89-68-9Relevant articles and documents
Catalyst-Controlled Regioselective Chlorination of Phenols and Anilines through a Lewis Basic Selenoether Catalyst
Dinh, Andrew N.,Maddox, Sean M.,Vaidya, Sagar D.,Saputra, Mirza A.,Nalbandian, Christopher J.,Gustafson, Jeffrey L.
, p. 13895 - 13905 (2020/11/03)
We report a highly efficient ortho-selective electrophilic chlorination of phenols utilizing a Lewis basic selenoether catalyst. The selenoether catalyst resulted in comparable selectivities to our previously reported bis-thiourea ortho-selective catalyst, with a catalyst loading as low as 1%. The new catalytic system also allowed us to extend this chemistry to obtain excellent ortho-selectivities for unprotected anilines. The selectivities of this reaction are up to >20:1 ortho/para, while the innate selectivities for phenols and anilines are approximately 1:4 ortho/para. A series of preliminary studies revealed that the substrates require a hydrogen-bonding moiety for selectivity.
Semisynthetic Phenol Derivatives Obtained from Natural Phenols: Antimicrobial Activity and Molecular Properties
Pinheiro, Patrícia Fontes,Menini, Luciana Alves Parreira,Bernardes, Patrícia Campos,Saraiva, Sérgio Henriques,Carneiro, José Walkimar Mesquita,Costa, Adilson Vidal,Arruda, Társila Rodrigues,Lage, Mateus Ribeiro,Gon?alves, Patrícia Martins,Bernardes, Carolina De Oliveira,Alvarenga, Elson Santiago,Menini, Luciano
, p. 323 - 330 (2018/01/17)
Semisynthetic phenol derivatives were obtained from the natural phenols: thymol, carvacrol, eugenol, and guaiacol through catalytic oxychlorination, Williamson synthesis, and aromatic Claisen rearrangement. The compounds characterization was carried out by 1H NMR, 13C NMR, and mass spectrometry. The natural phenols and their semisynthetic derivatives were tested for their antimicrobial activity against the bacteria: Staphylococcus aureus, Escherichia coli, Listeria innocua, Pseudomonas aeruginosa, Salmonella enterica Typhimurium, Salmonella enterica ssp. enterica, and Bacillus cereus. Minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were determined using concentrations from 220 to 3.44 μg mL-1. Most of the tested compounds presented MIC values ≤220 μg mL-1 for all the bacteria used in the assays. The molecular properties of the compounds were computed with the PM6 method. Through principle components analysis, the natural phenols and their semisynthetic derivatives with higher antimicrobial potential were grouped.
Enzymatic halogenation of the phenolic monoterpenes thymol and carvacrol with chloroperoxidase
Getrey, Laura,Krieg, Thomas,Hollmann, Frank,Schrader, Jens,Holtmann, Dirk
, p. 1104 - 1108 (2014/03/21)
The conversion of the phenolic monoterpenes thymol and carvacrol into antimicrobials by (electro)-chemoenzymatic halogenation was investigated using a chloroperoxidase (CPO) catalyzed process. The CPO catalysed process enables for the first time the biotechnological production of chlorothymol, chlorocarvacrol and bromothymol as well as a dichlorothymol with high conversion rates, total turnover numbers and space time yields of up to 90%, 164000 and 4.6 mM h -1, respectively.