Triazolyl-phosphole and triazolyl-azaphosphole: synthesis, transition metal complexes and catalytic studies.

Phosphole and azaphosphole derivatives with triazole functionalities, [CH{1,2,3-NCCHC(PPh)}] (L1) and [CH{1,2,3-NC(Ph)C(PPh)}] (L2) were synthesized by reacting [(CH)(1,2,3-NC = CH--Br-CH)] and [(-Br-CH)(1,2,3-NC = CHCH)] with BuLi followed by the addition of dichlorophenylphosphine. The reactions of L1 and L2 with an excess of 30% HO afforded phosphole oxides [CH{1,2,3-NCCHC(P(O)Ph)}] (L1O) and [CH{1,2,3-NC(Ph)C(P(O)Ph)}] (L2O) as white crystalline solids. Stoichiometric reactions of L1 and L2 with [Ru(η--cymene)Cl] in CHCl yielded [RuCl(η--cymene)(L1-κ-)] (1) and [RuCl(η--cymene)(L2-κ-)] (2), respectively.

Solution combustion synthesis of ZnO doped CuO nanocomposite for photocatalytic and sensor applications.

ZnO-doped CuO nanocomposites (CuO-ZnO NPs) of 1, 3, and 5 mol% were prepared by the solution combustion method using ODH as a fuel (Oxlyl-hydrazide) at 500 °C and calcining at 1000 °C for two hours and the Structural, photocatalytic, and electrochemical properties were investigated by experimental and theoretical methods. X-ray diffraction (XRD) patterns revealed a crystallite size (D) range of 25 to 31 nm for pure CuO and 1, 3, and 5 mol% CuO-ZnO NPs. According to calculations, the optical energy band gap (Eg) of the NPs is between 2.

Ni, Pd and Pt pincer complexes of 2-(diphenylphosphanyl)--(2-(diphenyl-phosphanyl)benzyl)benzamide: synthesis, reactivity and catalytic studies.

In this article, the synthesis of bis(phosphine), -PhPCHC(O)N(H)CHCHPPh- (1) (hereafter referred to as "PNHP" and its anionic form as "PNP") and its group 10 metal chemistry and catalytic studies are described. PNHP (1) on reaction with NiCl(DME) and PdCl(COD) afforded pincer complexes, [MCl{(PNP)κ-,,}] (M = Ni, 2; Pd, 3). A similar reaction of 1 with PtCl(COD) yielded a chelate complex, [PtCl{(PNHP)κ-,}] (4), which on further treatment with LiHMDS produced the 1,2-azaphospholene-phosphine complex, [PtCl(Ph){(-P(Ph)CHCONCHCHPPh-)κ-,}] (5) P-C/P-N bond metathesis.

Luminescence Behavior of Cationic and Neutral Cu Complexes of Phosphine and Pyridine Embedded 1,2,3-Triazole.

Synthesis of a potentially polydentate, phosphine and pyridine embedded 1,2,3-triazole, -PhP(CH)C(CH)-1,2,3-N(CH)(Py) () (here onward referred to as "PNN") and its copper complexes are described. Reactions of with CuX yielded mononuclear [Cu{(PNN)-κ-}]X ( - ; X = I, CuBr and CuCl) and dinuclear [Cu{(PNN)-κ-}]X ( X = OTf, X = BF) complexes. Interestingly, the cationic complex [Cu{(PNN)-κ-}]I () in acetonitrile changes into neutral complex [Cu(μ-I)(μ-I)(NCCH){(PNN)-κ(μ-)(μ-)}](), which on addition of dichloromethane reverts back to the cationic form.

Synthesis, structural studies and Hirshfeld surface analysis of 2-[(4-phenyl-1-1,2,3-triazol-1-yl)methyl]pyridin-1-ium hexa-kis-(nitrato-κ ,')thorate(IV).

Reaction of thorium(IV) nitrate with 2-[(4-phenyl-1-1,2,3-triazol-1-yl)meth-yl]pyridine () yielded (H)[Th(NO)] or (CHN)[Th(NO)] (), instead of the expected mixed-ligand complex [Th(NO) ], which was detected in the mass spectrum of . In the structure, the [Th(NO)] anions display an icosa-hedral coordination geometry and are connected by H cations through C-H⋯O hydrogen bonds. The H cations inter-act N-H⋯N hydrogen bonds.

