Syntheses and exploration of the catalytic activities of organotin(IV) compounds.

Six organotin(IV) compounds (1-6) have been synthesized by reaction of the polydentate pro-ligands H3L and H2L, respectively, with the corresponding diorganotin chlorides. All of the compounds were characterized by FT-IR spectroscopy, H, C{H}, and Sn (H) NMR spectroscopy, HRMS spectrometry, and single-crystal X-ray diffraction. The solid-state structures show that all of the compounds are monomeric (except compound 3) and contain a penta-coordinated tin atom.

Mononuclear organogermanium(IV) catalysts for a [3 + 2] cycloaddition reaction.

Three mononuclear Ge(IV) compounds, [(CH)Ge(CHNO)] (1), [(CH)Ge(CHNO)] (2), and [(CH)Ge(CHNO)] (3), have been synthesized by the reaction of pro-ligands H2L1 (CHNO), H2L2 (CHNO), and H2L3 (CHNO) with (CH)GeCl in the presence of triethylamine. All compounds were characterized by FT-IR spectroscopy and NMR spectroscopy. Single crystal X-ray diffraction analysis shows that the germanium(IV) atom exhibits a five-coordinated geometry in compounds 1 and 2.

Correction: NHC-Zn alkyl catalyzed cross-dehydrocoupling of amines and silanes.

Correction for 'NHC-Zn alkyl catalyzed cross-dehydrocoupling of amines and silanes' by Adimulam Harinath , , 2023, https://doi.org/10.1039/d3ob00453h.

NHC-Zn alkyl catalyzed cross-dehydrocoupling of amines and silanes.

An -heterocyclic carbene-zinc alkyl complex [ImZn(CHCH)] (Im = imidazol-2-ylidene and Dipp = 2,6-diisopropylphenyl) acts as a catalyst in the cross-dehydrogenative coupling (CDC) of a wide range of primary and secondary amines and hydrosilanes to yield a substantial quantity of the corresponding aminosilanes with good chemoselectivity at room temperature. A broad substrate scope was observed during the zinc-catalyzed CDC reaction. Two zinc complexes, [{ImZn(-NHPh)(NHPh)}] (Mes = mesityl) (3) and [{ImZn(CHCH)(-H)}] (4), were isolated and structurally characterized as intermediates through controlled reactions to ascertain the CDC mechanism.

Bis(catecholato)germane: an effective catalyst for Friedel-Crafts alkylation reaction.

Bis(catecholato)germane, [Ge(CHO)(HO)] (1), was synthesized by the reaction of catechol and germanium oxide in water according to a reported method. Complex 1 was characterized by FT-IR spectroscopy, NMR spectroscopy and elemental analysis. Complex 1 was employed as a Lewis acid catalyst in the Friedel-Crafts alkylation reaction of indole with various aldehydes and β-nitrostyrene derivatives separately.

Catalytic Hydroboration and Reductive Amination of Carbonyl Compounds by HBpin using a Zinc Promoter.

The chemoselective hydroboration of aldehydes and ketones, catalyzed by Zinc(II) complexes [κ -(PyCH=NR)ZnX ] [R=CPh , X=Cl (1) and R=Dipp (2,6-diisoropylphenyl) and X=I (2)], in the presence of pinacolborane (HBpin) at ambient temperature and under solvent-free conditions, which produced the corresponding boronate esters in high yield, is reported. Zinc metal complexes 1 and 2 were derived in 80-90% yield from the reaction of iminopyridine [PyCH=NR] with anhydrous zinc dichloride in dichloromethane at room temperature. The solid-state structures of both zinc complexes were confirmed using X-ray crystallography.

Unusual absence of FRET in triazole bridged coumarin-hydroxyquinoline, an active sensor for Hg2+ detection.

A triazole-bridged coumarin conjugated quinoline sensor has been 'click'-synthesized by Cu(i) catalyzed Huisgen cycloaddition, and it exhibited high selectivity for toxic Hg2+. Surprisingly, no evidence of energy transfer from the quinoline moiety to coumarin has been found, substantiated by time-resolved fluorescence study. The possible binding mode of this sensor to Hg2+ has been established via NMR study, steady-state and time-resolved fluorescence spectroscopy, which is further supported by TDDFT calculations.

Trinuclear Lanthanide Coordination Clusters: Single-Molecule-Magnet Behavior and Catalytic Activity in the Friedel-Crafts Alkylation Reaction.

