13659-24-0Relevant 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.
The Catalyst-Controlled Regiodivergent Chlorination of Phenols
Maddox, Sean M.,Dinh, Andrew N.,Armenta, Felipe,Um, Joann,Gustafson, Jeffrey L.
supporting information, p. 5476 - 5479 (2016/11/17)
Different catalysts are demonstrated to overcome or augment a substrate's innate regioselectivity. Nagasawa's bis-thiourea catalyst was found to overcome the innate para-selectivity of electrophilic phenol chlorination, yielding ortho-chlorinated phenols that are not readily obtainable via canonical electrophilic chlorinations. Conversely, a phosphine sulfide derived from 2,2′-Bis(diphenylphosphino)-1,1′-binaphthyl (BINAP) was found to enhance the innate para-preference of phenol chlorination.
Copper(I)-Induced Bromo-Hydrogen Exchange of 2,3-Dibromoanilines
Liedholm, Brita
, p. 877 - 884 (2007/10/02)
The copper(I)-induced bromine-hydrogen exchange reaction of 2,3-dibromoaniline and 5-substituted 2,3-dibromoanilines in the 2-position has been kinetically studied in water-acetic acid-hydrochloric acid medium at 90 deg C.The dehalogenation reaction is of second order, first order in both substrate and Cu+, and may be interpreted as a reductive substitution, composed of two one-electron steps.The 2,3-dibromophenol was only qualitatively investigated, but gave similar results.