18421-48-2Relevant articles and documents
Selective synthesis and formation mechanisms of trans- and cis-benzoyl(carbamoyl)platinum(II) complexes coordinated with tertiary phosphine ligands
Huang, Li,Ozawa, Fumiyuki,Yamamoto, Akio
, p. 2612 - 2620 (1990)
trans-Pt(COPh)Cl(PPh3)2 (1) reacts with secondary amines under CO pressure (10 atm) at room temperature to give cis-Pt(COPh)(CONR2)(PPh3)2 complexes (NR2 = NMe2 (5a), N(CH2)4CH2 (5b), N(CH2)3CH2 (5c), NEt2 (5d)) exclusively, while the same amines react with trans-[Pt(COPh)(CO)(PPh3)2]BF4 (7) under a nitrogen atmosphere to afford trans-Pt(COPh) (CONR2) (PPh3)2 complexes (NR2 = NMe2 = NMe2 (6a), N(CH2)4CH2 (6b), N(CH2)3CH2 (6c), NEt2 (6d)). The isomerization of the trans-benzoylcarbamoyl complexes (6a-d) to their cis isomers (5a-d) in a neat solvent is a slow process, but the isomerization is significantly accelerated by addition of amine and CO. On the other hand, benzoylplatinum complexes coordinated with compact and basic PMe3 ligands, trans-Pt(COPh)Cl(PMe3)2 (2) and trans-[Pt(COPh)(acetone)(PMe3)2]BF4 (4), give trans-Pt(COPh)(CONR2)(PMe3)2 (9) exclusively on treatment with CO and the secondary amines. Complex 9 is inert to isomerization to its cis isomer. Formation pathways of irons- and cis-benzoyl(carbamoyl)platinum complexes and their trans-cis isomerization process are examined in detail, and a new type of isomerization pathway involving participation of added CO and amine is proposed.
Electrochemical generation and reactivity of bis(tertiary phosphine)platinum(0) complexes: A comparison of the reactivity of [Pt(PPh3)2] and [Pt(PEt3)2] equivalents
Davies, Julian A.,Eagle, Cassandra T.,Otis, Deborah E.,Venkataraman, Uma
, p. 1080 - 1088 (2008/10/08)
Electrochemical reduction of cis-[PtCl2(PR3)2] (R = Ph, Et) in CH3CN/C6H6 containing NBu4ClO4 at a Hg pool electrode generates [Pt(PR3)2] equivalents in solution. Where R = Ph, the [Pt(PR3)2] equivalent may be trapped by O2, O2/CO2, HCl, MeI, C6H5COCl, and RC≡CR (R = Ph, COOMe) but not by the less reactive substrate PhCl. Where R = Et, the [Pt(PR3)2] equivalent reacts with the NBu4+ cation to ultimately generate trans-[PtH(Cl)(PEt3)2]. Prolonged electrolyses cause reduction of trans-[PtH(Cl)(PEt3)2] leading to hydride attack on the CH3CN solvent and ultimately forming trans-[PtH(CH2CN)(PEt3)2]. In the presence of bases such as NBu3, trans-[PtH(CH2CN)(PEt3)2] is isomerized in CH3CN solution producing trans-[PtCN(CH3)(PEt3)2]. The use of electroinactive trapping agents such as PhCl or PhCN as cosolvents for the reduction of cis-[PtCl2(PEt3)2] allows trapping of the [Pt(PEt3)2] equivalents as trans-[PtPh-(X)(PEt3)2] (X = Cl, CN).
PLATINUM(II) TRICHLOROSTANNATE CHEMISTRY. ON THE IMPORTANCE OF THE Pt-Sn LINKAGE IN HYDROFORMYLATION CHEMISTRY AND A NOVEL PtC(OSnCl2)R-CARBENE
Ruegg, H. J.,Pregosin, P. S.,Scrivanti, A.,Toniolo, L.,Botteghi, C.
, p. 233 - 242 (2007/10/02)
The reaction of trans-PtCl(COR)(PPh3)2 (1) (R=a, C6H5; b, C6H4-p-NO2; c, C6H4-p-CH3; d, C6H4-p-OCH3; e, CH3; f, Et; g, Prn; h, Hexn; i, CH2CH2Ph; j, But) with SnCl2 and SnCl2 plus H2 are described.The reactions with SnCl2 alone afford a mixture of trans-Pt(SnCl3)(COR)(PPh3)2 (2), and trans-PtCl(PPh3)2 (3) with 3 having a tin-oxygen bond.For 1f, 1h and 1j, reactions with SnCl2 plus H2 give aldehydes and platinum(II) hydride complexes, whereas for 1b and 1d, no aldehydes are obtained.The significance of these results in relation to H2 activation in the hydroformylation reaction is discussed. 31 P, 119 Sn, 195 Pt and, in a few cases, 13 C NMR data are presented.
