0000000000194959
AUTHOR
Hans Preut
Synthesis and spectroscopic characterization of diethyltin (IV) derivatives of dipeptides: Crystal and molecular structure of diethyltin glycyltrosinate
Dipeptide complexes of the diethyltin(IV) moiety, Et2SnL, have been synthesized, H2L being glycylglycine (H2GlyGly), glycylalanine (H2GlyAla), alanylalanine (H2AlaAla), glycylvaline (H2GlyVal), valylvaline (H2ValVal), glycylmethionine (H2GlyMet), glycyltyrosine (H2GlyTyr). The crystal and molecular structure of the complex Et2SnGlyTyr has been determined by singlecrystal X-ray diffraction. It consists of monomeric units, with the tin atom having a considerably distorted trigonal bipyramidal environment. The dipeptide acts as a tridentate ligand bonding the tin of the C2Sn fragment (equatorial carbon atoms) with the peptide nitrogen atom (equatorial) and axial (monodentate) carboxyl oxygen a…
Mössbauer spectroscopic studies of clusters Mn2(CO)8[μ-Sn(hal)Mn(CO)5]2 (hal = Cl, Br) and related Mn and Re compounds
Abstract In order to be acquainted with the nature of bonds at Sn involved in the title compounds, as well as to get information on the configuration of the strictly related derivatives I2Sn2Mn4(CO)18 and Cl2Sn2Re4(CO)18, the Mossbauer spectroscopic investigation reported in this paper has been carried out. The experimental parameters (isomer shifts, δ; nuclear quadrupole splittings, ΔE; for the bromide derivative only, the asymmetry parameter η and the sign of the nuclear quadrupole coupling constant e2qQ) have been discussed in connection with data concerning compounds with tin-transition metal bonds, mainly hal2Sn[Mn(CO)5]2 (hal = Cl, Br) and ClSn[Mn(CO)5]3. Rationalizations of ΔE and η …
Synthesis and spectroscopic characterization of dimethyl-, di-n-butyl-, di-t-butyl-and diphenyl-tin(iv) derivatives of dipeptides: Crystal and molecular structure of di-n-butyltin(iv) glycylvalinate
The dipeptide complexes R2SnL listed below have been synthesized: (a) Me2SnL; H2L = glycylalanine (H2GlyAla), glycylvaline (H2GlyVal), glycylmethionine (H2GlyMet), glycyltryptophan (H2GlyTrp), glycyltyrosine (H2GlyTyr); (b) nBu2SnL; H2L = H2GlyAla, H2GlyVal; (c) nBu2SnL.H2O; H2L = glycylglycine (H2GlyGly), H2GlyAla; (d) tBu2SnL; H2L = H2GlyAla, H2GlyVal; (e) tBu2SnGlyGly. H2O; (f) Ph2SnL; H2L = H2GlyAla, H2GlyVal, H2GlyTyr, H2GlyTrp; (g) Ph2Sn(HGlyVal)2. The crystal and molecular structures of nBu2SnGl Val have been determined by single-crystal X-ray diffraction. The polyhedron around tin is a distorted trigonal bipyramid, analogous to that of Et2SnGlyTyr (see Vornefeld et al., Appl. Organo…
X-ray crystal structure and antimony-121 Mössbauer spectrum of catecholato bis(1,10-phenanthroline)antimony(III) tetraphenylborate
The crystal structure of the title compound was solved by means of X-ray diffraction at room temperature. The salt consists of a tetrahedral tetraphenylborate anion and a complex cation containing a catecholatoantimony(III) unit chelated by two 1,10-phenanthrolines. The three bidentate ligands are essentially arranged in one half of the Sb coordination sphere, leaving ample space to accomodate the lone pair of electrons. The Mossbauer parameters of the title compound and of the complex (C6H4O2)SbF·Phen were measured and their rationalization accomplished in the light of their respective molecular structures.
Synthesis and spectroscopic characterization of dicyclohexyltin derivatives of dipeptides, andin vitro effects against MDA-MB 231 breast cancer cells: Crystal structures of dicyclohexyltin glycylglycinate and glycylalaninate
Dicyclohexyltin derivatives Cy2SnL (Cy = cyclohexyl) of the dipeptides H2L, glycylglycine, glycylalanine, alanylglycine, glycylvaline, glycylmethionine, glycylphenylalanine and glycyltyrosine, have been obtained by neutralization of Cy2SnO and H2L. The crystal structures of Cy2SnL (L = glycylglycinate, glycylalaninate) have been determined by single X-ray diffraction. Tin in each case has a distorted trigonal bipyramidal environment with the dipeptide acting as a tridentate NNO-ligand. From IR-data, and in some cases from 119Sn Mossbauer and 119Sn NMR data, analogous molecular structures are inferred for the other compounds Cy2SnL. Spectroscopic data indicate that the solid-state structures…
Synthesis and characterization of diorganotin(IV) derivatives of 2-mercaptopyridine and crystal structure of diphenyl pyridine-2-thiolatochlorotin(IV)
Diorganotin(IV) derivatives of 2-mercaptopyridine (HSPy), R2Sn(SPy)2, R2SnCl(SPy) (R = Me, iPr, nBu, tBu, Cy, Ph) and Cy2SnBr(SPy), were obtained from R2SnX2 (X = Cl, Br) and NaSPy. Ph2SnCl(SPy) crystals, as determined by singlecrystal X–ray diffraction, are monoclinic in the space group P21/n. Tin forms with the bidentate SPy ligand a four–membered chelate ring with a short NSnS bite angle of 64.8(1)° leading to a heavily distorted trigonal–bipyramidal environment about tin. Apical Cl–Sn–N angle = 156.1(1)° equatorial C–Sn–C angle = 121.9(2)°. From 119Sn Mossbauer and IR data, analogous structures are inferred for the other solid compounds R2SnX(SPy), and distorted octahedral molecular str…
ChemInform Abstract: Synthesis and Characterization of Diorganotin(IV) Derivatives of 2- Mercaptopyridine and Crystal Structure of Diphenyl Pyridine-2- thiolatochlorotin(IV).
Diorganotin(IV) derivatives of 2-mercaptopyridine (HSPy), R2Sn(SPy)2, R2SnCl(SPy) (R = Me, iPr, nBu, tBu, Cy, Ph) and Cy2SnBr(SPy), were obtained from R2SnX2 (X = Cl, Br) and NaSPy. Ph2SnCl(SPy) crystals, as determined by singlecrystal X–ray diffraction, are monoclinic in the space group P21/n. Tin forms with the bidentate SPy ligand a four–membered chelate ring with a short NSnS bite angle of 64.8(1)° leading to a heavily distorted trigonal–bipyramidal environment about tin. Apical Cl–Sn–N angle = 156.1(1)° equatorial C–Sn–C angle = 121.9(2)°. From 119Sn Mossbauer and IR data, analogous structures are inferred for the other solid compounds R2SnX(SPy), and distorted octahedral molecular str…
Complexes of organometallic compounds
Abstract Novel complexes RClSntrid, where R is Me, Ph, n-Oct, and trid 2− are dianions of tridentate “planar” ligands with ONO and SNO donor atoms, were synthesized and investigated in the solid state by infrared and Mossbauer spectroscopy. Possible configurations are discussed; polymeric trigonal bipyramidal structures seem to occur, although five-coordinated monomers as well as octahedral dimers (via oxygen or sulfur bridges) are not excluded.