ZnCl-catalysed transfer hydrogenation of carbonyls and chemoselective reduction of the CC bond in α,β-unsaturated ketones.

This manuscript describes chemoselective reduction of CC in α,β-unsaturated ketones and the transfer hydrogenation of aldehydes and ketones catalysed by ZnCl-phosphinamino-triazolyl-pyridine (0.5 mol%) using KOH/PrOH as a H source. A detailed mechanistic study using DFT calculations (B3LYP-D3/def2-TZVP) revealed the key role of metal-ligand cooperation (MLC) in the catalytic reaction demonstrating the non-innocent behaviour of the phosphine ligand.

Arene displacement, C-H activation and acetonitrile insertion reactions enabled by coordination of a functionalized iminophosphorane to a Ru--cymene scaffold.

Reaction of a sterically demanding iminophosphorano-phosphine, PhPCHPhPNAr* (here onwards referred to as PCPNAr*; Ar* = 2,6-dibenzhydryl-4-methylphenyl), (1) with [Ru(η--cymene)Cl] yielded three different types of complex, [RuCl{(η--cymene)(PCPNAr*)-κ-}] (2), [RuCl{(P(O)CPNAr*)(κ-,)(-η-arene)}] (3) and [RuCl{(POCPNAr*)(κ-,)(-η-arene)}] (4), depending on the reaction conditions CH activation, tethered η-arene coordination, -metallation or PN bond cleavage/rearrangement reactions. Interestingly, a similar reaction in CHCN in the presence of AgBF resulted in the insertion of CHCN into the PN bond to form a novel metallacycle [Ru(NCMe){(PCPN(CH)CNAr*)-κ-,,}][BF] (5) containing 4- and 5-membered rings an aza-Wittig type reaction. Complex 4 showed very good catalytic activity in the transfer hydrogenation of carbonyl compounds.

Cu-Amidobis(phosphine)-Catalyzed Direct Amidation of Unactivated Alkanes via C(sp)-H Activation.

Herein, we describe an acid-base-free, sustainable, and efficient method for direct amidation of unactivated alkanes and toluene derivatives, using the dimeric Cu complex [Cu{-PhPCHCONCHPPh-}] (here onward referred to as [PNP-Cu]). Using this method, C(sp)-N bond formation was achieved through the activation of very challenging C(sp)-H bonds in cycloalkanes, alkenes, allyl groups, and benzyl groups, with tolerance toward ketonic groups, heterocycles, and halide functionalities. One of the precatalysts, (PNHP-Cu-Npht) was isolated and structurally characterized.

Cu-amidobis(phosphine) catalyzed C(sp)-C(sp) direct homo- and hetero-coupling of unactivated alkanes C(sp)-H activation.

Herein, we present a Cu-dimer, [Cu{PhPCHC(O)NCHPPh-}], which catalyzed direct C(sp)-H homocoupling of benzyl and cycloalkane derivatives with excellent yields and regio-selectivity. The method is very simple and tolerates various functionalities. Synergistic metal-ligand cooperativity was observed in Cu-N bond cleavage and protonation of nitrogen, and facilitates a bifunctional pathway, minimising the free energy corrugation for catalytic intermediates.

Structural Diversity and Rare η Cu-C Interactions in Cu Complexes of 1,2,3-Triazole-Functionalized Bisphosphines.

This manuscript describes the synthesis of copper complexes of 1,2,3-triazolyl-phosphines: -PhP(CH){1,2,3-NCCH)C(PPh)} (), (CH){1,2,3-NC(CH(-PPh))-C(PPh)} (), 3-PhP(CHN){1,2,3-NC(CH)C(PPh)} (), -PhP(CH){1,2,3-NC(CHN)C(PPh)} (), and {(3,5-PhPCH-)1,2,3-NCCH} (). The reactions of - with Cu salts afforded dimeric complexes having the general formula [Cu(μ -X)L] (L = , X = Cl, Br and I: - ; L= , X = Cl, Br and I: - ; L = ; X = Cl, Br, and I: -). The reaction of with CuI in a 1:2 molar ratio afforded 1D-coordination polymer [{(CuI){-PhP(CH){1,2,3-NC(CHN)C(PPh)}((-)(-))}}] ().

Catalytic utility of PNN-based Mn pincer complexes in the synthesis of quinolines and transfer hydrogenation of carbonyl derivatives.

