3098-18-8Relevant articles and documents
Aerobic Copper-Catalyzed Salicylaldehydic Cformyl?H Arylations with Arylboronic Acids
Xiao, Lin,Lang, Tao-Tao,Jiang, Ying,Zang, Zhong-Lin,Zhou, Cheng-He,Cai, Gui-Xin
supporting information, p. 3278 - 3283 (2021/02/01)
We report a challenging copper-catalyzed Cformyl?H arylation of salicylaldehydes with arylboronic acids that involves unique salicylaldehydic copper species that differ from reported salicylaldehydic rhodacycles and palladacycles. This protocol has high chemoselectivity for the Cformyl?H bond compared to the phenolic O?H bond involving copper catalysis under high reaction temperatures. This approach is compatible with a wide range of salicylaldehyde and arylboronic acid substrates, including estrone and carbazole derivatives, which leads to the corresponding arylation products. Mechanistic studies show that the 2-hydroxy group of the salicylaldehyde substrate triggers the formation of salicylaldehydic copper complexes through a CuI/CuII/CuIII catalytic cycle.
Series of high spin mononuclear iron(III) complexes with Schiff base ligands derived from 2-hydroxybenzophenones
Pogány, Luká?,Moncol, Ján,Pavlik, Ján,?alitro?, Ivan
supporting information, p. 5904 - 5915 (2017/07/10)
The reaction of various phenols with benzoyl chloride afforded the derivatives of phenyl benzoate that subsequently underwent Fries rearrangement. The obtained 2-hydroxybenzophenone analogues were combined with linear aliphatic triamines, which afforded pentadentate Schiff base ligands. Moreover, nine new iron(iii) complexes with the general formula [Fe(Ln)X] (where, Ln is the dianion of the pentadentate Schiff base ligand, N,N′-bis((2-hydroxy-5-methylphenyl)phenyl)methylidene-1,5-diamino-3-azapentane = H2L1, N,N′-bis((2-hydroxy-3,5-dimethylphenyl)phenyl)methylidene-1,5-diamino-3-azapentane = H2L2, N,N′-bis((2-hydroxy-5-chlorophenyl)phenyl)methylidene-1,5-diamino-3-azapentane = H2L3, N,N′-bis((2-hydroxy-4-methylphenyl)phenyl)methylidene-1,5-diamino-3-azapentane = H2L4, N,N′-bis((2-hydroxy-5-bromophenyl)phenyl)methylidene-1,7-diamino-4-azaheptane = H2L5, N,N′-bis((2-hydroxy-5-bromophenyl)phenyl)methylidene-1,7-diamino-4-methyl-4-azaheptane = H2L6 and X is the chlorido, azido or isocyanato terminal ligand) were synthesized and characterized via elemental analysis, and IR and UV-VIS spectroscopy; in addition, the crystal structures of all the complexes were determined by X-ray diffraction. Magnetic investigation reveals high spin state behaviour in all the reported compounds. DFT calculations and analysis of the magnetic functions allowed to extract absolute values of the zero field splitting parameters and exchange coupling constants.
Comparisons of O-acylation and Friedel-Crafts acylation of phenols and acyl chlorides and Fries rearrangement of phenyl esters in trifluoromethanesulfonic acid: Effective synthesis of optically active homotyrosines
Murashige, Ryo,Hayashi, Yuka,Ohmori, Syo,Torii, Ayuko,Aizu, Yoko,Muto, Yasuyuki,Murai, Yuta,Oda, Yuji,Hashimoto, Makoto
experimental part, p. 641 - 649 (2011/03/19)
Reactions involving phenol derivatives and acyl chlorides have to be controlled for competitive O-acylations and C-acylations (Friedel-Crafts acylations and Fries rearrangements) in acidic condition. The extent for these reactions in trifluoromethanesulfonic acid (TfOH), which is used as catalyst and solvent, is examined. Although diluted TfOH was needed for effective O-acylation, concentrated TfOH was required for effective C-acylations in mild condition. These results have been applied to the novel synthesis of homotyrosine derivatives. Both Fries rearrangement of N-TFA-Asp(OBn)-OMe and Friedel-Crafts acylation of phenol with N-TFA-Asp(Cl)-OMe in TfOH afforded the homotyrosine skeleton, followed by reduction and deprotection afforded homotyrosines maintaining stereochemistry of Asp as an optically pure form.
