The laboratory synthesis of the oxygen-evolving complex (OEC) photosystem II has been objective synthetic chemists since early 1970s. However, absence structural information on OEC hampered these efforts. Crystallographic reports that have appearing at ever-improving resolution over past ten years finally provided invaluable and show it comprises a [Mn 3 CaO 4 ] distorted cubane, to which is attached fourth, external Mn atom, whole unit polypeptides primarily by aspartate glutamate...

Spin doctoring: The already high spin of S=51/2 a Mn25 complex has been pushed even higher, by approximately 20 %, to S=61/2 targeted substitution the azide ligands with an N,O-chelating group. This significant adjustment, or tweaking, suggests general possibility that given type complicated, high-nuclearity, high-spin molecule can exhibit differing ground states appropriate modification peripheral ligation.

Quantum tunneling of magnetization (QTM) steps have been observed for a mixed 3d–4f single-molecule magnet the first time in hysteresis loops {Mn12Gd}. This phenomenon is assigned to larger than usual exchange coupling 4f atom with {Mn12} shell. improved quantum behavior important class SMMs opens up prospects its detailed study using methods. Gd purple, Mn(II) yellow, Mn(III) blue, O red, N green. Detailed facts importance specialist readers are published as "Supporting Information". Such...

The reaction between oxide-centered, triangular [MnIII3O(O2CR)6(py)3](ClO4) (R = Me (1), Et (2), Ph (3)) compounds and methyl 2-pyridyl ketone oxime (mpkoH) affords a new family of Mn/carboxylato/oximato complexes, [MnIII3O(O2CR)3(mpko)3](ClO4) [R (4), (5), (6)]. As in 1-3, the cations 4-6 contain an [MnIII3(mu3-O)]7+ core, but with each Mn2 edge now bridged by eta1:eta1:mu-RCO2- eta1:eta1:eta1:mu-mpko- group. tridentate binding mode latter causes buckling formerly planar resulting relative...

Taking the high road: The unification of azide and hmp− (hmpH=2-(hydroxymethyl)pyridine) ligands has provided a route to two salts new Mn10 cation with an aesthetically pleasing, high-symmetry structure. (see excerpt structure; MnII yellow, MnIII blue, O red, N green, C gray) is completely ferromagnetically coupled possesses S=22 ground state, one highest values ever reported.

A new [Dy3Bi8O6Cl3(saph)9] (1) Werner-type cluster has been prepared, which is the first DyIII/BiIII polynuclear compound with no metal-metal bond and one of very few LnIII-BiIII (Ln = lanthanide) heterometallic complexes reported to date. The molecular 1 deliberately transformed its 1-D analogue [Dy3Bi8O6(N3)3(saph)9]n (2) via replacement terminal Cl- ions by end-to-end bridging N3- groups. overall metallic skeleton (and 2) can be described as consisting a diamagnetic {Bi8} unit an...

The reaction of [Mn3O(O2CR)6(py)3](ClO4) (R = Me, Et) with methyl 2-pyridyl ketone oxime (mpkoH) in a 1:3 molar ratio MeOH/MeCN leads to [Mn3O(O2CR)3(mpko)3](ClO4) 80-90% isolated yield. Ferromagnetic exchange interactions between the three MnIII ions nonplanar [MnIII3O]7+ triangular core lead spin ground state S 6; single-crystal studies reveal temperature and sweep rate dependent hysteresis loops expected for single-molecule magnet.

Singles networks: The use of 1,3-propanediol and 2-methyl-1,3-propanediol in manganese carboxylate chemistry leads to two new 3D coordination polymers with an unprecedented Mn19 repeating unit. have open framework structures nanometer-sized cavities (see picture; Na not visible, Mn blue, O red, C gray). units a ground spin state S=23/2 behave as single-molecule magnets.

Wheelin' and dealin': The M10 molecular wheels [M10(OMe)20(O2CR)10] (M=Ga, R=Me; M=Fe, R=Ph) were modified to M18 in a nontemplate synthesis upon incorporation of diolate ligand (see space-filling model [Ga18(pd)12(pdH)12(O2CMe)6(NO3)6]6+; Ga yellow, O red, N blue, C gray; pdH2=1,3-propanediol). Remarkably, dissolution MeOH converts both back into the wheels.

A [Mn(III)(11)Mn(II)(6)(mu(4)-O)(8)(mu(3)-L)(4)](25+) (L = N(3)(-) or OCN(-)) octahedral unit is reported, occurring within 1D (1)(infinity) and 2D (2)(infinity) coordination polymers, as well the corresponding 0D discrete cluster 3. It possesses a giant ground-state spin value, determined in case of 3 to be S 37, second largest reported date. In addition, compound displays single-molecule magnet (SMM) behavior, thus largest-spin SMM.

Double impact: The use of both azide and di-2-pyridylketone-derived ligands has provided new Mn24 (left) Mn26 complexes (right) with loop dumbbell structures that are made up two covalently linked Mn12 Mn13 units, respectively. Both single-molecule magnets, the complex displays largest barrier for magnetization reversal in a MnII/III known to date. MnII yellow, MnIII blue, O red, N green, C gray.

Abstract The coordination chemistry of di‐2‐pyridyl ketone and related ligands is reviewed. An outline the variety such presented. References are given to methods for synthesis that not available on market. activation carbonyl group(s) some towards further reactions seems be an emergent area synthetic inorganic chemistry. each ligand with metals briefly described. Emphasis placed structural features physical properties (mainly magnetic) resulting metal clusters polymers. diversity complexes...

