An efficient and practical entry to 2-amido-dienes and 3-amido-trienes from allenamides through stereoselective 1,3-hydrogen shifts

• Ryuji Hayashi,
• John B. Feltenberger,
• Andrew G. Lohse,
• Mary C. Walton and
• Richard P. Hsung

Beilstein J. Org. Chem. 2011, 7, 410–420, doi:10.3762/bjoc.7.53

• Ryuji Hayashi John B. Feltenberger Andrew G. Lohse Mary C. Walton Richard P. Hsung Department of Chemistry and Division of Pharmaceutical Sciences, University of Wisconsin, Madison, WI 53705 10.3762/bjoc.7.53 Abstract Preparations of de novo acyclic 2-amido-dienes and 3-amido-trienes through 1,3

• -configuration. In addition, 6π-electron electrocyclic ring-closure could be carried out with 3-amido-trienes to afford cyclic 2-amido-dienes, and such electrocyclic ring-closure could be rendered in tandem with the 1,3-hydrogen shift. Keywords: allenamides; 2-amido-dienes; 3-amido-trienes; electrocyclic ring

• Information File 3) of a single crystal of 2-amido-diene 10b was successfully obtained to assign unambiguously the E-configuration (Figure 1). Encouraged by this highly stereoselective isomerization, we turned our attention to the possibility of constructing synthetically much more challenging 3-amido-trienes