Synthesis of 3-Fluoropyrrolidines and 4-Fluoropyrrolidin-2-ones from Allylic Fluorides
作者:Lorraine E. Combettes、Marie Schuler、Rakesh Patel、Baltasar Bonillo、Barbara Odell、Amber L. Thompson、Tim D. W. Claridge、Véronique Gouverneur
DOI:10.1002/chem.201201576
日期:2012.10.8
were prepared by 5‐exo‐trig iodocyclisation from allylic fluorides bearing a pending nitrogen nucleophile. These bench‐stable precursors were made accessible upon electrophilic fluorination of the corresponding allylsilanes. The presence of the allylic fluorine substituent induces syn‐stereocontrol upon iodocyclisation with diastereomeric ratios ranging from 10:1 to > 20:1 for all N‐tosyl‐3‐fluoropent‐4‐en‐1‐amines
通过5 -exo-trig碘环化从带有未决氮亲核试剂的烯丙基氟化物制备了各种3-氟吡咯烷和4-氟吡咯烷酮-2-酮。这些台稳的前体在相应的烯丙基硅烷进行亲电氟化后即可获得。的存在下,烯丙基氟取代基诱导顺-stereocontrol在iodocyclisation与非对映体比率为10:1至> 20:1对所有Ñ甲苯磺酰基-3- fluoropent -4-烯-1-胺和酰胺。立体控制的意义和水平惊人地类似于带有未决氧亲核试剂的结构相关的烯丙基氟化物的相应碘环化。这些结果表明,SYN闭环时观察到的选择性涉及I 2 –π配合物,氟位于内部。