A new multidentate ligand (H L) was synthesized by the condensation reaction of 4-tert-butyl-2,6-diformylphenol and 2-amino-4-nitrophenol. The reaction of the ligand with hydrated lanthanide nitrate produced two isostructural trinuclear coordination clusters: [DyLn L (DMF) (H O) ] ⋅ 3.8DMFLn=Dy (1) and Nd (2) (DMF=N, N-dimethylformamide).

Highly Active Dinuclear Titanium(IV) Complexes for the Catalytic Formation of a Carbon-Heteroatom Bond.

A series of mononuclear titanium(IV) complexes with the general composition κ-[R{NHPhP(X)}Ti(NMe)] [R = CH, X = Se (3b); R = trans-CH, X = S (4a), Se (4b)] and [{κ-N(PPhSe)}Ti(NMe)] (6b) and two dinuclear titanium(IV) complexes, [CH{(NPhPS)(N)}Ti(NMe)] (3c) and [{κ-N(PPhSe)}Ti(NMe)] (6c), are reported. Dinuclear titanium(IV) complex 6c acts as an efficient catalyst for the chemoselective addition of an E-H bond (E = N, O, S, P, C) to heterocumulenes under mild conditions. The catalytic addition of aliphatic and aromatic amines, alcohol, thiol, phosphine oxide, and acetylene to the carbodiimides afforded the corresponding hydroelemented products in high yield at mild conditions with a broader substrate scope.

Alkali metal complexes as efficient catalysts for hydroboration and cyanosilylation of carbonyl compounds.

We report here reactions between the N-adamantyliminopyrolyl ligand 2-(AdN[double bond, length as m-dash]CH)-C4H3NH (L-H) and alkali metal hexamethyldisilazides [MN(SiMe3)2] (M = Li, Na and K) to afford the dimeric [{2-(AdN[double bond, length as m-dash]CH)-C4H3NLi(THF)}2] (1), [{2-(AdN[double bond, length as m-dash]CH)-C4H3N}{Na(THF)1.5}2] (2) and polymeric [{2-(AdN[double bond, length as m-dash]CH)-C4H3NK(THF)}n] (3) complexes at ambient temperature. A one-pot reaction between L-H, [KN(SiMe3)2] and alkaline earth metal diiodide (AeI2) in a 2 : 2 : 1 molar ratio, which resulted in the formation of a heteroleptic Ae metal complex [κ2-{2-(AdN[double bond, length as m-dash]CH)-C4H3N}2Ae(THF)2] [Ae = Mg (4), Ca (5)], is also reported.

Ring Opening Polymerization and Copolymerization of Cyclic Esters Catalyzed by Group 2 Metal Complexes Supported by Functionalized P-N Ligands.

We report the preparation of alkali and alkaline earth (Ae) metal complexes supported by 2-picolylamino-diphenylphosphane chalcogenide [(PhP(=E)NHCH(CHN)] [E = S (1-H); Se (2-H)] ligands. The treatment of the protic ligand, 1-H or 2-H, with alkali metal hexamethyldisilazides at room temperature afforded the corresponding alkali metal salts [M(THF)(PhP(=E)NCH(CHN)] [M = Li, E = S (3a), Se (3b)] and [{M(THF) (PhP(=E)NCH(CHN)}] [M = Na, E = S (4a), Se (4b); M = K, E = Se (5b)] in good yield. The homoleptic Ae metal complexes [κ-(PhP(=Se)NCH(CHN)Mg(THF)] (6b) and [κ-{(PhP(=Se)NCH(CHN)}M(THF) ] (M = Ca (7b), Sr (8b), Ba (9b)] were synthesized by the one-pot reaction of 2-H with [KN(SiMe)] and MI in a 2:2:1 molar ratio at room temperature.

Highly Active and Iso-Selective Catalysts for the Ring-Opening Polymerization of Cyclic Esters using Group 2 Metal Initiators.

A series of alkali and alkaline earth (Ae) metal complexes bearing 1,2-phenylene(bis-diphenylphosphinothioic/selenoic amine) [{Ph P(E)NH} C H ] (E=S (1-H2); Se (2-H2) ligands are reported. Alkali metal complexes [{Ph P(S)N} C H ]Na(THF) (3 a) [{Ph P(Se)N} C H ]Na(THF) (3 b), and [{Ph P(Se)N} C H ]K(THF) (4 b) were obtained in good yield by treating protic ligands 1-H2 or 2-H2 with metal hexamethyldisilazides [MN(SiMe ) ] (M=Na or K) at ambient temperature. The Ae metal complexes formulated as [{Ph P(E)N} C H ]M(THF) [E=S, M=Ca (5 a), Sr (6 a), Ba (7 a); E=Se, M=Ca (5 b), Sr (6 b), Ba (7 b)] can be synthesized by using two routes.

