in neat (no solvent) (N2) or vacuum, heated at 100°C for 5 min,; HN(SiMe3)2 removed under reduced pressure, extracted with hexane, filtered, volume reduced under reduced pressure, cooled overnight to -20°C, elem. anal.;

in neat (no solvent) inert atmosphere; 90°C, 1 h; evapn. of HN(SiMe3)2 (reduced pressure), extn. (hexane), filtration, partial evapn. (reduced pressure), crystn. (-20°C, overnight); elem. anal.;

in neat (no solvent) (N2) or vacuum, heated at 100°C for 5 min,; volatile material removed under reduced pressure, extracted with hexane, filtered, volume reduced under reduced pressure, slow cooled to -20°C, elem. anal.;

in neat (no solvent) inert atmosphere; 90°C, 1 h; evapn. of volatiles (reduced pressure), extn. (hexane), filtration, partial evapn., crystn.;