The structure of Co(acac)2 reported by us [Burgess et al. (2000). Acta Cryst. C56, 649–650] has been reassessed in view of a recent article [Vreshch et al. (2010). Inorg. Chem. 49, 8430–8434], which suggests that the compound might actually be Cu(acac)2. Using the structure-factor data deposited with the original article, the evidence is slightly in favour of Cu(acac)2, although the crystallographic data alone, in this case, cannot unequivocally distinguish between the two possibilities. We concede that we may indeed have been mistaken, but that there is still some element of mystery.

As both professional work and education c ome to be more and more mediated by networked computers and electronic content managements system s (CMSs), it becomes possible to represent within professional education the systems of genres that c haracterize computer-mediated professional work, an d to dynamically simulate the systems of activity that t he genre systems mediate. However, students must pe rceive the genres and systems of genres as operating in two sy stems of activity, schooling and work. This paper r eports case study research on one such virtual learning en vironment (VLE) to explore how it both affords and constrains complex genre recognition and learning i n relation to time and space, conceived in terms of Bakhtin's concept of chronotope.

Reaction of [RhCl2Cp*](2) (Cp* = eta-C5Me5) with salicyloxazolines in the presence of NaOMe gives complexes [RhCl(R-saloxaz)Cp*] (1-4) which have been fully characterised. The diastereoselectivity of complexation depends on the substituents and the absolute configuration at the metal centre is unstable in solution. Treatment of 2 with 4-methylpyridine and NaSbF6 in methanol at reflux gave [Rh(4-Mepy) {(S)-Pr-i-saloxaz} Cp*][SbF6](5) whilst [Rh(OH2)(Me-2-saloxaz)Cp*][SbF6](6) was prepared by reaction of 1 with AgSbF6. Three complexes. [RhCl(Me-2-saloxaz)Cp*] (1), [RhCl{(S)-Pr-i-saloxaz}Cp*] (2), and [Rh(OH2)(Me-2-saloxaz)Cp*][SbF6] (6) have been characterised bv X-ray crystallography. Some of the complexes, after treatment with AgSbF6, have been tested as enantioselective catalysts for the Diels-Alder reaction of methacrolein with cyclopentadiene. (c) 2005 Elsevier B.V. All rights reserved.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Condensation of mono N-substituted chiral ethylenediamines and pyridine-2-methoxyimidate gives new chiral pyridine imidazolines (la-c). These react with [RuCl2(mes)](2) (mes = 1,3,5-trimethyl benzene) in the presence of NaSbF6 to give complexes [RuCI(L)-(mes)][SbF6] (5a-c) which after treatment with AgSbF6 are enantioselective catalysts for the Diels-Alder reaction of methacrolein and cyclopentadiene. The imidazoline catalysts are less selective than the corresponding oxazoline ones. Compounds la, 5b and 5c have been characterised by X-ray crystallography. (c) 2006 Elsevier B.V. All rights reserved.

Reaction of the dimers [RuCl2(eta6-arene)]2 (arene = benzene, p-cymene, mesitylene) with salicyloxazolines in the presence of NaOMe gives complexes [RuCl(R-saloxaz)(arene)] (1-5) which have been fully characterised. Complexes [RuL(iPr-saloxaz)(mes)]Y (L = py, 2-Mepy, 4-Mepy; PPh3; Y- = SbF6 or BPh4) 6-9 were prepared by treating the chloride 2a with ligand L and NaY (Y- = SbF6 or BPh4) in methanol at reflux. Halide complexes [RuX(iPr-saloxaz)(mes)](X = Br, 10; X = I, 11) were synthesised by treating 2a with AgSbF6 then with 1.2 equivalents of KBr or NaI, the methyl complex [RuMe(iPr-saloxaz)(mes)] 12 was synthesised from 2a by reaction with MeLi. Five complexes, [RuCl(iPr-saloxaz)(mes)] 2a, [RuCl(tBu-saloxaz)(p-cymene)] 3b, [RuCl(Ph-saloxaz)(mes)] 5a, [Ru(4-Mepy)(iPr-saloxaz)(mes)][SbF6] 7, and [Ru(PPh3)(iPr-saloxaz)(mes)][SbF6] 9, have been characterised by X-ray crystallography. Treatment of complexes 1-5 with AgSbF6 gives cationic species which are enantioselective catalysts for the Diels-Alder reaction of acroleins with cyclopentadiene, the effect of substituents on enantioselectivity has been examined.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

