potassium dichromate in acetic acid

in dichloromethane byproducts: (C6H5)3SiOSi(C6H5)3; React. of CrO3 with Ph3SiCl in CH2Cl2 results in an orange-red soln. after stirring of mixt. (24 h, room temp., vac. or Ar).; Filtn., evapn., removal of CrO2Cl2, extn. (hot hexane), combining of filtered ext., refiltn. and cooling to 0°C yields CrO2(OSiPh3)2 as yellow-orange needles, which are filtered and cooled at -20°C to afford CrO2Cl(OSiPh3). Elem. anal.;

in dichloromethane byproducts: HCl; React. of CrO2Cl2 with 1 equiv of Ph3SiOH in CH2Cl2 results in an orange-red soln. after stirring of mixt. (24 h, room temp., vac. or Ar).; Filtn., evapn., removal of CrO2Cl2, extn. (hot hexane), combining of filtered ext., refiltn. and cooling to 0°C yields CrO2(OSiPh3)2 as yellow-orange needles, which are filtered and cooled at -20°C to afford CrO2Cl(OSiPh3). Elem. anal.;