in n-heptane The soln. was refluxed for two hours under N2; separated by column chromy.. Recrystn. from hexane/diethyl ether at -80°C yielded brown crystals. Detected by IR, NMR, Elem. anal.;

in n-heptane The soln. was refluxed for two hours under N2; separated by column chromy.. Recrystn. from hexane/diethyl ether at -80°C yielded brown crystals. Detected by IR, NMR, Elem. anal.;