IR spectra were obtained on a UR-20 spectrophotometer in a thin layer. NMR spectra were recorded on a Bruker AM-300 spectrometer (IH, .300 and 13C, 75.47 MHz) in CDCI 3 using SiMe 4 as the internal standard. Commercial Me:ISil (Aldrich) wax used. 5-AUyi-5-chloro-4,4-dimethoxy
