90445-41-3Relevant academic research and scientific papers
Cobalt-catalyzed enantioselective intramolecular hydroacylation of ketones and olefins
Yang, Junfeng,Yoshikai, Naohiko
, p. 16748 - 16751 (2014)
Cobalt-chiral diphoshine catalytic systems promote intramolecular hydroacylation reactions of 2-acylbenzaldehydes and 2-alkenylbenzaldehydes to afford phthalide and indanone derivatives, respectively, in moderate to good yields with high enantioselectivities. The ketone hydroacylation did not exhibit a significant H/D kinetic isotope effect (KIE) with respect to the aldehyde C-H bond, indicating that C-H activation would not be involved in the rate-limiting step.
Photoenolisation. XI. Photooxydation des o-methylbenzophenones
Pfau, Michel,Molnar, James,Heindel, Ned D.
, p. 164 - 169 (2007/10/02)
Photoenols 2 of 2- (1a), 2,4- (1b), 2,5- (1c), 2,6- (1d), 2,2'- (1e) and 2,3'-dimethylbenzophenones (1f) were trapped by (3)O2.When a 350 nm wavelength Hg lamp (Rayonet RPR 100) was used (benzene solution) with ketones 1a-c, the corresponding 2-formyl- 4 and 2-carboxybenzophenones 8 were formed as well as 3-phenyl-phtalides 10.Compounds 4 arose from dehydration of the intermediate endoperoxydes 3.Throught photoenolisation, 2-formylbenzophenones 4 gave the intermediate ketene-enols 5 which either isomerised to phtalides 10 or added oxygen to form the corresponding endoperoxydes 6; the latter isomerised to peracids 7, which, by reaction with aldehydes 4, yielded the carboxylic acids 8.When the aerated irradiations were performed simultaneously with 350 nm light and with light above 380 nm (Hanovia 679 A-36, benzene solution), ketones 1a-f yielded the same compounds 4, 8 and 10 but also anthraquinones 13.The latter arose from reversible cyclisation of photoenols 2 E giving dihydroanthranols 11 which were trapped by oxygen, yielding the anthrones 12 which were subsequently photooxidized to anthraquinones 13.With 2,6-dimethylbenzophenone (1d), the corresponding photoenols 2 were trapped for the first time.Compounds 8d, and 13d were absent, but instead 1-carboxyanthraquinone 15 was obtained.The latter can arise from 1-methylanthraquinone 13d trough photoenolisation-oxidation process alredy reported for this compound.With 2,2'-dimethylbenzophenone 1e, 3,3'-spirobiphtalide 14 was obtained instead 2-methyl-2'-carboxybenzophenone 8e; the latter, through a photoenolisation-oxidation process analogous to that described in the second paragraph, yielded 2,2'-dicarboxybenzophenone which underwent dehydration to compound 14.Under the same conditions (Hanovia) but in acetic acid solution, anthraquinones 13 were not formed with ketones 1a-f, due to rapid reketonisation of photoenols 2 E in this medium; however, compounds 4, 8, 10 and 14 were produced.Products 8, 10, 13, 14 and 15 were isolated and characterised or identified.Yields were deduced from actual weights of the isolated compounds (carboxylic acids 8 and 15) and from GLC determinations (compounds 4, 10, 13 and 14).
