102599-30-4Relevant articles and documents
C-H Functionalization via Remote Hydride Elimination: Palladium Catalyzed Dehydrogenation of ortho-Acyl Phenols to Flavonoids
Zhao, Xiaomei,Zhou, Jiabin,Lin, Shuying,Jin, Xukang,Liu, Renhua
, p. 976 - 979 (2017/03/14)
Although deprotonation of electron-poor C-H bonds to carbon anions with bases has long been known and widely used in organic synthesis, the hydride elimination from electron-rich C-H bonds to carbon cations or partial carbocations for the introduction of nucleophiles is a comparatively less explored area. Here we report that the carbonyl β-C(sp3)-H bond hydrogens of ortho-acyl phenols could be substituted by intramolecular phenolic hydroxyls to form O-heterocycles, followed by dehydrogenation of the O-heterocycle into flavonoids. The cascade reaction is catalyzed by Pd/C without added oxidants and sacrificing hydrogen acceptors.
Phase-transfer catalysed alkylation of 4-hydroxycoumarin - Synthesis of α,α-disubstituted o-hydroxyacetophenones
Majumdar,Khan,Chattopadhyay
, p. 483 - 485 (2007/10/02)
Phase-transfer catalysed alkalyation of 4-hydroxycoumarin (1) with active halides give O-alkylated products, 2 (20-60%), C, O-dialkylated products, 3 (15-20%) and α,α-disubstituted-o-hydroxyacetophenones, 5 (20-75%). Only in one case C,C-dialkylated product, 4 (35%) has been obtained.
