V. I. Shcherbakov

Trialkyltin Derivatives of N-Phthaloyl-Protected Amino Acids

Abstract Thirty four new complexes of the type R3SnL (R = Alk and L = N-protected amino acid) have been prepared by the reaction of the trialkyltin oxide(hydroxide) and the corresponding N-phthaloyl amino acid in toluene and azeotropic removal of the liberated water. These compounds have been characterized by elemental analyses, IR data and their fungicide activity has been evaluated.

CCDC 273135: Experimental Crystal Structure Determination

Related Article: L.N.Bochkarev, Yu.E.Begantsova, V.I.Shcherbakov, N.E.Stolyarova, I.K.Grigorieva, I.P.Malysheva, G.V.Basova, A.L.Bochkarev, Yu.P.Barinova, G.K.Fukin, E.V.Baranov, Yu.A.Kurskii, G.A.Abakumov|2005|J.Organomet.Chem.|690|5720|doi:10.1016/j.jorganchem.2005.07.035

Synthesis and Thermolysis of Tris(triethoxysiloxy)aluminum and Its Complexes with Potassium and Sodium Triethoxysilanolates

Reaction of potassium (or sodium) triethoxysilanolate with AlBr3 in benzene in a 3 : 1 or 4 : 1 ratio yields, respectively, tris(triethoxysiloxy)aluminum Al[OSi(OEt)33 or potassium (or sodium) tetrakis(triethoxysiloxy)aluminate M{Al[OSi(OEt)3]4} (M = K, Na). Single-stage thermolysis of tris(triethoxysiloxy)aluminum (200°C) and potassium tetrakis(triethoxysiloxy)aluminate (300°C), followed by annealing of the solid residues at 1000-1250°C, yields ceramic materials, which were examined by X-ray diffraction. The crystalline phase obtained from tris(triethoxysiloxy)aluminum is aluminum metasilicate Al6Si2O13 (mullite), and the product obtained from potassium tetrakis(triethoxysiloxy)aluminate is a mixture of aluminum orthosilicate Al2SiO5 (kyanite) and feldspar aluminosilicate KAlSi3O8 (microcline).

Lithiation of the tin-containing sulfone Me3SnCH2CH2CH2SO2C6H4CH3-4

The tin-containing sulfide Me3Sn(CH2)3-S-C6H5CH3-4 obtained by photoaddition of 4-toluene- thiol to allyltrimethyltin was oxidized with hydrogen peroxide to synthesize the tin-containing sulfone Me3Sn(CH2)3-SO2-C6H4CH3-4, the tin and sulfur atoms in which are separated by a trimethylene bribge. Treatment of the sulfone with butyllithium gave a first tin-containing lithium salt having a red-brown color. The exchange reaction of this salt with methyl iodide resulted in formation of two new isomeric tin-containing sulfones Me3SnCH2CH2CH(CH3)-SO2-C6H4CH3 and Me3Sn(CH2)3-SO2-C6H4CH2CH3 identified by 1HNMR spectroscopy. The latter result implies that the tin-containing sulfone is lithiated both by the methylene group adjacent to the sulfonyl group and by the toluene methyl group.

1H and13C NMR study of tin-containing sulfoxide, sulfimide, and sulfoximide

Sulfoxide RS(O)R′ (1), sulfimide RS(=NSO2Ar)R′ (2), and sulfoximide RS(O)(=NSO2Ar)R′ (3) (R=Me3Sn(CH2)3, R′=n-C5H11, Ar=4-C6H4Cl) were investigated by1H and13C NMR spectroscopy. Unlike 3, compounds 1 and 2 have a cyclic structure due to the intramolecular donor-acceptor S→Sn interaction.

Reaction of trimethyltin 1-pentanethiolate withN-chloro-N-sodium-4-chlorobenzenesulfonamide

The reaction of trimethyltin 1-pentanethiolate withN-chloro-N-sodium-4-chlorobenzenesulfonamide proceeds in anhydrous methanolvia the initial cleavage of the tin-sulfur bond (desulfurization process) and subsequent imination of the sulfenylamide group ofN-trimethylstannyl-N(1-pentyl) sulfenyl-4-chlorobenzenesulfonamide with a second molecule of the chloroamide.

Reactions of hexamethylditin and trimethyltin sulfide withN-thio-derivatives of phthalimide

The initial formation of organotin derivatives with Sn-S-N bonds in heterolytic reactions of hexamethylditin or trimethyltin sulfide withN-(chlorothio)phthalimide is suggested. Subsequent interaction of these compounds with sulfenyl chloride affordsN, N′-thioorN, N′-dithiobisphthalimide. Homolytic reaction of hexamethylditin withN, N′-dithiobisphthalimide also occursvia an organotin intermediate, which, in the absence of a nucleophilic reagent, eliminates sulfur and converts intoN-trimethylstannylphthalimide.