Three solvent extracted, methylated British bituminous coals were oxidized with trifluoroperoxyacetic acid (TFPA). The soluble and insoluble fractions were analysed using a range of physical and chemical techniques. The TFPA oxidized insoluble fraction from the highest rank coal, Cortonwood Silkstone, was reduced, tosylated and re-reduced. The resultant product was further solubilized by re-oxidation with TFPA. The re-oxidized insoluble residue was examined by C-13 cross-polarization/magic angle spinning n.m.r. and FT-i.r. spectroscopy.