The X-ray crystal structures of cyclopalladated complexes are reported. Reaction of {[Pd(dmba)(μ-Cl)]2}, (1), (dmba=N(CH3)2CH2C6H5) with triphenylphosphine gave crystals containing {chloro–(triphenylphosphino)-bis[N,N-dimethylaminobenzyl-C1,N]palladium(II)} (2a) and {trans-bis(triphenylphosphino)-chloro-[N,N-dimethylaminozyl-C]palladium(II)} (2b). Complex (1) crystallises in the space group P2(1)/c with a=7.849(1)Å, b=15.635(3)Å, c=8.352(1)Å, β=109.29°, and Dcalc=1.895gcm−3 for Z=2. Complexes (2a) and (2b) crystallize together in the space group P2(1)/n with a=9.964(2) Å, b=34.228(5) Å, c=18.127(3) Å, β=91.91 °, and Dcalc=1.439gcm−3.

The synthesis, spectral properties and crystal structures of Cs2[W(bpy)(CN)6]·2H2O and (AsPh4)2[W(bpy)(CN)6]·3.5H2O are described. The anions of both salts show distorted antiprismatic geometry with very similar bond lengths and angles. The structure of the [W(bpy)(CN)6]2− anion is independent of the type of cation, in contrast to the octacyanotungstate(IV).

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

The structures of Pr(bipy)3(NCS)3, Pr(bipy)2(NO3)3, Pr(bipy)2Cl3(OH2)·EtOH and Pr(bipy)(S2CNEt2)3 are reported. Pr(bipy)3(NCS)3 has a monomeric structure with three N-bonded thiocyanates and three bidentate bipyridyl ligands, giving nine-coordinate praseodymium. Praseodymium is eight-coordinate in Pr(bipy)2Cl3(OH2)·EtOH and in Pr(bipy)(S2CNEt2)3 whilst Pr(bipy)2(NO3)3 is isostructural with the La, Nd and Lu analogues, having three bidentate nitrates and two bipyridyl ligands, affording 10-coordinate praseodymium. Factors affecting bond lengths in the compounds are discussed.

N,N-Dimethylbenzylamine, alkyl and aryl imines derived from benzaldehyde, and 2-phenyl-4,4-dimethyloxazoline all undergo cyclometallation with [IrCl2Cp*](2) (Cp*=eta-C5Me5) when treated with NaOAc in dichloromethane at room temperature. The imines are also cyclometallated by [RhCl2Cp*](2) under the same conditions whilst only N-alkyl imines are cyclometallated by [RuCl2(p-cymene)](2). The role of acetate in the cyclometallation is more than just as a base. X-Ray structures of cyclometallated complexes [MCl{C6H4-2-C(H)=NCH2CH2OMe-kappaC, N}(eta-ring)](M=Ir, Rh ring=Cp*; M=Ru, ring=p-cymene), [MCl{C6H4-2-C(H)=NCH2CH2OMe-kappaC, N}Cp*](M=Ir, Rh), [RuCl(eta(2)-O2CMe)(p-cymene)] and [IrCl2(NH2Ph)Cp*] are reported.

Reaction of LiL 3c (LH = 4(S)-isopropyl-2-oxazolinylbenzene) with Me3SnCl affords LSnMe3 3d. Attempts to transfer the oxazolinylphenyl to [RuCl2(mes)](2) or [RhCl2Cp*](2) using 3d failed, in both cases there is evidence for transfer of methyl with the formation of LSnMe2Cl 5. Reaction of 3d with [PdCl2(PhCN)(2)] leads to selective transfer of the aryloxazoline, forming [LPdCl](2) 6 which has been prepared independently via metathesis of [LPd(OAc)](2) 7 with lithium chloride. However, the reaction of 3d with [PdCl2(COD)] is not selective, transfer of both methyl and aryl occurring. The structures of 3d, 5 and 7 have been determined by X-ray diffraction.

Reaction of the dimers [MCl2Cp*]2 (M=Rh, Ir) with bis-oxazolines [NN=bis(2-oxazoline) (box), 2,2-bis(2-oxazolinyl)propane (bop), 1,2-bis(2-oxazolinyl)benzene (benbox)] in the presence of NaSbF6 (or KPF6) gives complexes [MCl(NN)Cp*][EF6] (E=P or Sb) which have been fully characterised. Treatment of some of these with AgSbF6 generates dications [Rh(OH2)(NN)Cp*]2+, some of which are fluxional at room temperature. One of these is an enantioselective catalyst for the Diels–Alder reaction of methacrolein and cyclopentadiene. Three complexes, [RhCl(iPr-box)Cp*][SbF6], [RhCl(iPr-bop)Cp*][SbF6] and [RhCl(Et-benbox)Cp*][SbF6] have been characterised by X-ray crystallography.

