2- and 3-arylpropyl(ethynyl)dimethylsilanes

Hydrosilylation of ortho- and para-substituted 2-phenylpropenes and ortho-, meta-, and para-alkoxysubstituted 3-phenylpropenes with chlorodimethylsilane in the presence of H₂PtCl₆ was effected. The resulting adducts were reacted with ethyntlmagnesium bromide to synthesize 2- and 3-arylpropyl(ethynyl)silanes.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 12, 2004, pp. 2003–2006.Original Russian Text Copyright © 2004 by O. Yarosh, Zhilitskaya, N. Yarosh, Albanov, Voronkov.This revised version was published online in April 2005 with a corrected cover date.     

Analysis of coefficient identification problems associated to the inverse Euler-Bernoulli beam theory

A rigorous investigation of the identification of a heterogeneousflexural rigidity coefficient in the Euler-Bernoulli steady-statebeam theory in the presence of a prescribed load is presented.Mathematically, this study is an extension to higher-order differentialequations of the coefficient identification problem analysedby Marcellini (1982) for the one-dimensional Poisson equation.In addition, various types of boundary conditions are discussed.Conditions for the well-posedness of these inverse problemsare established and, furthermore, numerical results obtainedusing a regularization algorithm are presented.     

A critical investigation of the effects of the radio frequency potential on the trapping of externally injected ions in ion trap mass spectrometry

The sensitivity of all ion trap mass spectrometry (ITMS) methods is dependent on the trapping efficiency of the instrument. For ITMS instruments utilizing external ion sources, such as laser desorption, trapping efficiency is known to depend on the phase and amplitude of the radio frequency (RF) potential applied to the ring electrode at the time of ion introduction. It is remarkable that, in a considerable body of literature, no consensus exists regarding the effects of these parameters on the efficacy of trapping externally generated ions. In this paper, a summary of the literature is presented in order to highlight significant discrepancies. New laser desorption ion trap mass spectrometry (LD-ITMS) data are also presented, from which conclusions are drawn in our effort to clarify some of the confusion. Copyright 1999 John Wiley & Sons, Ltd.     

Characteristic features of cyclotrimerization of perfluoroalkyl- and perfluorooxaalkylacetylenes

Cyclotrimerization of perfluoroalkyl- and perfluorooxaalkylacetylenes has been studied under various conditions. A scheme of the reaction mechanim has been suggested.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1789–1792, October, 1994.     

Reaction of sodium trimethylsilylacetylide with alkoxychlorosilanes and methylalkoxychlorosilanes

Conclusions Sodium trimethylsilylacetylide reacts with alkoxychlorosilanes and methylalkoxychlorosilanes to give alkoxy(trimethylsilylethynyl)silanes and methylalkoxy(trimethylsilylethynyl)silanes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1674–1675, July, 1973.     

Synthesis and properties of fluorosilicon compounds for protection of cultural monuments from harmful environmental exposure

Methods for the synthesis of perfluorocarboxylic acid derivatives with reactive trialkoxysilyl groups soluble in organic and organofluorine (1,1,2-trichlorotrif1uoroethane, etc.) solvents have been developed. The contact angles of water and decalin, water absorption, resistance to freezing, and salt-resistance of limestone and plaster samples treated with these compounds were determined. Fluorosilicon organic compounds impart more hydro- and oleophobic properties to the protected surfaces than known organosilicon agents and reliably protect sculptures and architectural monuments from mold and algae deposition.     

Synthesis of biologically active derivatives of 2-aminobenzothiazole

Chemistry of Heterocyclic Compounds - The minireview considers the current trends in the synthesis of some biologically active compounds based on 2-aminobenzothiazole. The presented information...     

Synthesis of secondary silicon-containing acetylenic alcohols of the thiophene series

New silicon-containing acetylenic alcohols of the thiophene series have been obtained by the reaction of trialkylsilylacetylenylmagnesium bromides with 2-thiophenealdehydes. Their addition to butyl vinyl ether has given the corresponding acetals.