Tetrasilabutadiene cycloaddition reaction

The treatment of hexakis(2,4,6-triisopropylphenyl)tetrasilabutadiene with maleic anhydride furnished the 2,9-dioxa-5,6,7,8-tetrasilatetracyclodecan-3-one derivative 29 (Scheme 19). The reaction pathway involves a [2+2] cycloaddition of one of the Si=Si bonds of tetrasilabutadiene to the highly reactive C=0 group, followed by a second cycloaddition of the remaining Si=Si bond across the C=C double bond to complete the formation of the final product 29 <20010M2451>. 

Addition Reactions. While cycloadditions to 6 are still exceedingly rare, reactions of 6 with small molecules, as summarized in Scheme 8.1, were more successful. Treatment of the tetrasilabutadiene with small amounts of water led, via the 1,2-addition product 16 to the rearranged oxatetrasilacyclopentane 17, an analogue of tetrahydrofuran. With an excess of water the tetrasilane-l,4-diol 18 was obtained, which showed no tendency to eliminate water with the formation of 17. ... 

Keywords silylenes, disilenes, tetrasilabutadiene, multiple bonds, addition reactions, cycloadditions, germanium compounds... 

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