Synthesen von 3-Hydroxy-4-methyl-3-cyclobuten-1,2-dion (Methylmoniliformin)

Article abstract of DOI:10.1002/hlca.19800630504

New routes to 3-hydroxy-4-methyl-3-cyclobutene-1,2-dione (9), the lowest homologue of the mycotoxine moniliformin are described.A common feature of all pathways is the synthesis of methylcyclobutanes having the oxidation level 6.Precursors, which are easily transformed to 9 by acid catalyzed hydrolysis, include <2+2>-cycloadducts of in situ generated methyl ketene to tetraethoxyethylene and <2+2>-photocycloadducts of dichlorovinylenecarbonate with 1,1-dichloro-1-propene.The acid hydrolysis of <2+2>-cycloadducts of chlorotrifluoroethylene to N,N-diethyl-1-propylamine yields the diethylamine of 9 (=22) in 50percent overall yield.In addition, aconvenient one-pot-two-steps synthesis of a new electronich ethylene, 1,1,2-triethoxy-2-trimethylsilyloxy-ethylene (11), is described.