This manuscript describes the synthesis of a triazolyl-pyridine-based phosphine, -((diphenylphosphaneyl)methyl)--methyl-6-(1-phenyl-1-1,2,3-triazol-4-yl)pyridin-2-amine, [2,6-{(PPh)CHN(Me)(CHN)(CHNCH)}] (1) (here onwards referred to as PNN) and its cationic and neutral Mn complexes and catalytic applications. The reaction of 1 with Mn(CO)Br afforded a cationic complex [Mn(CO)(PNN)]Br (2), which is highly stable in solid state, but in solution it gradually loses one of the CO groups to form a neutral complex [Mn(CO)(PNN)Br] (3). Complex 2 on treatment with AgBF also yielded a cationic complex [Mn(CO)(PNN)]BF (4).

Copper(I) Complexes of Amide Functionalized Bisphosphine: Proximity Enhanced Metal-Ligand Cooperativity and Its Catalytic Advantage in C()-H Bond Activation of Unactivated Cycloalkanes in Dehydrogenative Carboxylation Reactions.

The reactions of amide functionalized bisphosphine, -PhPCHC-(O)N(H)CHPPh- () (BalaHariPhos), with copper salts is described. Treatment of with CuX in a 1:1 molar ratio yielded chelate complexes of the type [CuX{(-PhPCHC(O)N(H)CHPPh-)}-κ] (X = Cl, ; Br, ; and I, ), which on subsequent treatment with KOBu resulted in a dimeric complex [Cu(-PhPCHC(O)(N)CHPPh-)] (). Interestingly, complexes - showed weak N-H···Cu interactions.

Cationic and Neutral Pd and Pt Pincer Complexes of Phosphinamino-Triazolyl-Pyridine [PN(H)N]: Pincer Ligand-Stabilized Palladium Nanoparticles and Their Catalytic Annulation of Internal Alkynes to Indenones.

We describe the synthesis of a triazolyl-pyridine-based aminophosphine, -(diphenylphosphaneyl)-6-(1-phenyl)-1-(1,2,3-triazol-4-yl)pyridine-2-amine [2,6-{(PPh)-N(H)(CHN)(CHNCH)}] [, PN(H)N hereafter], and its palladium and platinum complexes and their catalytic application. The reaction of with [M(COD)Cl] (M = Pd or Pt) afforded the cationic complex [(MCl){PN(H)N}-κ-P,N,N]Cl [M = Pd () or Pt ()]. Alternatively, compounds and were also synthesized by treating [2,6-{HN(CHN)(CHNCH)}] () with [M(COD)Cl] (M = Pd or Pt), followed by the addition of stoichiometric amounts of PPhCl and EtN.

Synthesis and characterization of the cyclodiphosphazane embedded macrocycle tetrabromo-resorcin[4]arene-tetrakis(cyclodiphosphazane) and its tetra-rhodium(I) complex.

The synthesis of a cyclodiphosphazane embedded macrocycle, tetrabromo-resorcin[4]arene-tetrakis(cyclodiphosphazane) [(μ-N(Bu)P){μ-(CHBr(-O)--CHBu)}] (1), and its tetra-rhodium(I) complex [(μ-N(Bu)P){μ-(CHBr(-O)--CHBu)}Rh(COD)Cl] (2) is described. The resorcin[4]arene backbone adopts a symmetric conformation in 1, which transforms into a symmetric conformation upon complexation with Rh(I) in the tetra-rhodium(I) complex 2, as evidenced by NMR spectroscopy and X-ray diffraction studies.

Synthesis and Photophysical Properties of Heavier Pnictogen Complexes.

Recent success in the synthesis of π-conjugated heavier pnictogen (As, Sb, and Bi) compounds and their transition metal complexes has led to the current surge in interest that led to significant development in the field of photophysical and optoelectronic properties of heavier pnictogens and their transition metal complexes. The presence of heavier pnictogens (As, Sb and Bi) in the molecular skeleton promotes inter-system crossing (ISC) and reverse inter-system crossing (RISC), because of the heavy atom effect, via altering the intermolecular interactions and orbital energy levels. As a result, π-conjugated heavier pnictogen compounds such as arsines, dibenzoarsepins, arsinoquinoline, heterofluorene, benzo[b]heterole (heterole=arsole, bismole, and stibole) show unique optoelectronic properties such as narrow bandgap, low-energy absorption, and long-wavelength emission than lighter pnictogen-based compounds.

