Synthesis of Novel Fluoropicolinate Herbicides by Cascade Cyclization of Fluoroalkyl Alkynylimines
作者:Peter L. Johnson、James M. Renga、Christopher V. Galliford、Gregory T. Whiteker、Natalie C. Giampietro
DOI:10.1021/acs.orglett.5b01176
日期:2015.6.19
has been modified to allow the synthesis of 4-amino-5-fluoropicolinates. Use of N-trityl and acetal protecting groups in the cyclization precursor led to 5-fluoropyridines that were easily deprotected to picolinaldehyde derivatives for further elaboration to structures of interest as potential herbicides. This method provided access to picolinic acids with alkyl or aryl substituents at the 6-position
氟烷基炔基亚胺与伯胺的级联环化已得到修饰,可以合成4-氨基-5-氟吡啶甲酸。在环化前体中使用N-三苯甲基和乙缩醛保护基可产生5-氟吡啶,它们很容易被脱去吡啶啉醛衍生物的保护基,以进一步修饰作为潜在除草剂的目标结构。该方法提供了在6-位具有烷基或芳基取代基的吡啶甲酸的途径,这是以前无法通过交叉偶联化学获得的。