in further solvent(s) Kinetics; byproducts: (13)CH4, benzene, phenol; under Ar; C6H5O(13)CH3 heated in supercritical toluene-d5 (400-600°C) in the dark; cooled to room temp.; monitored by (1)H and (13)C NMR spectra; (13)CH4, methane, benzene, phenol, bibenzyl, formaldehyde obtained;