Novel 1,2,3-triazolyl phosphine with a pyridyl functionality: synthesis, coinage metal complexes, photophysical studies and Cu(I) catalyzed C-O coupling of phenols with aryl bromides.

This manuscript describes the synthesis and coinage metal complexes of pyridine appended 1,2,3-triazolyl-phosphine [2-{(CHN)(C(PPh)NCH)}] (1), photophysical studies and their catalytic application. The reactions of 1 with copper salts afforded dimeric complexes [{Cu(μ-X)}{2-(CHN)(C(PPh)NCH)}] (2, X = Cl; 3, X = Br; and 4, X = I). The crystal structure indicates that the Cu⋯Cu distance in 4 (2.

Synthesis and Characterisation of Novel Bis(diphenylphosphane oxide)methanidoytterbium(III) Complexes.

Reaction of [YbCp(dme)] (Cp = cyclopentadienyl, dme = 1,2 dimethoxyethane) with bis(diphenylphosphano)methane dioxide (HdppmO) leads to deprotonation of the ligand HdppmO and oxidation of ytterbium, forming an extremely air-sensitive product, [Yb(HdppmO)] (), a six-coordinate complex with three chelating (OPCHPO) HdppmO ligands. Complex was also obtained by a redox transmetallation/protolysis synthesis from metallic ytterbium, Hg(CF) and HdppmO. In a further preparation, the reaction of [Yb(CF)] with HdppmO, not only yielded compound , but also gave a remarkable tetranuclear cage, [Yb(µ-HdppmO)(µ-F)] () containing two [Yb(µ-F)] rhombic units linked by two fluoride ligands and the tetranuclear unit is encapsulated by six bridging HdppmO donors.

A greener approach towards the synthesis of N-heterocyclic thiones and selones using the mechanochemical technique.

This manuscript describes the synthesis of N-heterocyclic thiones and selones of a variety of imidazolium salts involving an eco-friendly and solventless ball-milling technique. The products have been isolated in almost quantitative yield, involving a minimum quantity of solvents only for the isolation of products by column chromatography, and in some cases for purification purposes. Both mono- and bisimidazolium salts afforded N-heterocyclic thiones and selones.

Perception of Oral Health and Practices among Children Residing in Orphanages in Bengaluru.

Background: Children residing in orphanages often have accumulated oral health needs as they are unaware of the importance of maintaining good oral hygiene. Due to financial constraints, the provision of oral health care is often neglected.

Aims And Objectives: This study attempts to assess the perception of oral health and practices among children residing in orphanages in Bengaluru.

2,2'-Bipyridine derived doubly B ← N fused bisphosphine-chalcogenides, [CHN(BF){NCHP(E)Ph}] (E = O, S, Se): tuning of structural features and photophysical studies.

2,2'-Bipyridine based bisphosphine [CHN{N(H)CHPPh}] (1) and its bischalcogenide derivatives [CHN{N(H)CHP(E)Ph}] (2, E = O; 3, E = S; 4, E = Se) were synthesized, and further reacted with BF·EtO/EtN to form doubly B ← N fused compounds [CHN(BF){NCHP(E)Ph}] (5, E = O; 6, E = S; 7, E = Se) in excellent yields. The influence of the PE bonds on the electronic properties of the doubly B ← N fused systems and their structural features were investigated in detail, supported by extensive experimental and computational studies. Compound 6 exhibited a very high quantum yield of = 0.

Ru complexes of 1,2,3-triazole appended tertiary phosphines, [P(Ph){(-CH)(1,2,3-NC(Ph)CH}] and [P(Ph){-CH(CCH)-(1,2,3-N-Ph)}]: highly active catalysts for transfer hydrogenation of carbonyl/nitro compounds and for α-alkylation of ketones.

The synthesis of two new 1,2,3-triazole appended monophosphines [P(Ph){(-CH)(1,2,3-NC(Ph)CH}] (1) and [P(Ph){-CH(CCH)(1,2,3-N-Ph)}] (2) and their Ru complexes is described. The reactions of 1 and 2 with [Ru(PPh)Cl] in a 1 : 1 molar ratio produced cationic complexes 3 and 4, respectively. Both the complexes showed very high catalytic activity towards transfer hydrogenation, nitro reduction, and α-alkylation reactions and afforded the corresponding products in good to excellent yields.

