EWG assisted nucleophilic fluorination using PPHF: a strategy for the synthesis of 1,2,2-triaryl-2-fluoroethanones
作者:Anil Kumar、Anil K. Pal、Rishi D. Anand、Tej V. Singh、Paloth Venugopalan
DOI:10.1016/j.tet.2011.08.083
日期:2011.10
The nucleophilic fluorination of 1,2,2-triaryl-2-hydroxyethanones by fluoride ion has been carried out usingpyridiniumpoly(hydrogenfluoride) (PPHF) to give 1,2,2-triaryl-2-fluoroethanones in fairly good yield. The presence of electron withdrawing group (EWG), such as –COAr at the carbon bearing hydroxyl group facilitates such nucleophilic fluorination. The intermediacy of bridged oxiranyl ion and
Friedel-Crafts Arylation of α-Hydroxy Ketones: Synthesis of 1,2,2,2-Tetraarylethanones
作者:Anil Kumar、Tej V. Singh、Sajesh P. Thomas、Paloth Venugopalan
DOI:10.1002/ejoc.201403438
日期:2015.2
Friedel-Crafts arylation of a-hydroxy ketones such as 2-hydroxy- 1,2,2-triarylethanones has been achieved with a variety of arenes and heteroarenes in the presence of Lewis or Bronsted acids. Both sterically hindered and unhindered 1,2,2,2-tetrarylethanones are formed in good to excellent yields by using a stoichiometric amount of triflic acid. The intermediacy of an a-keto carbenium ion has been proposed