90445-38-8Relevant articles and documents
BF3-Etherate-catalyzed tandem reaction of 2-formylarylketones with electron-rich arenes/heteroarenes: An assembly of isobenzofurans
Mishra, Pawan K.,Kumar, Ankit,Verma, Akhilesh K.
supporting information, p. 6122 - 6125 (2020/06/18)
An efficient and BF3·Et2O-catalyzed chemoselective synthesis of diversified 1,3-diarylisobenzofuran in a high yield has been described. The reaction proceeds through sequential hydroarylation-cyclization between 2-formylarylketones and electron-rich arenes/heteroarenes. Advantageous features of the developed methodology include operational simplicity, a broad substrate scope, and applicability towards gram scale synthesis. The utility of isobenzofuran derivatives as the diene was extended to the synthesis of [4+2] cyclo-adducts with DMAD and the synthesis of 1,2-dicarbonylarenes in good yields.
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).