Unusual {NiII3LnIII(μ-OR)6}3+ complexes with a "star" topology have been prepared ligands derived from the metal-promoted reduction of di-2-pyridyl ketone under solvothermal conditions; DyIII member shows weak single-molecule-magnet behavior.

The initial employment of 2-pyridinealdoxime in 3d/4f chemistry has led to a Ni(II)(8)Dy(III)(8) cluster with an unprecedented metal topology; the compound unusual structure, is highest-nuclearity oxime date, and exhibits slow magnetization relaxation.

The initial employment of 2-(hydroxymethyl)pyridine in 4f metal chemistry has afforded a new family Ln(III)(9) clusters with sandglass-like topology and dual physical properties; the Dy(III) member shows single-molecule magnetism behavior, while Eu(III) analogue exhibits intense red photoluminescence.

The first {Mn31} cluster (1) has been prepared from carboxylate ions and the chelating/bridging ligand α-methyl-2-pyridine-methanol. Compound 1 possesses a unique nanosized structural topology with one of largest energy barriers reported to-date for high-nuclearity 3d-metal clusters. Single-crystal magnetic hysteresis studies reveal presence loops below 5 K, highest temperatures which molecular observed 3d-based SMMs.

Abstract The use of phenyl 2‐pyridyl ketone [(ph)(2‐py)CO] and its oxime [(ph)(2‐py)CNOH] in manganese benzoate chemistry has been investigated. reaction an excess (ph)(2‐py)CNOH with Mn(O 2 CPh) ·2H O affords the mononuclear complex [Mn II (O {(ph)(2‐py)CNOH} ]·1.2H ( 1· 1.2H O) high yield. Mn ion is coordinated by two monodentate benzoates N , ′‐bidentate chelating molecules a cis ‐ trans fashion. comproportionation between n Bu 4 MnO (3:1) presence MeCN/EtOH/CH Cl leads to isolation...

The use has been explored of both azide (N3-) and alkoxide-containing groups such as the anions 2-(hydroxymethyl)pyridine (hmpH), 2,6-pyridinedimethanol (pdmH2), 1,1,1-tris(hydroxymethyl)ethane (thmeH3) triethanolamine (teaH3) in Mn cluster chemistry. 1:1:1:1 reactions hmpH, NaN3 NEt3 with Mn(ClO4)(2).6H 2O or Mn(NO3)2.H2O MeCN/MeOH afford [MnII4MnIII6O4(N3)4(hmp)12](X)2 [X=ClO4- (1), N3- (2)]. [Mn10(mu4-O) 4(mu3-N3)4]14+ core cation a tetra-face-capped octahedral topology, central MnIII6...

Syntheses, crystal structures, and magnetochemical characterization are reported for the three new nickel(II) clusters [Ni14(OH)4(N3)8(pao)14(paoH)2(H2O)2](ClO4)2 (1), [Ni12Na2(OH)4(N3)8(pao)12(H2O)10](OH)2 (2), [Ni5(ppko)5(H2O)7](NO3)5 (3) (paoH = pyridine-2-carbaldehyde oxime, ppkoH di-2-pyridyl ketone oxime). The reaction of Ni(ClO4)2·6H2O with paoH NBun4N3 in H2O/MeCN presence NEt3, gave 1 65% yield. Complex 2 was obtained 60% yield from NiCl2·6H2O NaN3 NaOH. Ni(NO3)2·6H2O EtOH LiOH...

The syntheses, crystal structures, magnetochemical characterization, and theoretical calculations are reported for three new iron clusters [Fe 6O 2(NO3) 4(hmp) 8(H 2O) 2](NO3)2 (1), [Fe4(N3)6(hmp)6] (2), [Fe8O3(OMe)(pdm)4(pdmH) 4(MeOH)2](ClO4)5 (3) (hmpH=2-(hydroxymethyl)pyridine; pdmH2=2,6-pyridinedimethanol). reaction of hmpH with iron(III) sources such as Fe(NO3) 3.9H2O in the presence NEt 3 gave 1, whereas 2 was obtained from a similar by adding an excess NaN3. Complex good yield pdmH...

The combined use of the anion phenyl(2-pyridyl)ketone oxime (ppko(-)) and azides (N(3)(-)) in nickel(II) carboxylate chemistry has afforded two new Ni(II)(5) clusters, [Ni(5)(O(2)CR')(2)(N(3))(4)(ppko)(4)(MeOH)(4)] [R' = H (1), Me (2)]. structurally unprecedented {Ni(5)(μ-N(3))(2)(μ(3)-N(3))(2)}(6+) cores clusters are almost identical contain five Ni(II) atoms a bowtie topology. Two N(3)(-) ions end-on doubly bridging other triply bridging. μ(3)-N(3)(-) groups link central with peripheral...

Employment of the monoanion 2,6-diacetylpyridine dioxime (dapdoH2) as a tridentate chelate in palladium(II) and platinum(II) chemistry is reported. The syntheses, crystal structures, spectroscopic physicochemical characterization, biological evaluation are described [PdCl(dapdoH)] (1) [PtCl(dapdoH)] (2). Reaction PdCl2 with 2 equivs dapdoH2 MeOH under reflux gave 1, whereas same reaction PtCl2 place comparable yields (70–80%). divalent metal center both compounds coordinated by terminal...