Anti-Beckwith stereoselectivity in amidyl radical cyclisations: Bu3SnH-mediated 5-exo-trig acyl mode cyclisation of 2-substituted pent-4-enamide radicals

作者：Clark Andrew J^*; Filik Robert P; Thomas Gerard H; Sherringham John

来源：Tetrahedron Letters, 2013, 54(31): 4094-4097.

DOI：10.1016/j.tetlet.2013.05.109

• Stereochemistry
• Amidyl radical
• Cyclisation
• Pyrrolidinones
• Beckwith model

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.

• 出版日期2013-7-31