Neighboring Group Participation in the Additions of Iodonium and Bromonium Ions to <i>N</i>-Alkoxycarbonyl-2-azabicyclo[2.2.<i>n</i>]alk-5-enes (<i>n</i> = 1,2)
作者:Grant R. Krow、Deepa Gandla、Weiwei Guo、Ryan A. Centafont、Guoliang Lin、Charles DeBrosse、Philip E. Sonnet、Charles W. Ross、Harri G. Ramjit、Patrick J. Carroll、Kevin C. Cannon
DOI:10.1021/jo702153q
日期:2008.3.1
Additions of iodonium-X reagents to N-alkoxycarbonyl-2-azabicyclo[2.2.1]hept-5-enes and the homologous 2-azabicyclo[2.2.2]oct-5-enes have been found to mirror the outcomes of additions of bromonium-X reagents. Only rearranged products were observed for reactions of either of these halonium ion reagents with the azabicylo[2.2.1]hept-5-enes. For the azabicyclo[2.2.2]oct-5-enes, nitrogen participation in
已发现将碘鎓-X试剂添加到N-烷氧基羰基-2-氮杂双环[2.2.1]庚-5-烯和同源的2-氮杂双环[2.2.2]辛-5-烯中可以反映出添加碘的结果。溴X试剂。仅观察到重排产物,这些ha离子试剂中的任何一种都与氮杂双[2.2.1]庚-5-烯反应。对于氮杂双环[2.2.2]辛-5-烯,除了IOH或BrOH外,氮的参与还取决于N-烷氧基羰基。通过较大的N -Boc,N -Cbz或N -Troc保护基,C处的亲核攻击形成未重排的5-抗-羟基-6- syn -I(或Br)-2-氮杂双环[2.2.2]辛烷5在合成hal离子上 X射线分析重新确定了N-甲基-8-抗溴4-抗羟基-2-氮杂双环[3.2.1]辛烷的结构。
Selectfluor as a Nucleofuge in the Reactions of Azabicyclo[<i>n</i>.2.1]alkane β-Halocarbamic Acid Esters (<i>n</i> = 2,3)
作者:Grant R. Krow、Deepa Gandla、Weiwei Guo、Ryan A. Centafont、Guoliang Lin、Charles DeBrosse、Philip E. Sonnet、Charles W. Ross、Harri G. Ramjit、Kevin C. Cannon
DOI:10.1021/jo702155v
日期:2008.3.1
4-anti-Y-8-anti-X-6-azabicyclo[3.2.1]octanes. The azabicycles contained X = I or Br groups in the methano bridge and Y = F, Br, Cl, or OH substituents in the larger bridge. The relative reactivities of the halides were a function of the azabicycle, the halide, and its bridge and the addition of Selectfluor or HgF2 as a nucleofuge. All halide displacements occurred with retention of stereochemistry. Selectfluor with