77831-70-0Relevant academic research and scientific papers
Reaction of Sulfene and Dichloroketene with Open-Chain N,N-Disubstituted α-Aminomethyleneketones. Synthesis of 4-Dialkylamino-3,4-dihydro-6-methyl-5-phenyl-1,2-oxathiin 2,2-Dioxides and of N,N-Disubstituted 4-Amino-3-chloro-(6-methyl-5-phenyl)(6-benzyl)-2H-pyran-2-ones
Bargagna, Alberto,Evangelisti, Filippo,Schenone, Pietro
, p. 111 - 116 (2007/10/02)
Cycloaddition of sulfene to N,N-disubstituted 4-amino-3-phenyl-3-buten-2-ones (III) occurred in good yield only in the case of aliphatic N-substitution to give 4-dialkylamino-3,4-dihydro-6-methyl-5-phenyl-1,2-oxathiin 2,2-dioxides, whereas N,N-disubstituted 4-amino-1-phenyl-3-buten-2-ones (IV) did not react at all.Polar 1,4-cycloaddition of dichloroketene to III and IV occurred partly in the case of aromatic N-substitution, with the exception of the morpholino derivative IVd, giving in low yield N,N-disubstituted 4-amino-3,3-dichloro-3,4-dihydro-(6-methyl-5-phenyl)(6-benzyl)-2H-pyran-2-ones, which were dehydrochlorinated with DBN to the corresponding 4-amino-3-chloro-(6-methyl-5-phenyl)(6-benzyl)-2H-pyran-2-ones (VII) in good yield.In some cases of aliphatic N,N-disubstitution of III and IV, cycloaddition led directly to N,N-dialkyl derivatives VII in low yield.
