforded the homoleptic heterobimetallic complexes [Ln2AE(MQ)8] (Ln = Eu, Gd, Tb, Er with AE = Mg; Ln = La, Eu with AE = Ca) and [Eu3Ba(MQ)11]·2TMB. From an attempt to prepare [La2Mg(MQ)8], [Mg4(MQ)8] was isolated, and it was also obtained with the heterobimetallics from syntheses in which Ln = Eu, Gd, Tb. Surprisingly, [Er3(MQ)7CO3] was isolated from an attempted synthesis of [Er2Ca(MQ)8], and the Eu analogue was prepared from Eu(MQ)3 and CaCO3 in TMB at 210 °C. The [Ln2AE(MQ)8] complexes have a trinuclear structure with a linear or nearly linear Ln–AE–Ln array. Octacoordinate Ln atoms have one terminal chelating (N, O) MQ ligand and three chelating-bridging MQ ligands that link to AE through the phenolic oxygen atoms, leading to hexacoordination of AE. In [Eu3Ba(MQ)11]·2TMB, an Eu atom is positioned above the Ba–Eu vector of a somewhat bent Eu–Ba–Eu unit. All atoms are octacoordinate, and the structure features μ3-η2(N,O):η1(O):η1(O) MQ ligands in addition to terminal chelating and chelating-bridging μ-η2(N,O):η1(O) MQ groups observed in [Ln2AE(MQ)8] complexes. The three modes of ligation are also observed in [Mg4(MQ)8] where Mg is hexacoordinate but with two different arrays. [Ln3(MQ)7CO3] complexes have a perpendicular Ln–Ln–Ln arrangement with two octacoordinate metal atoms flanking a heptacoordinate one. Carbonate binding features the new η1(O)-μ3-η1(O'):η1(O'):η1(O')-η1(O") ligation mode. The carbonate ligand chelates to each of the outer Ln atoms, which are also linked to one chelating and two chelating-bridging MQ ligands. Attached to the central Ln atom is a carbonate oxygen atom, four oxygen atoms from chelating-bridging MQ ligands and a terminal MQ chelate.

The reaction of europium 8-quinolinolate Eu(OQ) 3 with calcium 8-quinolinolate, Ca(OQ) 2 , in the flux 1,2,4,5-tetramethylbenzene (TMB) at 210 °C yields the bimetallic [Eu 2 Ca(OQ) 8 ], which is a linear tri-nuclear complex with two eight coordinate europium atoms flanking a six coordinate calcium atom bonded by six bridging phenolate oxygen atoms. A similar reaction between La(OQ) 3 and Co(OQ) 2 gave [LaCo 2 (OQ) 7 ], in which two six coordinate cobalt atoms flank an eight coordinate lanthanum atom with six bridging phenolate oxygen atoms and a terminal OQ group.

A variety of transition metal complexes involving picolylcyanoacetamides (pica = NCCH2CONH-R; R = 2-picolyl- (2pica), 3-picolyl- (3pica), 4-picolyl- (4pica)) and thiocyanate have been synthesised and their solid-state structures have been determined. The complexes were all obtained from reactions between the corresponding metals salts and pica ligands with sodium thiocyanate under ambient conditions. Both 3pica and 4pica coordinate to the metal solely through the nitrogen atom of the picolyl group and form discrete tetrahedral [M(NCS)2(pica)2] (3pica; M = Mn, Zn; 4pica; M = Co) and octahedral [M(NCS)2(3pica)4] (M = Co, Fe, Ni) complexes. In addition, one-dimensional N,S-thiocyanate-bridged coordination polymers poly-[M(µ-NCS)2(pica)2] (3pica; M = Cd; 4pica; M = Co, Cd) were obtained. The ligand 2pica gave the discrete octahedral complexes [Co(NCS)2(2pica)2] and [Cd(NO3)2(2pica)2] in which 2pica chelates in a bidentate fashion through its picolyl and carbonyl groups. Magnetic susceptibility measurements on the cobalt(ii) complexes were performed and showed short-range antiferromagnetic coupling for the [Co(NCS)2(4pica)2]n 1D polymer.

The divalent complexes [M(ttfpz)(2)(thf)(4)] (ttfpz = 3-(2'-thienyl)-5-(trifluoromethyl)pyrazolate; M = Yb, 1, Ca, 2, Sr, 3, Ba, 4; thf = tetrahydrofuran) and [M(ttfpz)(2)(dme)(n)] (M = Ca, 5, Sr, 6, Yb, 7, n = 2; M = Ba, 8, n = 3; dme = 1,2-dimethoxyethane) have been prepared by redox transmetallation/protolysis reactions employing the free metals, Hg(C(6)F(5))(2) and ttfpzH in donor solvents and their structures determined. The monomeric structures exhibit η(2)-bound pyrazolate ligands with eight-coordinate metal atoms for complexes 1-7 and a ten-coordinate metal for 8. The pyrazolate ligands in the thf-complexes 1-4 as well as dme-derivatives 5 and 6 are in a transoid configuration, whilst in complex 7 the ttfpz ligands exhibit a cisoid relationship. In 8 the ligands have an intermediate role in between cisoid and transoid.

