bis-triphenylphosphine-palladium(II) chloride; 3,3',5,5'-tetra-tert-butyl-2,2'-di-hydroxy-1,1'-biphenyl; 9,9-dimethyl-4,5-bis(diphenyl-phosphino)xanthene in neat (no solvent) T=132°C; 3 h; Inert atmosphere;