141192-61-2Relevant articles and documents
Anti-Beckwith stereoselectivity in amidyl radical cyclisations: Bu 3SnH-mediated 5-exo-trig acyl mode cyclisation of 2-substituted pent-4-enamide radicals
Clark, Andrew J.,Filik, Robert P.,Thomas, Gerard H.,Sherringham, John
, p. 4094 - 4097 (2013/07/26)
2-Substituted amidyl radicals derived from 8a-d and 9a-d undergo acyl mode 5-exo-trig cyclisation to give 3,5-trans pyrrolidinones 11a-d and 14a-d as the major products in low diastereoselectivity (de = 9-36%). The steric nature of the nitrogen substituent attached to the amidyl radical does not have a significant effect on selectivity. The stereochemical outcome is opposite to that expected based upon applying the Beckwith rule.
Amino-Claisen rearrangements and Diels-Alder reactions of ketene N,O-acetals: Reactivity studies. On the way to a novel tandem process?
Neuschuetz, Klaus,Simone, Jean-Mary,Thyrann, Thomas,Neier, Reinhard
, p. 2712 - 2737 (2007/10/03)
We report the synthesis of N-benzyl-N-[(E)-buta-1,3-dienyl]propanamide (6) and its corresponding O-silyl-substituted ketene N,O-acetal 7 and their Diels-Alder reaction. Propanamide 6 reacted smoothly, whereas the yield obtained from 7 was low, probably due to polymerization of the dienophile induced by electron transfer. The ketene N,O-acetals 27a-g were synthesized starting from the corresponding benzamides 25a-e (Scheme g). The ketene N,O-acetals 27a-g showed increased stabilities and underwent amino-Claisen rearrangements under thermal conditions. Using catalysts, interesting side reactions leading either to the annulated systems rac-35-37 or to a β-lactam rac-34 were observed.
