Synthesis of Di-, Tri-, and Tetrasubstituted Pyridines from (Phenylthio)carboxylic Acids and 2-[Aryl(tosylimino)methyl]acrylates
作者:Daniel G. Stark、Timothy J. C. O’Riordan、Andrew D. Smith
DOI:10.1021/ol503360q
日期:2014.12.19
An isothiourea-catalyzed Michael addition–lactamization followed by the sulfide oxidation–elimination/N- to O-sulfonyl transfer sequence for the formation of 2,3,5- and 2,3-substituted pyridine 6-tosylates from (phenylthio)acetic acids and α,β-unsaturated ketimines is described. Incorporation of the valuable 2-sulfonate group allows derivatization to a range of di-, tri-, and tetrasubstituted pyridines
异硫脲催化的迈克尔加成-内酰胺化,然后进行硫化物氧化-消除/ N-到O-磺酰基转移序列,由(苯硫基)乙酸形成2,3,5-和2,3-取代的吡啶6-甲苯磺酸酯描述了α,β-不饱和酮亚胺。有价值的2-磺酸盐基团的引入允许衍生为一定范围的二,三和四取代的吡啶。