Stark Daniel G, O'Riordan Timothy J C, Smith Andrew D
EaStCHEM, School of Chemistry, University of St. Andrews , North Haugh, St. Andrews, Fife, KY16 9ST, United Kingdom.
Org Lett. 2014 Dec 19;16(24):6496-9. doi: 10.1021/ol503360q. Epub 2014 Dec 8.
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.
描述了一种异硫脲催化的迈克尔加成-内酰胺化反应,随后是硫化物氧化消除/N-到O-磺酰基转移序列,用于从(苯硫基)乙酸和α,β-不饱和酮亚胺形成2,3,5-和2,3-取代的吡啶6-甲苯磺酸盐。引入有价值的2-磺酸根基团使得能够衍生化得到一系列二取代、三取代和四取代的吡啶。