All melting points were uncorrected. IR spectra were recorded on a Perkin-Elmer 257 grating spectrometer as potassium bromide disks (KBr). and 13C NMR spectrawere recorded on a Varían XL-100 spectrometer. Mass spectra were obtained with a Varían MAT CH-7 spectrometer. The samples were prepared for NMR analysis by using CDC13 with Me4Si as internal standard. © 1980, American Chemical Society. All rights reserved.