Treatment of 1,4-dihydridooctaphenyltetrasilane, HzSi4(C6H5)8, with bis(triphenylphosphine)ethyleneplatinum(O), [ (C&)3P]zPtCzH4, affords the first example of a transition metal incorporated into a silicon ring, [ (C,#S)~P]~-Pt[Si(C6Hs)z] $i(C6H5)2. Infrared and ultraviolet spectroscopic examinations are reported and compared with similar data recorded for [ ( C & )~P ]~P~C Z H~, Si4(C6H&, and Sis(C6H5)lo. Attempts at several alternate methods of synthesis are discussed as well as reaction of the cyclo-metallosilane with Brz and Hz.

Methods for the preparation of aluminum trihydride-diethyl etherate, AlH, -0.3 [ (C, H5 )2 01 ,$ have been published,'S2 but the absence of complete experimental details makes duplication difficult. The following procedure is a modification of that reported by Finholt, Bond, and Schlesinger.' Problems inherent in previous methods, such as premature precipitation, decomposition of the alane, and lithium chloride contamination, are avoided.Premature precipitation is controlled by maintaining a low temperature (-5'C.) in the reaction mixture. Purified reactants, as well as minimal exposure to light and higher temperatures, *The Dow Chemical Company, Midland, Mich. 48640. This work was supported by +Ohio State University, Columbus, Ohio 43210. SEbdiometric molecular weight determinations obtained in diethyl ether (concentration range, 0.25-1.0 M ) indicates molecular weights only slightly higher than 30. This is consistent with studies reported by Wiberg and U~o n .~ It must be assumed that in solution, AM, exists essentially as the monomeric form.ARPA and the Air Force under contracts AF 33(616)-6149 and AF 04(611)-7554.

No abstract

Die Umsetzung des Dihydrotetrasilans (I) mit dem Pt(O)‐ Komplex (II) führt zu dem Titelkomplex (III), der der erste Vertreter eines Si‐Ringes mit einem Übergangsmetall ist.

Die relative Geschwindigkeit und der Umfang der Spaltung der Si‐Si‐Bindungen in Oktaphenyl‐ und Okta‐p‐tolylcyclotetrasilan (I) bzw. (IV) durch Li werden bestimmt.