177420-63-2Relevant articles and documents
Halogen-metal exchange of 3-substituted 1,2-dibromoarenes: The use of long-range JCH coupling constants to determine regiochemistry
DiMichele, Lisa,Menzel, Karsten,Mills, Paul,Frantz, Doug,Nelson, Todd
, p. 1041 - 1043 (2006)
Regioselective halogen/metal exchange reactions were carried out on a series of 3-substituted-1,2-dibromoarenes. Product mixtures were quenched with CO2 to form the corresponding benzoic acid analogs to facilitate HPLC and NMR analysis. Substitution at the 3-position could readily be assigned on the basis of 2D HMBC long-range correlations, while assignment at the 2-position was not as straightforward. The use of three-bond JCH coupling constant measurements, extracted from 1-D 1H coupled 13C experiments, were necessary to render unequivocal regio assignments. Copyright
INHIBITORS OF STEAROYL-COA DESATURASE
-
, (2009/06/27)
Provided herein are compounds of the formula (I): as well as pharmaceutically acceptable salts thereof, wherein the substituents are as those disclosed in the specification. These compounds, and the pharmaceutical compositions containing them, are useful for the treatment of diseases such as, for example, obesity.
Reagent-modulated optional site selectivities: The metalation of o-, m- and p-halobenzotrifluorides
Mongin,Desponds,Schlosser
, p. 2767 - 2770 (2007/10/03)
Chloro(trifluoromethyl)benzenes and bromo(trifluoromethyl)benzenes undergo deprotonation at a position adjacent to the single halogen substituent when treated with alkyllithiums (at -75°C) and, respectively, lithium 2,2,6,6-tetramethylpiperidide (at -100°C) in tetrahydrofuran. Positional ambiguities, if existing, can be exploited to establish optional site selectivities. Thus, butyllithium reacts with 1-chloro-3-(trifluoromethyl)benzene under hydrogen/metal interconversion at the 2-position whereas sec-butyllithium attacks exclusively the 6-position. The latter mode of regioselectivity is also exhibited by 1-bromo-3-(trifluoromethyl)benzene in the presence of lithium 2,2,6,6-tetramethylpiperidide, only 2-bromo-4-(trifluoromethyl)phenyllithium being produced. 2-Bromo-6-(trifluoromethyl)phenyllithium is directly inaccessible, but is formed when 2-bromo-3-(trifluoromethyl)phenyllithium, generated at -100°C, is allowed to isomerize at -75°C.