A method for making chlorinated silazanes. The method comprises contacting: (a) a disilazane; (b) a chlorosilane; and (c) a catalyst which is a zinc salt of: (i) a sulfonic acid or (ii) a sulfonic acid imide.

The invention relates to a method for cleaving silicon-silicon bindings and/or silicon-chlorine bindings in monosilanes, polysilanes, and/or oligosilanes. According to the invention, the monosilane, polysilane, and/or oligosilane is dissolved or suspended in an ether or in an ether-hydrochloric acid solution. Said method is used for example for preparing halogenated oligosilanes from halogenated polysilanes and for preparing siloxanes from organochlorosilanes and chlorinated monosilanes. Said method is particularly simple to carry out and as a result is economical.

The invention relates to a method for purifying halogenated oligosilanes in the form of a pure compound or a mixture of compounds with respectively at least one direct SiSi bond, the substituents thereof being exclusively made from halogen or from halogen and hydrogen and in the composition thereof, the atomic ratio of the substituents:silicon is at least 3:2, by the action of at least one purification agent on the halogenated oligosilane and by isolating the halogenated oligosilanes with improved purity. According to prior art, halogenated monosilanes such as HSiCl.sub.3 are purified by treating with organic compounds, preferably polymers, containing amino groups, and are separated from said mixtures. Based on the contained amino groups, said method can not be used for halogenated oligosilanes as the secondary reactions lead to a decomposition of the products. The novel method is used to provide the desired products in a high yield and purity without using the amino groups.

A column includes a column head, a column sump and a tube-shaped column shell disposed therebetween, two or more reaction zones lying above each other which each accommodate a catalyst bed, in which catalyst beds chlorosilanes disproportionate into low-boiling silanes, which form an ascending stream of gas, and also into high-boiling silanes which form a downwardly directed stream of liquid, within the column shell and along the column axis, two or more rectificative separation zones, the reaction zones and the separation zones alternate along the column axis, the separation zones are configured such that the stream of gas and the stream of liquid meet in the separation zones, and the reaction zones are configured such that the downwardly directed stream of liquid is led through the catalyst beds, whereas the upwardly directed stream of gas passes the catalyst beds in spatial separation from the stream of liquid.

A method of making a trihalodisilane, the method comprising: combining a reductive effective amount of an alkylaluminum hydride, a halodisilane comprising at least 4 halogen atoms, and a solvent at a temperature <80? C. and reducing the halodisilane to form a reaction product mixture comprising a trihalodisilane and an alkylaluminum halide.

A method of hydrogenating a halosilane comprises: contacting a halosilane having the formula HaSiX(4-a), wherein a has a value of 0 to 4, and each X is independently a halogen atom and wherein if a is 0, the halosilane further comprises a hydrogen source, with a catalyst composition comprising at least two different metals, wherein the at least two different metals are selected from Cu and one of Co, Fe, Ni, and Pd; wherein the ratio of Cu to the second metal in the catalyst composition is 90:10 to 10:90; wherein the contacting is conducted at a temperature sufficient to hydrogenate a halosilane; and wherein an increase in the amount of halosilane hydrogenated is observed as compared to a method with a catalyst composition comprising one metal at the same overall loading of metal in the catalyst composition.

Provided are complexes useful in the conversion of chloro- and bromo-silanes to highly desired iodosilanes such as H.sub.2SiI.sub.2 and HSiI.sub.3, via a halide exchange reaction. The species which mediates this reaction is an iodide reactant comprising aluminum.

A controlled preparation of octachlorotrisilane and higher polychlorosilane such as DCTS and DCPS from monomeric chlorosilane, proceeds by exposing the chlorosilane to a nonthermal plasma and recycling chlorosilane that has not been converted to octachlorotrisilane into the plasma.

The invention relates to a process and an apparatus for preparation of polychlorosilanes from monomeric chlorosilanes, by subjecting the chlorosilanes to a thermal plasma.

A column includes a column head, a column sump and a tube-shaped column shell disposed therebetween, two or more reaction zones lying above each other which each accommodate a catalyst bed, in which catalyst beds chlorosilanes disproportionate into low-boiling silanes, which form an ascending stream of gas, and also into high-boiling silanes which form a downwardly directed stream of liquid, within the column shell and along the column axis, two or more rectificative separation zones, the reaction zones and the separation zones alternate along the column axis, the separation zones are configured such that the stream of gas and the stream of liquid meet in the separation zones, and the reaction zones are configured such that the downwardly directed stream of liquid is led through the catalyst beds, whereas the upwardly directed stream of gas passes the catalyst beds in spatial separation from the stream of liquid.