1,2,3-Triazole based ligands with phosphine and pyridine functionalities: synthesis, Pd and Pt chemistry and catalytic studies.

This manuscript describes the syntheses of pyridine appended triazole-based mono- and bisphosphines, [-PhP(CH){1,2,3-NC(Py)C(H)}] (2), [-Br(CH){1,2,3-NC(Py)C(PPh)}] (3), [CH{1,2,3-NC(Py)C(PPh)}] (4), [PhP(CH){1,2,3-NC(Py)C(PPh)}] (5) and [3-PhP-2-{1,2,3-NC(Ph)C(PPh)}CHN] (6), their palladium and platinum chemistry and catalytic applications. These ligands upon treatment with [M(COD)Cl] (M = Pd or Pt) yielded complexes with different coordination modes, depending on the reaction conditions. Both κ-, and κ-, coordination modes were observed in many of the complexes indicating the ambidentate nature of these ligands.

Platinum Assisted Tandem P-C Bond Cleavage and P-N Bond Formation in Amide Functionalized Bisphosphine -PhPCHC(O)N(H)CHPPh-: Synthesis, Mechanistic, and Catalytic Studies.

The reactions of amide functionalized bisphosphine -PhPCHC(O)N(H)CHPPh- () with platinum salts are described. Treatment of with [Pt(COD)Cl] yielded a chelate complex, [PtCl{-PhPCHC(O)N(H)CHPPh-}] (), which on subsequent treatment with LiHMDS formed a novel 1,2-azaphospholene-phosphine complex [Pt(CH)Cl{-CH{C(O)N(-PPh(CH))P(Ph)}}] () involving a tandem P-C bond cleavage and P-N bond formation. The same complex on passing dry HCl gas afforded the dichloro complex [PtCl{-CH{C(O)N(-PPh(CH))P(Ph)}}] ().

Group 11 metal complexes of the dinucleating triazole appended bisphosphine 1,4-bis(5-(diisopropylphosphaneyl)-1-phenyl-1-1,2,3-triazol-4-yl)benzene.

The synthesis of a triazole appended dinucleating bisphosphine 1,4-bis(5-(diisopropylphosphaneyl)-1-phenyl-1-1,2,3-triazol-4-yl)benzene (2) and its coinage metal complexes are described. The dinucleating bisphosphine 2 was obtained by the temperature-controlled lithiation of 1,4-bis(1-phenyl-1-1,2,3-triazol-4-yl)benzene (1a) and 1,4-bis(1-(2-bromophenyl)-1-1,2,3-triazol-4-yl)benzene (1b) followed by the reaction with PrPCl. The reactions of 2 with copper(I) halides in 1 : 2 molar ratios yielded the [Cu(μ-X)] dimeric complexes [{Cu(μ-X)}(PPrNPhC)CH] (3, X = Cl; 4, X = Br; and 5, X = I), whereas the reaction of 2 with AgBr resulted in the formation of hetero-cubane complex [{Ag(μ-Br)}{(PPrNPhC)CH}] (7).

Synthesis, structural, characterization and Hirshfeld analysis of a bisselenide and a zinc complex of a new hemilabile ferrocenylbisphosphane, [Fe{CHP(CHCHNMe-o)}].

The novel hemilabile ferrocenylbisphosphane 1,1'-bis(bis{2-[(dimethylamino)methyl]phenyl}phosphanyl)ferrocene, [Fe{CHP(CHCHNMe-o)}] (1), was synthesized by reacting bis(dichlorophosphanyl)ferrocene, [Fe{CH(PCl)}] with LiCHCHNMe-o. Treatment of 1 with gray selenium and anhydrous ZnCl yielded, respectively, the bisselenide (ferrocene-1,1'-diyl)bis(bis{2-[(dimethylamino)methyl]phenyl}phosphine selenide), [Fe(CHNPSe)] (2), and the dizinc complex [μ-1,1'-bis(bis{2-[(dimethylamino)methyl]phenyl}phosphanyl)ferrocene-κN,P:κN',P']bis[dichloridozinc(II)] dichloromethane monosolvate, [FeZnCl(CHNP)]·CHCl (3), and both have been structurally characterized. Both compounds crystallized with the asymmetric unit containing half a molecule and with the Fe atom on an inversion centre.