“Inverse Sandwich” Complexes of Perhalogenated Cyclohexasilane
摘要:
Perhalogenated cyclohexasilanes, Si6X12 (X = Cl, Br), were prepared by reaction of Si6H12 with molecular chlorine or bromine in cold (-89 degrees C) dichloromethane. Single-crystal structural determination by X-ray analysis shows that the six silicon atoms comprising Si6Br12 adopt a chair conformation in the solid state. The addition of p-tolunitrile to Si6X12 (X = Cl, Br) leads to the rapid formation of colorless precipitates. Si6Br12 center dot 2(p-CH3C6H4CN) adopts an "inverse sandwich" structure where the N atoms of the p-tolunitrile molecules are mu(6) bonded and are located above and below the planar hexagonal Si-6 ring.
Provided is a method for efficiently obtaining cyclohexasilane using a cyclic silane dianion salt as a raw material without a by-product such as silane gas by a simple device. The method for producing cyclohexasilane has a feature that a cyclic silane dianion salt represented by the following general formula (i) or general formula (ii) is reacted with an aluminum-based reducing agent or a boron-based reducing agent:
wherein X represents a halogen element, a represents an integer of 0 to 6, and R
1
to R
4
each independently represent a hydrogen atom, an alkyl group, or an aryl group;
wherein X represents a halogen element, a represents an integer of 0 to 6, and R
5
to R
8
each independently represent a hydrogen atom, an alkyl group, or an aryl group.