in ethanol inert atmosphere; refluxing (2 h); filtration, cooling to -10°C (pptn.), filtration, washing (cold MeOH), recrystn. (MeOH/Et2O); elem. anal.;

CH3Li in tetrahydrofuran; diethyl ether byproducts: 1,1-bifluorenyl, LiBr; soln. of MeLi in Et2O added to soln. of fluorene in tetrahydrofuran and stirred at ambient temp. for 2 h; transfered to soln. of ((C5(CH3)5)OsBr(μ-Br))2 in tetrahydrofuran; stirred under Ar in Schlenk techniques at ambient temp. for 18 h; volatiles removed under reduced pressure; excess fluorene removed by sublimation at 50°C (0.1 Torr); residue sublimed at 110°C (0.1 Torr); elem. anal.;

in ethanol inert atmosphere; refluxing (1 h);

in tert-butyl alcohol soln. OsO4 in concd. HBr was heated to reflux for 2 h, soln. was evapd. to dryness in vacuo (< 50°C), residue was dried in vacuo at room temp. overnight, dissolved in t-BuOH under N2 atm. and treated with C5HMe5, heated to reflux for 45 min; ppt. was filtered, dried in vacuo at 110°C; elem. anal.;