0000000000367682

AUTHOR

Claudio Pettinari

0000-0002-2547-7206

Characterization of diorganotin(IV) complexes with captopril. The first crystallographically authenticated metal complex of this anti-hypertensive agent

Abstract Diorganotin(IV) complexes R 2 Sn(cap) (capH 2 = N -[( S )-3-mercapto-2-methylpropionyl]- l -proline; R=Me, Et, n -Bu and t -Bu) were prepared and characterised. The FTIR and Raman spectra demonstrated that the organotin(IV) moieties interact with the {S} atom of the ligand, while the other coordination sites are the carboxylate and the amide –CO groups. Mossbauer Δ data showed that the diorganotin(IV) compounds adopt slightly distorted trigonal-bipyramidal (tbp) geometry. A single-crystal X-ray study was performed on the compound Me 2 Sn(cap): the Sn atom is five-coordinated in a distorted tbp environment, with two {O} atoms in the axial positions and the {S} and two {C} atoms in t…

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Synthesis and characterization of the first diorganotin(IV) complexes containing mixed arylazobenzoic acids and having skew trapezoidal bipyramidal geometry

Abstract Three diorganotin(IV) complexes of the type, [R 2 Sn(L a H)(L b H)] (R =  n Bu or Me and, L a H and L b H are two different 5-[( E )-2-(aryl)-1-diazenyl]-2-hydroxybenzoate residues; a: aryl = 4′-Cl-(held constant) and b: aryl = 4′-Me or 4′-Br) have been prepared either by reacting n Bu 2 SnO, L a HH′ and L b HH′ (1:1:1) in anhydrous toluene or by reacting Me 2 SnCl 2 , L a HNa and L b HNa (1:1:1) in anhydrous methanol. The products were characterized by microanalysis, IR, NMR ( 1 H, 13 C, 119 Sn) and 119m Sn Mossbauer spectroscopy. A full characterization of the structures of the complexes [ n Bu 2 Sn(L a H)(L b H)] ( 1 and 2 ) and [Me 2 Sn(L a H)(L b H)] ( 3 ) in the solid state w…

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Synthesis and Structures of Two Triorganotin(IV) Polymers R3Sn{O2CC6H4[N=C(H)}{C(CH3)CH(CH3)-3-OH]-p} n (R = Me and Ph) Containing a 4-[(2Z)-(3-Hydroxy-1-methyl-2-butenylidene)amino] benzoic Acid Framework

Two new polymeric triorganotin(IV) complexes R3Sn{O2CC6H4[N=C(H)}{C(CH3)CH(CH3)-3-OH]-p} n ([Me3Sn(LH)] n : 1) and ([Ph3Sn(LH)] n : 2) containing a 4-[(2Z)-(3-hydroxy-1-methyl-2-butenylidene)amino]benzoate (LH) framework were prepared. Both compounds have been characterized by 1H, 13C, 119Sn NMR, IR and 119Sn Mossbauer spectroscopic techniques in combination with elemental analyses. The crystal structures of complexes 1 and 2 reveal that they exist as polymeric zig-zag chains in which the LH-bridged Sn-atoms adopt a trans-R3SnO2 trigonal bipyramidal configuration with R groups in the equatorial positions and the axial sites occupied by an oxygen atom from the carboxylate ligand and the alco…

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Di-n-octyltin(IV) complexes with 5-[(E)-2-(aryl)-1-diazenyl]-2-hydroxybenzoic acid: Syntheses and assessment of solid state structures by 119Sn Mössbauer and X-ray diffraction and further insight into the solution structures using electrospray ionization MS, 119Sn NMR and variable temperature NMR spectroscopy

Abstract Reactions of 5-[( E )-2-(aryl)-1-diazenyl]-2-hydroxybenzoic acids (LHH′, where the aryl group is an R-substituted phenyl ring such that for L 1 HH′: X = H; L 2 HH′: X=2′-OCH 3 ; L 3 HH′: X = 3′-CH 3 ; L 4 HH′: X = 4′-CH 3 ; L 5 HH′:X = 4′-Cl) with n Oct 2 SnO in 2:1 and 1:1 molar ratios have been investigated. Two types of complexes, n Oct 2 Sn(LH) 2 and {[ n Oct 2 Sn(LH)] 2 O} 2 , were isolated and they have been characterized by 1 H, 13 C, 119 Sn NMR, ESI-MS, IR and 119m Sn Mossbauer spectroscopic techniques in combination with elemental analyses. The crystal structures of n Oct 2 Sn(L 1 H) 2 ( 1 ), {[ n Oct 2 Sn(L 2 H)] 2 O} 2 ( 3 ) and {[ n Oct 2 Sn(L 3 H)] 2 O} 2 ( 4 ) were de…

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Tin(IV) and organotin(IV) derivatives of bis(pyrazolyl)acetate: Synthesis, spectroscopic characterization and behaviour in solution.

Abstract Novel heteroscorpionate-containing tin and organotin(IV) complexes, [SnRnX3 − n(L)], R = Me, Bun, Ph, or cy; X = Cl, Br or I, n = 0, 1, 2 or 3; L = bis(pyrazol-1-yl)acetate (bpza) or bis(3,5-dimethylpyrazol-1-yl)acetate (bdmpza), have been synthesized and characterized by spectral (IR, 1H, 13C and 119Sn NMR, 119mSn Mossbauer) and analytical data. In [SnI3(bdmpza)], the ligand is fac-N,N′,O-tridentate, the three iodine atoms thus also fac about the six-coordinate tin(IV) atom. Neutral bpzaH reacts with BunSnCl3, PhSnCl3 and SnCl4 in Et2O in the absence of base, yielding 1:1 adducts [XSnCl3(bpzaH)] (X = R or Cl).

