An unusual boron tribromide-mediated, one-pot bromination/cyclization reaction. Application to the synthesis of a highly strained cyclopenta[1,3]cyclopropa[1,2-b]pyrrolizin-8-one

作者：Jourdan Jean Pierre; Rochais Christophe; Legay Remi; Santos Jana Sopkova de Oliveira; Dallemagne Patrick^*

来源：Tetrahedron Letters, 2013, 54(9): 1133-1136.

DOI：10.1016/j.tetlet.2012.12.056

• Tripentone
• Jefford's reaction
• Cyclopentacyclopropapyrrolizinone
• Pyrrolohydrindolone

Performing Jefford's cyclization of ethyl 2-pyrrol-1-ylcyclohex-2-ene-1-carboxylate (5) using boron tribromide in refluxing dichloromethane led to a trans-cis bromopyrrolohydrindolone 7 whose debromination in alkaline medium afforded a highly strained cyclopenta[1,3]cyclopropa[1,2-b]pyrrolizin-8-one 6. Compound 7 and two of its diastereoisomers were synthesized in order to better understand this unusual reaction and more generally the reactivity of these systems.

• 出版日期2013-2-27