在(-)-天冬氨酸或(4S)-2,2'-存在下,使用有机锂合成6,7-环氧-8-氮杂双环[3.2.1]辛烷5的合成和对映选择性α-去质子化描述了(1-乙基亚丙基)双-4-(1-甲基乙基)-4,5-二氢恶唑,以高达85%的收率和82%的ee给出氨基环庚烯醇。研究了不同反应变量对反应曲线的影响,包括有机锂的性质,溶剂,配体,温度和环氧化物的结构。事实证明,反应取决于所有这些变量,特别是取决于底物的结构。混合有机锂系统(Pr i Li / TMSCH 2 Li)已成功用于引入潜在的通用烯丙基硅烷官能团。
Selective ring-rearrangement or ring-closing metathesis of bicyclo[3.2.1]octenes
作者:Evgeniya Semenova、Ouidad Lahtigui、Sarah K. Scott、Matthew Albritton、Khalil A. Abboud、Ion Ghiviriga、Adrian E. Roitberg、Alexander J. Grenning
DOI:10.1039/d0cc04624h
日期:——
Explored was the competitive ring-closingmetathesis vs. ring-rearrangement metathesis of bicyclo[3.2.1]octenes prepared by a simple and convergent synthesis from bicyclic alkylidenemalono-nitriles and allylic electrophiles. It was uncovered that ring-closingmetathesis occurs exclusively on the tetraene-variant, yielding unique, stereochemically and functionally rich polycyclic bridged frameworks