Chiral tridentate bis(oxazol-2-ylimino) isoindoline-based pincer ligands: isolation and characterization deligation from prepared Cd-ligand complexes.

The first isolation and structural characterization of a series of chiral trinitrogen 1,3-bis(4,5-dihydrooxazol-2-ylimino)isoindoline-based pincer ligands are reported. Cadmium complexes, isolated as Cd(L2X)2 where L2X is the deprotonated form of L2XH = 1,3-bis(4,5-dihydro-4-(R)-phenyloxazol-2-ylimino)-isoindoline ((R,R)-5H) or 1,3-bis(4,5-dihydro-4-(S)-iso-propyloxazol-2-ylimino)isoindoline ((S,S)-6H) were prepared in situ via traditional or microwave-based techniques with the latter being more efficient but less able to be scaled up at this time. Ligands (R,R)-5H and (S,S)-6H were isolated via deligation from their respective cadmium complexes using a thiol-based ligand exchange protocol.

Accessing Ambiphilic Phosphine Boronates through C-H Borylation by an Unforeseen Cationic Iridium Complex.

Ambiphilic molecules, which contain a Lewis base and Lewis acid, are of great interest based on their unique ability to activate small molecules. Phosphine boronates are one class of these substrates that have interesting catalytic activity. Direct access to these phosphine boronates is described through the iridium-catalyzed C-H borylation of phosphines.

Thiocyanate-Ligated Heterobimetallic {PtM} Lantern Complexes Including a Ferromagnetically Coupled 1D Coordination Polymer.

A series of heterobimetallic lantern complexes with the central unit {PtM(SAc)4(NCS)} have been prepared and thoroughly characterized. The {Na(15C5)}[PtM(SAc)4(NCS)] series, 1 (Co), 2 (Ni), 3 (Zn), are discrete compounds in the solid state, whereas the {Na(12C4)2)}[PtM(SAc)4(NCS)] series, 4 (Co), 5 (Ni), 6 (Zn), and 7 (Mn), are ion-separated species. Compound 7 is the first {PtMn} lantern of any bridging ligand (carboxylate, amide, etc.

Increases in intravenous magnesium use among hospitalized patients: an institution cross-sectional experience.

Background: Among hospitalized patients, indications for the measurement of magnesium levels and treatment of hypomagnesemia with intravenous magnesium are not well defined. Recently, there have been reports of worldwide shortages of intravenous magnesium sulphate.

Objective: To examine secular trends in the administration of intravenous magnesium on hospital wards at a tertiary care institution.

Synthesis of a phosphapyracene via metal-mediated cyclization: structural and reactivity effects of acenaphthene precursors.

Metal-mediated synthesis of a new heterocycle, 1-phenyl-phosphapyracene (Ph-4, Ph-PyraPhos), by tandem phosphination/cyclization of peri-substituted 5-bromo-6-chloromethylacenaphthene (3) was investigated for comparison to Pt-catalyzed formation of 1-phosphaacenaphthenes (2, AcePhos) from the analogous naphthalene precursor (1). Reaction of PH2Ph with , NaOSiMe3 and a Cu catalyst gave ; a Pt catalyst yielded PHPh(CH2Ar) (Ph-11, Ar = 5-Br-acenaphthyl). Deprotonation of a complex of this secondary phosphine, [Pt((R,R)-Me-DuPhos)(Ph)(PHPh(CH2Ar))][PF6] (17), generated the phosphido intermediate Pt((R,R)-Me-DuPhos)(Ph)(PPhCH2Ar) (Ph-8), which cyclized to give [Pt((R,R)-Me-DuPhos)(Ph)(Ph-PyraPhos)][PF6] (18).

Phosphine-directed C-H borylation reactions: facile and selective access to ambiphilic phosphine boronate esters.

Ambiphilic ligands have received considerable attention over the last two decades due to their unique reactivity as organocatalysts and ligands. The iridium-catalyzed C-H borylation of phosphines is described in which the phosphine is used as a directing group to provide selective formation of arylboronate esters with unique scaffolds of ambiphilic compounds. A variety of aryl and benzylic phosphines were subjected to the reaction conditions, selectively providing stable, isolable boronate esters upon protection of the phosphine as the borane complex.

Generic immunosuppression in solid organ transplantation: a Canadian perspective.

The introduction of generic immunosuppressant medications may present an opportunity for cost savings in solid organ transplantation if equivalent clinical outcomes to the branded counterparts can be achieved. An interprofessional working group of the Canadian Society of Transplantation was established to develop recommendations on the use of generic immunosuppression in solid organ transplant recipients (SOTR) based on a review of the available data. Under current Health Canada licensing requirements, a demonstration of bioequivalence with the branded formulation in healthy volunteers allows for bridging of clinical data.

Synthesis and characterization of an unsymmetrical cobalt(III) active site analogue of nitrile hydratase.

The design, synthesis, and characterization of an unsymmetrical diamidato-dithiol ligand (H(4) 1, where the hydrogen atoms represent deprotonatable amide and thiol protons) and its cobalt(III) complex, a synthetic analogue of the cobalt-containing nitrile hydratase enzyme family, are reported. The ligand was prepared in 24% yield from an overall eight-step synthetic pathway following a modified protocol established in our laboratory that includes two peptide couples using O-(1H-benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate as the coupling agent. The ligand and all precursors were characterized by NMR spectroscopy and elemental analysis.