Lead ion induced chemodosimeter approach of a tripodal hydroxyl-quinoline based phospho-ester through P-O bond cleavage.

Lead ion induced P-O bond breaking with instant colour change was observed in a tripodal hydroxyl-quinoline based phosphor-ester (). A new penta-coordinated lead chelate complex [Pb4HQ6(ClO4)2] was found. The hydrolysis reaction followed by P-O bond cleavage with 'Pb-O' and 'Pb-N' bond formation proved the chemodosimeter approach.

Imidazolin-2-iminato Ligand-Supported Titanium Complexes as Catalysts for the Synthesis of Urea Derivatives.

The reactions of tetrakis(dimethylamido)titanium(IV) [Ti(NMe2)4] with three different imidazolin-2-imines (Im(R)NH; R = tert-butyl (tBu), mesityl (Mes), and 2,6-diisopropylphenyl (Dipp)) afforded the corresponding titanium imidazolin-2-iminato complexes [(Im(R)N)Ti(NMe2)3] (R = tBu, 1a; R = Mes, 1b; R = Dipp, 1c). Treatment of complex 1a with two different carbodiimides [R'N═C═NR'; R' = cyclohexyl (Cy) and isopropyl (iPr)] resulted in the formation of imidazolin-2-iminato titanium mono(guanidinate) complex of the type [(Im(R)N)Ti(R'NC(NMe2)NR') (NMe2)2 (R' = iPr; R = tBu (2a), R = Dipp (2c); R' = Cy, R = tBu (3a)], as yellow solid in 94% yield. However, a similar reaction of 1b and 1c with 2 equiv of phenyl isocyanates at ambient temperature resulted in the formation of corresponding titanium bis(ureate) complexes [(Im(R)N)Ti{κ(2)-OC(NMe2)NPh}2(NMe2)] (R = Mes, 4b and R = Dipp, 4c).

Targeted water soluble copper-tetrazolate complexes: interactions with biomolecules and catecholase like activities.

Two new mononuclear water soluble copper(II) complexes, [Cu{(5-pyrazinyl)tetrazolate}2(1,10-phenanthroline)] 1 and [Cu{(5-pyrazinyl)tetrazolate}(1,10-phenanthroline)2](NO3)0.5(N3)0.5 2, have been synthesized using the metal mediated [2 + 3] cycloaddition reaction between copper bound azide and pyrazinecarbonitrile.

Imidazol-2-ylidene-N'-phenylureate ligands in alkali and alkaline earth metal coordination spheres--heterocubane core to polymeric structural motif formation.

The synthesis and isolation of two potassium, one lithium and two calcium complexes of imidazol-2-ylidene-N'-phenylureate ligands [Im(R)NCON(H)Ph] [(R = tBu (1a); Mes (1b) and Dipp (1c); Mes = mesityl, Dipp = 2,6-diisopropylphenyl] are described. Potassium complexes, [{κ(2)-(Im(Mes)NCONPh)K}4] (2b) and [{κ(3)-(Im(Dipp)NCONPh)K}2{KN(SiMe3)2}2]n (2c), were prepared in good yields by the reactions of 1b and 1c, respectively, with potassium bis(trimethyl)silyl amide at ambient temperature in toluene. Lithium complex [{(2,6-tBu2-4-Me-C6H2O)Li(Im(tBu)NCON(H)Ph)}2{Im(tBu)NCON(H)Ph}] (3a) was isolated by a one-pot reaction between 1a and LiCH2SiMe3, followed by the addition of 2,6-tBu2-4-Me-C6H2OH in toluene.

Microporous La-metal-organic framework (MOF) with large surface area.

A microporous La-metal-organic framework (MOF) has been synthesized by the reaction of La(NO3 )3 ⋅6 H2 O with a ligand 4,4',4''-s-triazine-1,3,5-triyltri-p-aminobenzoate (TATAB) featuring three carboxylate groups. Crystal structure analysis confirms the formation of 3D MOF with hexagonal micropores, a Brunauer-Emmett-Teller (BET) surface area of 1074 m(2)  g(-1) and high thermal and chemical stability. The CO2 adsorption capacities are 76.

