Rearrangements of Cyclobutenones. Synthesis of N-Methyl-7,8-dihydrobenzophenanthridine-9,12-diols and Related Compounds
摘要:
A useful synthetic route to benzophenanthridines and annulated derivatives is reported. These arise from the thermolysis (refluxing chlorobenzene) of squaric acid-derived C(3-N-methyl-N-arylpropynyl)-cyclobutenones via a mechanism which involves an electrocyclic ring opening of the cyclobutenone to the corresponding enynylketenes. Subsequent ring closure to a diradical intermediate followed by radical arylation gives the benzophenanthridines.
Rearrangements of Cyclobutenones. Synthesis of N-Methyl-7,8-dihydrobenzophenanthridine-9,12-diols and Related Compounds
摘要:
A useful synthetic route to benzophenanthridines and annulated derivatives is reported. These arise from the thermolysis (refluxing chlorobenzene) of squaric acid-derived C(3-N-methyl-N-arylpropynyl)-cyclobutenones via a mechanism which involves an electrocyclic ring opening of the cyclobutenone to the corresponding enynylketenes. Subsequent ring closure to a diradical intermediate followed by radical arylation gives the benzophenanthridines.