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Synthesis and characterization of some diorganotin(IV) complexes of Schiff bases derived from a non-protein amino acid. Crystal structures of {HO2CC6H4[NC(H)}{C(CH3)CH(CH3)-3-OH]-p} and its di-n-butyltin(IV) complex (nBu2Sn{O2CC6H4[NC(H)}{C(CH3)CH(CH3)-3-OH]-p}2)

Diorganotin(IV) complexes R2Sn(LH)2 (R = Me, nBu) and {[nBu2Sn(LH)]2O}2 (LH = 4-[(2Z)-(3-hydroxy-1-methyl-2-butenylidene)amino]benzoate and 4-[{(E)-1-(2-hydroxyphenyl)methylidene}mino]benzoate) have been reported. The complexes were characterized by elemental analysis, IR, NMR (1H, 13C, 119Sn) and 119mSn Mossbauer spectroscopy. Crystal structures of a ligand {HO2CC6H4[NC(H)}{C(CH3)CH(CH3)-3-OH]-p} and one of its di-n-butyltin(IV) complexes (nBu2Sn{O2CC6H4[NC(H)}{C(CH3)CH(CH3)-3-OH]-p}2) were determined. The spectroscopic data suggest that R2Sn(LH)2 complexes have skew-trapezoidal bipyramidal structure while {[nBu2Sn(LH)]2O}2 complexes adopt a dimeric tetraorganodistannoxane structure in the…

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Coordination properties of the ACE inhibitor captopril towards Me2Sn(IV)2+ in aqueous solution, and biological aspects of some dialkyltin(IV) derivatives of this ligand

Abstract The coordination of Me 2 Sn(IV) 2+ (M) to captopril { N -[( S )-3-mercapto-2-methylpropionyl]- l -proline, H 2 (cap), H 2 L} in aqueous solution was studied by means of potentiometric titration, electrospray mass spectrometry, 1 H-NMR spectroscopy and Mossbauer spectroscopy in the pH range 2–11 ( I =0.1 mol dm −3 NaClO 4 , 298 K). The results obtained with these methods proved that only monomeric complexes are formed in solution. In the acidic pH range, species with a metal-to-ligand ratio of 1:1 exist. The neutral complex ML, similarly to the complex Me 2 Sn(cap) crystallized in the same pH range, adopts a tbp structure with eq S − and ax COO − , while, instead of the coordina…

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Tin(IV) and organotin(IV) complexes containing mono or bidentate N-donor ligands

Abstract A series of adducts of the type [(L # ) y R n SnX 4− n ]· z H 2 O (L # =1-methylimidazole, y =1 or 2, R=Me, Et, Bu n or Ph, n =1, 2 or 3, X=Cl, Br or I, z =0, 1/2 or 1) has been characterized in the solid state and in solution by analyses, spectral (IR, 119 Sn Mossbauer, and 1 H, 13 C and 119 Sn NMR) data and conductivity measurements. The molecular weight determinations and the NMR data indicate that these organotin(IV) complexes partly dissociate in chloroform and acetone solution. The donor L # interacts with [(CH 3 ) 3 SnNO 3 ], yielding the 2:1 ionic complex [(L # ) 2 (CH 3 ) 3 Sn]NO 3 . The derivative [(L # ) 2 (CH 3 ) 2 SnCl 2 ] reacts with NaClO 4 , AgNO 3 , NaBPh 4 and KSC…

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5-Amino-1-phenyl-3-trifluoromethyl-1H-pyrazole-4-carboxylic acid

In the title compound, C11H8F3N3O2, there are two molecules in the asymmetric unit wherein the phenyl rings make dihedral angles of 65.3 (2) and 85.6 (2)° with the pyrazole rings. In the crystal, pairs of molecules are held together by O—H...O hydrogen bonds between the carboxyl groups, forming a centrosymmetric dimer with an R22(8) motif. Intramolecular N—H...O interactions are also present.

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Tin( II ) and Lead( II ) 4‐Acyl‐5‐pyrazolonates: Synthesis, Spectroscopic and X‐ray Structural Characterization

Novel tin(II) β-diketonate Sn(Q)2 complexes [HQ = 1-R1-3-R3-4-R4(C=O)-pyrazol-5-one; HQC: R1 = Ph, R3 = Me, R4 = Cy; HQS: R1 = Ph, R3 = Me, R4 = CHPh2; HQL: R1 = Ph, R3 = Me, R4 = CH2Ph; HQT: R1 = Ph, R3 = Me, R4 = CH2tBu; HQE: R1 = Ph, R3 = Me, R4 = Et; HQB: R1 = Ph, R3 = Me, R4 = tBu; HQW: R1 = Ph, R3 = Me, R4 = p-(tBu)Ph; HQR: R1 = Ph, R3 = Me, R4 = p-[(CH2)5CH3]Ph; HQN: R1 = p-NO2Ph, R3 = Me, R4 = Ph; HQM: R1 = Me, R3 = Me, R4 = Ph; HQD: R1 = Me, R3 = Me, R4 = Me; HQP: R1 = Ph, R3 = Ph, R4 = Ph; HQG: R1 = Ph, R3 = Ph, R4 = Me; HQF: R1 = p-CF3Ph, R3 = Me, R4 = Ph; HQH: R1 = p-CF3Ph, R3 = Me, R4 = Me] have been isolated and characterized by single-crystal X-ray diffraction analyses, IR, 1…

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