Kettenverlängerung funktionalisierter Alkanone durch Umlagerung

摘要: Chain Expansion of Functionalized Alkanones by Rearrangement Reactions In analogy to the transamidation reactions which were published earlier a method is described prolong aliphatic C-chains two or four C-atoms. 1,3-Diketones 2-nitro alkanones are monosubstituted at C(2) condensed with e.g. methyl vinyl ketone. The reaction product transformed its chain-prolonged isomer in presence strong base via 4- 6-membered intermediate. most effective reagent for Michael 3-oxo-4-pentenoate (20). In this case it was possible convert 3-nitro-2-butanone (21) 2-acetyl-6-nitro-3-oxoheptanoate (26) 82% yield.