Reduction of Organosilicon Peroxides: Ring Contraction and Cyclodimerization

The reduction of 1,2,7,8-tetraoxa-3,6-disilonanes is accompanied by the selective transformation of two SiOOC moieties into SiOC moieties, resulting in contraction of the nine-membered ring bis-peroxide to a previously unknown class of seven-membered-ring acetals, 1,6-dioxa-2,5-disilepanes. The reduction of six-membered cyclic peroxide proceeds differently and affords four- and eight-membered rings. As a result, silyl ethers of gem-diols, which do not exist in the free form, are produced.