Novel metal complexes containing a chiral trinitrogen isoindoline-based pincer ligand: in situ synthesis and structural characterization.

The first synthesis and characterization of metal coordinated complexes containing in situ prepared chiral trinitrogen 1,3-bis(4,5-dihydrooxazol-2-ylimino)isoindoline-based pincer ligands are reported. Two zinc complexes, isolated as Zn(L)(2), where L = 1,3-bis(4,5-dihydro-4-(R)-phenyloxazol-2-ylimino)isoindoline ((R,R)-5) or 1,3-bis(4,5-dihydro-4-(S)-iso-propyloxazol-2-ylimino)isoindoline ((S,S)-6), respectively, are reported. Complexes Zn((R,R)-5)(2) and Zn((S,S)-6)(2) were prepared in situ through the condensation of phthalonitrile with enantiopure 2-amino-4-(R)-phenyloxazoline ((R)-3) or 2-amino-4-(S)-iso-propyloxazoline ((S)-4) in the presence of ZnCl(2) at 80 °C in dry toluene over 3-4 days.

catena-Poly[[[bis-(N,N-dimethyl-formamide)iron(II)]-{μ-2,2'-bis-(diphenyl-phosphino-yl)-N,N'-[(1R,2R)-cyclo-hexane-1,2-di-yl]dibenzamide}] bis-(perchlorate) N,N-dimethyl-formamide disolvate].

The title extended solid coordination compound, {[Fe(C(44)H(40)N(2)O(4)P(2))(C(3)H(7)NO)(2)](ClO(4))(2)·2C(3)H(7)NO}(n), was crystallized un-ex-pectedly from the reaction mixture containing the Trost ligand (1R,2R)-(+)-1,2-diamino-cyclo-hexane-N,N'-bis-(2'-di-phenyl-phosphinobenzo-yl) and Fe(ClO(4))(2)·6H(2)O in a 1:1 ratio in dimethyl-formamide (DMF) under reflux conditions. The polymeric complex is characterized by Fe(II) metal centers that are coordinated by two oxidized Trost ligands, each coordinated in a bidentate fashion in a square plane, along with two DMF mol-ecules above and below the plane [average Fe-O(DMF) = 2.086 (4) Å], forming an overall pseudo-octa-hedral geometry.

Carbon-yl[tris-(3,5-diphenyl-pyrazol-1-yl-κN)methane]copper(I) hexa-fluorido-phosphate-dichloro-methane-diethyl ether (4/3/1).

In the title compound, [Cu(C(46)H(34)N(6))(CO)]PF(6)·0.75CH(2)Cl(2)·0.25C(4)H(10)O, the Cu(I) atom is coordinated by three N atoms from the tridentate chelating tris-(3,5-diphenyl-pyrazol-1-yl)methane ligand (average Cu-N distance = 2.

Reactions of site-differentiated [Fe4S4]2+, 1+ clusters with sulfonium cations: reactivity analogues of biotin synthase and other members of the S-adenosylmethionine enzyme family.

The first examples of reduced 3:1 site-differentiated Fe(4)S(4) clusters have been synthesized as [Fe(4)S(4)(LS(3))(SR')](3-) (R=Et, Ph) by chemical reduction of previously reported [Fe(4)S(4)(LS(3))(SR')](2-) clusters, and isolated as NBu(4)(+) salts. The reduced clusters were characterized by electrochemistry and EPR, 1H NMR, and Mössbauer spectroscopies. The reaction of oxidized clusters with the sulfonium ions [PhMeSCH(2)R](+) (R=COPh, p-C(6)H(4)CN) in acetonitrile results in electrophilic attack on coordinated thiolate and production of PhSMe and R'SCH(2)R when the reaction occurs at the unique cluster site.

The first complete identification of a diastereomeric catalyst-substrate (alkoxide) species in an enantioselective ketone hydrogenation. Mechanistic investigations.

The enantioselective hydrogenations of the dialkyl 3,3-dimethyloxaloacetate ketone substrates (2, 3, and 4; alkyl = Me, (i)Pr, and (t)Bu, respectively) were catalyzed by [Ru((R)-BINAP)(H)(MeCN)(n)(sol)(3-n)](BF(4)) (1, n = 0-3, sol = THF or MeOH, (R)-BINAP = (R)-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl) in up to 82% ee (R). Reaction of the active catalyst 1 with 1 equiv of substrate (2, 3, or 4) in THF or MeOH solution formed the diastereomeric catalyst-alkoxide complexes [Ru((R)-BINAP)(MeCN)(OCH(CO(2)R)-(C(CH(3))(2)CO(2)R))](BF(4)) (5/6 R = Me, 8/9 R = (i)Pr, and 10 R = (t)Bu, respectively) via hydride addition to the ketone carbonyl carbon and ruthenium addition to oxygen. The absolute configurations at the alkoxide groups ((R)- for the major diastereomers 5, 8, and 10) were determined via cleavage of the ruthenium-alkoxide bond with 1 equiv of HBF(4).