From the pyrazoles 3,5-di-(2′-furanyl)pyrazole (fu2pzH), 3-phenyl-5-(2′-thienyl)pyrazole (PhtpzH) and 3-(2′-furanyl)-5-(2′′-naphthyl)pyrazole (funappzH), a range of alkaline earth and lanthanoid pyrazolate complexes has been prepared by redox transmetallation/protolysis reactions between free metals, Hg(C6F5)2 and the pyrazoles, by reaction of I2‐activated metals with the pyrazoles, and in one case by a similar reaction of unactivated metal, in the donor solvents tetrahydrofuran (thf) and 1,2-dimethoxyethane (dme). Thus the divalent [Ca(Phtpz)2(thf)4], [Ba(Phtpz)2(thf)4] and [Ca(funappz)2(thf)4]·(thf) complexes, the heteroleptic [Yb(Phtpz)I(thf)4] and the trivalent [La(fu2pz)3(thf)3]·2thf complex have been prepared and structurally characterized, as well as the dme complexes [Yb(Phtpz)2(dme)2] and [Eu(Phtpz)3(dme)2]. Highlights include the first trans-[LnII(pz)I(thf)4] complex, a rare transoid [Ln(pz)2(dme)2] complex and a complex with both chelating and unidentate dme. In all cases, the Phtpz complexes exhibit pronounced positional disorder of the 2-thienyl and phenyl groups in the solid state, as do the two polymorphs of the parent pyrazole.

Two novel trinuclear CuII complexes have been synthesised from the nucleophilic addition derivatives of the small cyano anion, dicyanonitrosomethanide (dcnm). The reaction of CuII with the water adduct ligand, carbamoylcyanonitrosomethanide (ccnm) and teaH3 (triethanolamine) in a basic MeOH/MeCN solution results in the formation of [Cu3(acnm)2(teaH2)2]·2MeOH (1) (acnm = amidocarbonyl(cyano)nitrosomethanide and teaH2– = singly deprotonated triethanolamine). The reaction of CuII with dicyanonitrosomethanide (dcnm) and m-xylenediamine in a basic MeOH/MeCN solution results in the formation of [Cu3(cimm)2(a3acnm)2]·6MeCN (2) (cimm = cyano(imido(methoxy)methyl)nitrosomethanide and a3acnm = {amino(3-aminomethylphenyl)methylimino}methyl(cyanonitrosomethanide)). Both complexes display linear trinuclear CuII metallic cores. Solid state DC magnetic susceptibility studies were performed on 1 and 2. Compound 1 revealed very strong antiferromagnetic interactions between central and terminal Cu atoms, while compound 2 displayed ferromagnetic interactions because of the orthogonal relationship of the terminal and the central ‘magnetic’ orbitals, which contrasts with these orbitals being coplanar in 1 thus providing strong superexchange pathways involving Cu-N-O-Cu moieties.

A new class of homoleptic organoamido rare earth complexes [Ln(L(Me) or L(Et))(3)] (Ln = La, Ce, Nd; L(Me/Et) = p-HC(6)F(4)N(CH(2))(2)NMe(2)/Et(2)) exhibiting (Ar)CF-Ln interactions has been isolated from redox-transmetallation/protolysis (RTP) reactions between the free metals, Hg(C(6)F(5))(2) and L(Me/Et)H in tetrahydrofuran, together with low yields of [Ln(L(Me))(2)F](3) (Ln = La, Ce) or [Nd(L(Et))(2)F](2) species, resulting from C-F activation reactions. The structures of the homoleptic complexes have eight-coordinate Ln metals with two tridentate (N,N',F) amide ligands including (Ar)CF-Ln bonds and either a bidentate (N,F) ligand (Ln = La, Ce, Nd; L(Et)) or a bidentate (N,N') ligand (Ln = Nd; L(Me)), in an unusual case of linkage variation. All (Ar)CF-Ln bond lengths are shorter than or similar to the corresponding Ln-NMe(2)/Et(2) bond lengths. In [Ln(L(Me))(2)F](3) (Ln = La, Ce) complexes, there is a six-membered ring framework with alternating F and Ln atoms and the metal atoms are eight-coordinate with two tridentate (N,N',F) L(Me) ligands, whilst [Nd(L(Et))(2)F](2) is a fluoride-bridged dimer.