Insertion of SnCl2 into Pt–Cl bonds: synthesis and characterization of four- and five-coordinate trichlorostannylplatinum(II) complexes

Rational Syntheses and Serendipity: Complexes [LSnPtCl2 (SMe2 )]2 , [{LSnPtCl(SMe2 )}2 SnCl2 ], [(LSn)3 (PtCl2 )(PtClSnCl){LSn(Cl)OH}], and [O(SnCl)2 (SnL)2 ] with L=MeN(CH2 CMe2 O)2

Syntheses and molecular structures of the dimeric tin-platinum complex [LSnPtCl₂ (SMe₂ )]₂ (2), the tin-platinum clusters [{LSnPtCl(SMe₂ )}₂ SnCl₂ )] (3) and [(LSn)₃ (PtCl₂ )(PtClSnCl)(LSnOHCl)] (6) (L=MeN(CH₂ CMe₂ O^- )₂ ), and of the unprecedented tin(II) aminoalkoxide-tin oxide chloride complex [O(SnCl)₂ ⋅(SnL)₂ ] (5) are reported. The compounds were characterized by NMR spectroscopy (¹ H, ¹³ C, ¹¹⁹ Sn, ¹⁹⁵ Pt), ¹¹⁹ Sn Mössbauer spectroscopy (1-3, 6), electrospray ionization mass spectrometry, elemental analyses, and single-crystal X-ray diffraction analyses (2⋅CH₂ Cl₂ , 3⋅2 C₄ H₈ O, 5, 6⋅3CH₂ Cl₂ ). The tin(II) aminoalkoxide [MeN(CH₂ CMe₂ O)₂ Sn]₂ (1) behaves like a neutral ligand, inserts into a Pt-Cl bond, or is involved in rearrangement reactions with the different behavior occurring even within one compound (3, 6). DFT calculations show that the tin-platinum compounds behave like electronic chameleons.

Platinum carbonyl clusters stabilized by Sn(ii)-based fragments: syntheses and structures of [Pt6(CO)6(SnCl2)2(SnCl3)4]4−, [Pt9(CO)8(SnCl2)3(SnCl3)2(Cl2SnOCOSnCl2)]4−and [Pt10(CO)14{Cl2Sn(OH)SnCl2}2]2−

Low valent Pt carbonyl clusters decorated by Sn(ii) fragments have been obtained from [Pt₁₅(CO)₃₀]²⁻and SnCl₂.

Tuneable reactivity with PPh3 and SnX2 of four- and five-coordinate Pd(II) and Pt(II) complexes containing polyphosphines

The reactivity of the unusual d(8) trigonal-bipyramidal systems [MX(PP3)]X (X = Cl: M = Pd(1a), Pt(2a); X = Br: M = Pd(3a), Pt(4a); X = I: M = Pd(5a), Pt(6a); PP3 = tris[2-(diphenylphosphino)ethyl]phosphine) in CHCl3-CH3OH, the square-pyramidal compounds [MCl(NP3)]Cl (M = Pd(7a); Pt(8a); NP3 = tris[2-(diphenylphosphino)ethyl]amine) in CD3OD-DMF and the distorted square-planar mononuclear [MX(PNP)]X (M = Pd: X = Cl(10a); M = Pt: X = I(10b); PNP = bis[2-(diphenylphosphino)ethyl]amine) and the heteronuclear [PdAu2X4(PP3)] [X = I(9a), Cl(14a), Br(15a)] and [MAuX2(PP3)]X [M = Pd: X = Cl(16a); M = Pt: X = Cl(17a), Br(18a)] species in CDCl3 with PPh3 + SnX2 has been explored to establish the factors that influence the nature of the products. With the mononuclear precursors the course of the reaction is strongly dependent on the tripodal or linear arrangement of the polydentate ligand and in the former case on the halogen. Thus, while for chlorides (1a-2a, 7a-8a) and bromides (3a-4a) the reaction led to the trigonal-bipyramidal compounds [M(SnCl3)(AP3)][SnCl3] [A = P: M = Pd(1), Pt(2); A = N: M = Pd(7), Pt(8)], [MBr(PP3)][SnBr3] [M = Pd(4), Pt(6)] containing M-Sn and M-Br bonds, respectively, for iodides (5a-6a) resulted in the unknown neutral square-planar compounds [MI2(PP(PO)2)(SnI2)2] [M = Pd(9) and Pt(10)] bearing two dangling P=O-SnI2 units and P2MI2 environments. However, complexes of the type [PtCl(PP2PO)X]X' [X = SnCl2, X' = [SnCl3](-)(11)] and [M(PP(PO)2)2X4]X'2 [X = SnCl2, X' = [SnCl3](-): M = Pd(12), Pt(13)] showing P=O-SnCl2 arms were obtained by direct reaction of [PtCl(PP2PO)]Cl (11a) and [M(PP(PO)2)2]Cl2 [M = Pd(12a), Pt(13a)] with SnCl2 in CH3OH. Although complex 9 was also prepared by interaction of the heteronuclear iodide 9a with PPh3 + SnI2 in CDCl3, the use of the neutral and ionic heteronuclear chlorides and bromides (14a-18a) as starting materials afforded the distorted square-planar ionic systems [MAuX'(PP3)(PPh3)][SnX3]2 [M = Pd: X = Cl, X' = SnCl3(-)(14); X = Br, X' = SnBr3(-)(15); M = Pt: X = Cl, X' = SnCl3(-)(17); X = Br, X' = SnBr3(-)(18)] containing M-SnX3 and P-Au-PPh3 functionalities. It was found that these reactions where the heteronuclear species are the precursors proceed via the trigonal-bipyramidal halides not only with X = Cl and Br(1a-4a) but also I(5a). When the precursors were 10a and 10b the reaction occurred with formation of [Pd(PNP)(PPh3)][SnCl3]2 (23) and [Pt(PNP)(PPh3)][SnCl2I]2 (24) showing M-PPh3 units and trihalostannato counter anions.

Micellar Catalysis on Pentavalent Vanadium Ion Oxidation of Ethanol in Aqueous Acid Media

Vanadium(V) oxidation of ethanol follows a first order dependency on the concentration of ethanol, vanadium(V), H+ and HSO4 –. These observations remain unaltered in the presence of externally added surfactants. The effect of the cationic surfactant (i.e., N-cetylpyridinium chloride [CPC]), anionic surfactant (i.e., sodium dodecyl sulphate [SDS]) and neutral surfactant (i.e., Triton X-100 [TX-100]) has been studied. CPC inhibits the reactions, whereas SDS and TX-100 accelerate the reaction to different extents. Observed effects have been justified by considering the hydrophobic and electrostatic interaction between the surfactants and reactants. SDS and TX-100 can be used as catalysts in the production of acetaldehyde from ethanol.