CONTRIBUTION OF AN OXIRANE INTERMEDIATE IN THE PYROLYTIC CLEAVAGE OF THE BETA-ARYL ETHER SUBSTRUCTURE IN LIGNIN - PYROLYSIS OF 3,4-DIMETHOXYPHENYLOXIRANE

The pyrolysis of 3,4-dimethoxyphenyloxirane was studied at 500 degrees C for 4 s by Curie-point pyrolysis as a model for a potential intermediate in the pyrolysis of lignocellulosics. The primary decomposition product was 3,4-dimethoxyphenylacetaldehyde. The pyrolysis of 1-(3,4-dimethoxyphenyl)-2-(4-propylphenox)-1-ethanol, a potential precursor of 3,4-dimethoxyphenyloxirane in pyrolysis, produced 3,4-dimethoxyphenylacetaldehyde in small yields. The pyrolysis products from the model compounds suggest that oxirane intermediate formation is a minor pathway in the pyrolysis of the beta-aryl ether linkages found in lignocellulosics.