6746-22-1Relevant academic research and scientific papers
Room-Temperature Palladium(II)-Catalyzed Direct 2-Arylation of Indoles with Tetraarylstannanes
Liu, Yuxia,Wang, Chao,Huang, Linjuan,Xue, Dong
supporting information, p. 1613 - 1618 (2020/09/15)
A palladium(II)-catalyzed direct 2-arylation of indoles by tetraarylstannanes with oxygen (balloon) as the oxidant at room temperature has been developed. Various tetraarylstannanes can be employed as aryl sources for 2-arylation of indoles in up to 89% yield, providing a practical and efficient catalytic protocol for accessing 2-arylindoles.
Central-atom size effects on the methyl torsions of group XIV tetratolyls
Ng, Maggie C. C.,Harper, Jason B.,Stampfl, Anton P. J.,Kearley, Gordon J.,Rols, Stephane,Stride, John A.
supporting information, p. 13018 - 13024 (2013/01/15)
The Group XIV tetratolyl series X(C6H4-CH 3)4 (X=C, Si, Ge, Sn, Pb) were studied by using inelastic neutron scattering to measure the low-energy phonon spectra to directly access the methyl-group torsional modes. The effect of increased molecular radius as a function of the size of the central atom was shown to have direct influence on the methyl dynamics, reinforced with the findings of molecular dynamics and contact surface calculations, based upon the solid-state structures. The torsional modes in the lightest analogue were found to be predominantly intramolecular: the Si and Ge analogues have a high degree of intermolecular methyl-methyl group interactions, whilst the heaviest analogues (Sn and Pb) showed pronounced intermolecular methyl interactions with the whole phonon bath of the lattice modes. Size matters! The size of the central atom in the Group XIV tetratolyls was shown to determine the solid-state structures courtesy of the effect that it has on the overall size of the molecules (see figure). Because the outer-most methyl groups enter into close intermolecular interactions (for the Si and Ge analogues), the structure is driven to lower symmetry; as a consequence, the smallest (C) and largest (Sn and Pb) analogues are isostructural. Copyright
Palladium(II)- and rhodium(III)-catalyzed carbonylation reaction of aryltin compounds
Uemura,Ohe,Motofusa,Ohe
, p. 1343 - 1348 (2007/10/03)
The Pd(II)- and Rh(III)-catalyzed carbonylation reaction of several aryltin compounds, i.e., tetraphenyltin (Ph4Sn), in acetonitrile (MeCN) and acetic acid was studied. The reaction of Ph4Sn with 1 atm of CO in the presence of a stoichiometric amount of Pd(II) salt was performed to confirm whether more than one of the four phenyl groups could be transferred to the products. To accelerate the carbonylation, LiCl was added, thus, producing benzophenone, benzoic acid, and a small amount of biphenyl as organic products, but only one of the four phenyl groups was transferred to the products. For the Rh(II)-mediated and -catalyzed carbonylation of aryltin compounds in MeCN, benzophenone was mainly produced together with benzoic acid and biphenyl. Seventy-five percent of the four phenyl groups were transferred to the products. The product yield was > 100% based on the amount of Rh(III) chloride used, showing that the Rh(III) salt itself worked as a catalyst without reoxidant addition. Thus, More than one of two, three, or four aryl groups of aryltin compounds, and almost all of them in some cases, could be transferred to the products in this catalytic carbonylation.
Palladium-catalyzed carbostannylation by means of reagents containing carbon-tin-halogen inter-element linkages
Fugami, Keigo,Kawata, Kentaro,Enokido, Tatsuki,Mishiba, Yukie,Hagiwara, Sachiko,Hirunuma, Yasuyuki,Koyama, Daisuke,Kameyama, Masayuki,Kosugi, Masanori
, p. 433 - 444 (2007/10/03)
Reagents containing carbon-tin-halogen inter-element linkages were effective for palladium-catalyzed carbostannylation. In situ generated allyltin trichlorides add to carbon-carbon double bonds of bicyclo[2.2.1]hept-2-ene (norbornene) and bicyclo[2.2.1]hepta-2,5-diene (norbornadiene), stereoselectively, under the catalysis of palladium(0) species in good yields. The regioselectivity of unsymmetrically substituted allylic reagents dramatically alters with the choice of the tin(II) salt. Aryltin trichlorides undergo palladium-catalyzed arylstannylation of norbornene, giving a mixture of products composed of that taking one norbornene and that taking two norbornenes. The product ratio is dependent on the choice of the solvent and electronic nature of the aromatic substituent.
Ueber Tetraaryl-Methan-Analoga in der Gruppe 14.III. Ar4Sn/Pb (Ar=Ph, p-, m-, o-Tol, 2,4-Xyl und 2,5-Xyl): Gegenueberstellung von Bindungslaengen und Winkeln, von NMR chemischen Verschiebungen und Kopplungskonstanten und von Schwingungsdaten
Schneider-Koglin, Claudia,Mathiasch, Bernd,Draeger, Martin
, p. 25 - 32 (2007/10/02)
The title compounds have been synthesized Grignard reactions or pyrolysis of diplumbanes respectively.The crystal structures of m-Tol4Pb and Ph4Pb (redetermination) have been determined.All eight compounds (Ph/Tol)4(Sn/Pb) are S4 symmetric and contracted along this unique axis.The 13C-NMR chemical shifts and the couplings 1J(119Sn/207Pb-13C) as well depend additively upon the methyl substituents.The ratios 1K(207Pb-13C):1K(119Sn-13C) of the reduced coupling constants are all near to 1.61; a comparison with values from the literature for alkyl, alkenyl and alkinyl substituents is given.The ratio δ(207Pb):δ(119Sn) results in 2.28.IR (700 down to 200 cm-1) and Raman (700 down to 50 cm-1) data are given.Key words: Tin; Lead; Group 14; Vibrational data; Nuclear magnetic resonance; Crystal structure
Preparation and Characterization of Bis-Dithiocarbamato di-p-Tolyl Tin(IV)
Wadhwa, Sangeeta,Garg, B. S.,Sharma, C. P.,Kumar, N.
, p. 247 - 250 (2007/10/02)
Bis-Dithiocarbamato di-p-tolyltin(IV), i.e., (p-CH3C6H4)2Sn(S2CNRR')2 (where R=R'=CH3, C2H5, i-C3H7; R=CH3, C2H5, i-C3H7 and R'=C6H5, CH2C6H5 or RR'=morpholine, 4-methylpiperidine and N-piperazine), were prepared by the reaction of di-p-tolyltin(IV) dichloride with the sodium salt of respective dithiocarbamate acid in acetone medium in the stoichiometric ratio of 1:2.The compounds have been duly characterized on the basis of infrared and nmr spectroscopic data.Anisobidentate nature of dithiocarbamate moiety has been suggested in these compounds.
