water in tetrahydrofuran byproducts: poly(diphenylsiloxane); (N2); addn. of N2 sat. H2O to soln. of Cr-compd. in warm THF; filtration (Al2O3), removal of solvent (reduced pressure), recrystn. (ligroin); detn. by (1)H- and (13)C-NMR spectroscopy;