SYNTHESIS AND SPECTROSCOPY OF HALOGENATED CYCLOPENTASILANES

Nonahalocyclopentasilanes, HSi(5)X(9), and octahalocyclopentasilanes, H(2)Si(5)X(8) (X = Cl, Br, I), were prepared by dearylation. of the co rresponding phenylated cyclosilanes HSi(5)Ph(9) and H(2)Si(5)Ph(8) wit h gaseous hydrogen halides and catalytic amounts of aluminum halides ( HX/AlX(3)) dissolved in benzene. The products were identified and char acterized by IR and NMR spectroscopy (H-1 and Si-29, including Si-H an d Si-Si coupling constants). The halogenation of trans-1,3-H(2)Si(5)Ph (8) led to isomeric mixtures of cis-1,3-H(2)Si(5)X(8) and trans-1,3-H( 2)Si(5)X(8) in equimolar amounts.