Heavier alkaline earth metal complexes with phosphinoselenoic amides: evidence of direct M-Se contact (M = Ca, Sr, Ba).

We report here a series of heavier alkaline earth metal complexes with a phosphinoselenoic amide ligand using two synthetic routes. In the first route, the heavier alkaline earth metal bis(trimethylsilyl)amides [M{N(SiMe3)2}2(THF)n] (M = Ca, Sr, Ba) were treated with phosphinoselenoic amine [Ph2P(Se)NH(CHPh2)] (3), prepared by the treatment of bulky phosphinamines [Ph2PNH(CHPh2)] (1) with elemental selenium in THF, and afforded homoleptic alkaline earth metal complexes of composition [M(THF)2{Ph2P(Se)N(CHPh2)}2] (M = Ca (7), Sr (8), Ba (9)). The metal complexes 7–9 can also be obtained via salt metathesis route where the alkali metal phosphinoselenoic amides of composition [{(THF)2M′Ph2P(Se)N(CHPh2)}2] (M′ = Na (5) and K (6)) were reacted with respective metal diiodides in THF at ambient temperature.

Control of molecular architecture by steric factors: mononuclear vs polynuclear manganese(III) compounds with tetradentate N2O2 donor Schiff bases.

Three manganese(III) compounds, [Mn(III)(vanoph)(DMF)(H(2)O)]ClO(4) (1), [Mn(III)(vanoph)(N(3))(H(2)O)]·2H(2)O (2) and [Mn(III)(saloph)(μ(1,3)-N(3))](n) (3), where H(2)vanoph = N,N'-(1,2-phenylene)-bis(3-methoxysalicylideneimine), H(2)saloph = N,N'-(1,2-phenylene)-bis(salicylideneamine) are tetradentate N(2)O(2) ligands and DMF = N,N-dimethylformamide, have been prepared and characterised by elemental analysis, IR and UV-Vis spectroscopy and single-crystal X-ray diffraction studies. Compounds 1 and 2 are monomeric but compound 3 consists of a chain system with the repeating unit [Mn(III)(saloph)(N(3))] bridged by μ-1,3 azide. Compound 1 crystallises in monoclinic space group P2(1)/n with cell dimensions of a = 11.

Zinc-zinc bonded decamethyldizincocene Zn2(η(5)-C5Me5)2 as catalyst for the inter- and intramolecular hydroamination reaction.

The Zn-Zn bonded compound [(η(5)-Cp*)(2)Zn(2)] was investigated as catalyst for the inter- and intramolecular hydroamination reaction. High reaction rates under mild conditions were observed. This is the first application of a Zn-Zn bonded compound as catalyst.

Trigonal propeller-shaped [Mn(III)3M(II)Na] complexes (M = Mn, Ca): structural and functional models for the dioxygen evolving centre of PSII.

Two new polynuclear heterometallic cluster complexes with [Mn(III)(3)M(II)Na] (M = Mn, Ca) core were synthesized using two in situ formed Schiff bases. The compounds were structurally characterized by single crystal X-ray analysis. The compound with [Mn(III)Ca(II)Na] appeared to catalyse water oxidation which was followed by using Clark electrode and online mass spectrometry.

Presence or absence of a central Se atom in silver selenide/selenolate clusters with halite topology: syntheses and properties of [(Ph(3)PAg)(8)Ag(6)(mu(6)-Se)(1-x/2)(SePh)(12)](x+) (x = 0, 1).

Two types of Ph(3)P/Ph ligated Ag(14)Se(13-x) (x = 0, 0.5) clusters with halite topology were synthesized that differ by the occupation/nonoccupation of the central position by a 13th Se atom and the resulting charge: neutral [(Ph(3)PAg)(8)Ag(6)(mu(6)-Se)(SePh)(12)].11THF (1) and ionic [(Ph(3)PAg)(8)Ag(6)(mu(6)-Se)(0.

A cubic coordination framework constructed from benzobistriazolate ligands and zinc ions having selective gas sorption properties.

Two novel metal coordination polymers, [Zn5Cl4(BBTA)3].3 DMF (1), and [ZnCl(BBTA)(0.5)(DMA)] (2) {H2-BBTA = 1H,5H-benzo(1,2-d:4,5-d')bistriazole}, have been synthesized under solvothermal conditions using ZnCl2 and H2-BBTA in DMF (DMF = N,N'-dimethylformamide) or DMA (DMA = N,N'-dimethylacetamide).