105538-90-7Relevant academic research and scientific papers
Photochemical Rearrangement of α-Chloro-Propiophenones to α-Arylpropanoic Acids: Studies on Chirality Transfer and Synthesis of (S)-(+)-Ibuprofen and (S)-(+)-Ketoprofen
Sonawane, Harikisan,Bellur, Nanjundiah S.,Kulkarni, Dilip G.,Ayyangar, Nagaraj R.
, p. 1243 - 1260 (1994)
A new single-step efficient photochemical approach for α-arylpropanoic acids (4) from α-chloro-propiophenones (5) is described.It involves carbonyl triplet excited state directed 1,2-aryl migration of the aryl group which has been found to be highly dependent upon the nature of the aryl substituent.The mode of the rearrangement is probed by the study of the photobehaviour of a set of optically active α-chloro-propiophenones.The results suggest that the nature of the carbonyl triplets (n, ?*/ ?, ?*) plays an important role in the chirality transfer.This method finds application in the synthesis of optically active ibuprofen (4e) and ketoprofen (26), though in moderate optical yields.
Zinc Salt Catalyzed Rearrangement of Acetals of Optically Active Aryl 1-Chloroethyl Ketones: Synthesis of Optically Active 2-Arylpropionic Acids and Esters
Piccolo, Oreste,Spreafico, Franca,Visentin, Giuseppina,Valoti, Ermanno
, p. 10 - 14 (2007/10/02)
The preparation of (S)-2-(4'-isobutylphenyl)propionic acid ((S)-Ibuprofen) (82percent optical purity) and (S)-2-(6'-methoxy-2'-naphthyl)propionic acid (Naproxen) (96percent optical purity) has been accomplished by starting from optically pure (S)-2-chloropropionyl chloride.The investigation for finding the best experimental conditions and minimizing racemization phenomena is presented.
