Synthesis, Structural Characterization and Reactivity of the (Ferriomethyl)silanols C5R5(OC)2Fe−CH2−SiMe(R′)OH (R = H, Me; R′ = Me, Ph)

Abstract

The novel (ferriomethyl)-substituted silanols C5R5(OC)2Fe−CH2−SiMe(R′)OH [R = H, R′ = Me (4a), Ph (4b); R = Me, R′ = Me (4c)] are obtained by hydrolysis of the chloro(ferriomethyl)silanes C5R5(OC)2Fe−CH2−SiMe(R′)Cl [R = H, R′ = Me (3a), Ph (3b); R = Me, R′ = Me (3c)] in the presence of Et3N. Another access to this class of compounds is offered by the oxygenation of Si−H-functional (ferriomethyl)silanes with dimethyldioxirane, as shown for 4a by the oxo-functionalization of the (ferriomethyl)silane Cp(OC)2Fe−CH2−SiMe2H (3d). 4a−c have been characterized spectroscopically and by X-ray structure analyses showing the formation of tube- or chain-like arrangements in the solid state caused by hydrogen bonding. In addition, the bonding situation in the related (ferriomethyl)silanol Cp(OC)2Fe−CH2−SiH2OH has been analyzed on the basis of density functional calculations. 4a shows self-condensation to give the 1,3-bis(ferriomethyl)disiloxane [Cp(OC)2Fe−CH2−SiMe2]2O (5), which is also obtained by the reaction of 4a with 3a. Analogous treatment of 4a with the chloro(organo)silanes R(R′)Si(Me)Cl (R = H, R′ = Me, p-Tol; R = R′ = Me) yields the monometalated disiloxanes Cp(OC)2Fe−CH2−Si(Me)2OSi(Me)(R)R′ [R = H, R′ = Me (6a), p-Tol (6b); R = R′ = Me (6c)]. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)