Silanones theoretical studies

Alternative routes of nonhydrolytic conversion of chlorosilanes into siloxanes are also known. The most common one uses dimethyl sulfoxide (DMSO) as the oxygen source. Another useful method of the siloxane bond formation is the reaction of dichlorodiorganylsilanes with some metal oxides, such as ZnO (eqn [3]). The reaction is particularly useful for the synthesis of cydotrisiloxanes, which are rather difficult to prepare in any other way. By this method they can be obtained with the yield 30-60%. The mechanism of this transformation was recently studied by theoretical methods indicating that the reaction involves insertion of -Zn-O- into the Si-Cl bond. An alternative pathway involving transient silanone was shown to be much less thermodynamically feasible. 

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