Only two of the four possible facial approaches of cyclohexa-1,3-diene to the double bond in 2-methyl-5,6-benzo-2-azabicyclo[2.2.2]oct-7-en-3-one 7 are observed, giving exo,endo- and endo,endo-Diels–Alder cycloadducts 10a and 11a at atmospheric pressure (exo- and endo-defined here by reference to the benzo- and etheno-bridges, respectively). Hydride reduction of the carbonyl in 10a provides an indirect route to 9, which is formally derived from 2-methyl-5,6-benzo-2-azabicyclo[2.2.2]oct-7-ene 6 but which is inaccessible directly owing to thermal retro-cycloaddition of 6. X-Ray crystal structures confirm the stereochemical assignments. Cycloaddition of cyclopentadiene to 7 follows a similar path and the results are compared with corresponding studies on 7-azabicyclo[2.2.1]heptene analogues where only exo-facial attack is observed. Through-space interactions with proximate etheno- and ethano-bridges give rise to substantial upfield 15N NMR shifts of amino and lactam nitrogen.

Treatment of the molybdenum tetracarbonyl complexes of [Mo(CO)4L2] (L2=pyridyl amine Schiff base ligands) with allyl chloride in refluxing THF afforded η3-allyl complexes [MoCl(CO)2L2(η3-allyl)] (1–9). These complexes have been characterised by various techniques including 1H-NMR, IR and FABMS spectroscopies and the single crystal X-ray structure determinations of the complexes [MoCl(CO)2{N(C6H4-2-OMe)C(Me)C5H4N}(η3-C3H5)] (3) and [MoCl(CO)2{N(Me)C(Ph)C5H4N}(η3-C3H5)] (4).

The complexes M(OTf)3(Ph3PO)4 where M=lanthanide metals and scandium have been prepared and characterised in the solid state by single crystal X-ray diffraction, infrared spectroscopy and elemental analysis. All the complexes have the ionic structure [M(OTf)2(Ph3PO)4]+[OTf]−. Single crystal X-ray structures for M=Sc, Nd and Lu are reported. In the complexes of the early lanthanides (LaNd) the metals are seven-coordinate with one monodentate, one bidentate triflate. The smaller lanthanide ions, and scandium, have six-coordinate structures with an approximate octahedral coordination about the metal where both triflates are bound as monodentate ligands. The solution structures have been analysed by electrospray mass spectrometry, which indicates that extensive ligand redistribution occurs. The complexes catalyse the Friedel Crafts acylation, alkenylation and alkylation of activated aromatics with modest increases in selectivity compared to the same reactions using scandium triflate.

A series of chiral bipyridine-type ligands 5-12 has been:synthesized: via: a de novo construction of the pyridine nucleus. The chiral moieties of the ligands originate from the monoterpene realm, namely, pinocarvone (13 --> 6, 7, and 9), myrtenal (18 --> 5), nopinone (21 --> 8 and 10), and menthone (28 --> 11 and 12); the first three precursors can be obtained in one step from beta- and alpha -pinene, respectively. Complexes of these ligands with molybdenum(0) (38-40) and copper(II) (41) have been characterized by single-crystal X-ray crystallography. While complex 38 exhibits polymorphism (monoclinic and tetragonal forms crystallize from the same batch), 41 is characterized by a tetrahedrally distorted geometry of the metal coordination. The Mo and Pd complexes exhibit modest asymmetric induction:in allylic substitution (43 --> 44), and the Cu(I) counterpart of 41, derived from 10 (PINDY) and Cu(OTf)(2), shows promising enantioselectivity (49-75% ee) and reaction rate (greater than or equal to 30 min at room temperature) in allylic oxidation of cyclic olefins (47 --> 48). The Cu(I) complex of 11 (MINDY) proved effective in cyclopropanation (49 --> 50) with up to 72% ee.

Reaction of the dimers [RuCl2(arene)]2 (arene = benzene, p-cymene, mesitylene) with bis(oxazolines) (N-N = bis(2-oxazoline) (box), 2,2-bis(2-oxazolinyl)propane (bop), 1,2-bis(2-oxazolinyl)benzene (benbox)) in the presence of NaSbF6 gives the complexes [RuCl(N-N)(arene)][SbF6] (1−8), which have been fully characterized. Treatment of these cations with AgSbF6 generates dications which in some cases are enantioselective catalysts for Diels−Alder reaction of methacrolein and cyclopentadiene. Two complexes, [RuCl(iPr-benbox)(p-cymene)][SbF6] (5) and [Ru(OH2)(iPr-bop)(mes)][SbF6]2 (10; mes = mesitylene), have been characterized by X-ray crystallography.