614-71-1Relevant academic research and scientific papers
A new alkylation of aryl alcohols by boron trifluoride etherate
Jumbam, Ndze Denis,Maganga, Yamkela,Masamba, Wayiza,Mbunye, Nomthandazo I.,Mgoqi, Esethu,Mtwa, Sphumusa
, (2019/10/28)
The ethylation of aryl alcohols by an ethyl moiety of boron trifluoride etherate is described. The reaction proceeded cleanly and afforded good yields of the corresponding aryl ethyl ethers. It tolerated the presence of functional groups such as aryl, alkyl, halogens, nitro, nitrile, and amino. However, the presence of amino or nitro groups ortho to a hydroxyl group of an aryl compound drastically reduced the yields of the anticipated products due to the chelation of the aforementioned functional groups with boron trifluoride etherate. A nitrogen atom in the aromatic ring system, as exemplified by hydroxypyridine and 8-hydroxyquinoline, completely inhibited the reaction. Resorcinol, hydroquinone, and aryl alcohols with aldehyde functions decomposed under the reaction conditions.
INHIBITORS OF ACETYL-COA CARBOXYLASE
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Page/Page column 53, (2010/11/17)
The present invention relates to compounds that act as acetyl-CoA carboxylase (ACC) inhibitors. The invention also relates to methods of preparing the compounds, compositions containing the compounds, and to methods of treatment using the compounds.
Streamlined synthesis of the bippyphos family of ligands and cross-coupling applications
Withbroe, Gregory J.,Singer, Robert A.,Sieser, Janice E.
, p. 480 - 489 (2013/01/03)
We describe the efficient preparation of Bippyphos, 1. The key precursor to Bippyphos, 5, was prepared via a one-pot bromination of diketone 2 followed by alkylation with pyrazole and condensation with phenylhydrazine. Lithiation of 5 and trapping with ditert-butylchlorophosphine afforded Bippyphos, 1. Using this approach we have prepared several derivatives of Bippyphos to probe the structure and activity relationships of this family of phosphine ligands. We also demonstrate the utility of these ligands in Pdcatalyzed amination reactions and other cross-coupling reactions.
Solvolysis of some arenediazonium salts in binary EtOH/H2O mixtures under acidic conditions
Pazo-Llorente, Roman,Bravo-Diaz, Carlos,Gonzalez-Romero, Elisa
, p. 3421 - 3428 (2007/10/03)
We have determined the product distribution, the rate constants for dediazoniation product formation, and the solvolytic rate constants for 2-, 3-, and 4-methylbenzenediazonium ions (2-, 3-, and 4-MBD, respectively) loss in acidic ethanol/water mixtures over the whole composition range by a combination of spectrophotometric (UV/Vis) and high performance liquid chromatography (HPLC) measurements. The observed rate constants (kobs) for substrate loss are equal to those for product formation, and they remain essentially constant (2-MBD) with changing solvent composition but increase by a factor of ≈2 (4MBD) on going from water to 100% EtOH. Up to four dediazoniation products - cresols (ArOH), chlorotoluene (ArCl), methylphenetole (ArOEt), and toluene (ArH) - were detected, depending on the solvent composition; the major dediazoniation products were the ArOH and ArOEt derivatives. The product selectivity (S) of the reaction towards nucleophiles is low and essentially constant with changing solvent composition, and good linear correlations between log kobs and Yc1 (solvent ionizing power) were observed for the three ArN2+ ions. All data are consistent with the rate-determining formation of an aryl cation, which reacts immediately with available nucleophiles. The data suggest that the distribution of neutral and anionic nucleophiles in the neighborhood of the ground state arenediazonium ion remains essentially unchanged upon dediazoniation, the observed product distribution reflecting the concentrations of nucleophiles in their immediate environment (i.e., in the first solvation shells of the arenediazonium ions). Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
Reductive free-radical alkylations and cyclisations mediated by 1-alkylcyclohexa-2,5-diene-1-carboxylic acids
Baguley, Paul A.,Walton, John C.
, p. 2073 - 2082 (2007/10/03)
A range of 1-alkylcyclohexa-2,5-diene-1-carboxylic acids were prepared by Birch reduction-alkylation of benzoic acid and their efficiency as mediators of alkyl radical chain addition and cyclisation processes was investigated. Reductive alkylations were respectably successful, even with only one or two equivalents of alkene, for secondary, tertiary and benzylic radicals. Reaction of 1-[2-(cyclohex-2-enyloxy)ethyl]cyclohexa-2,5-diene-1-carboxylic acid yielded the product of exo-trig-cyclisation, i.e. 7-oxabicyclo[4.3.0]nonane, in a yield comparable to that obtained from the tributyltin hydride induced cyclisation of 3-(2′-iodoethoxy)-cyclohexene. This, together with the isolation of both exo- and endo-cyclisation products from 1-[2-(6,6-dimethylbicyclo[3.1.1]hept-2-en-2-ylmethoxy)ethyl]cyclohexa-2,5-diene- 1-carboxylic acid established that ring closures could also be satisfactorily mediated with these reagents. Preparations were completely free of metal contaminants and direct reduction of the alkyl radicals, prior to addition or cyclisation, was completely absent. However, the desired products were accompanied by alkylbenzenes, together with by-products from the initiator decompositions, and this complicated work-up. Failure to obtain 1-[2-(prop-2-yn-1-yloxy)cyclohexyl]cyclohexa-2,5-diene-1-carboxylic acid in Birch reductive alkylations with trans-1-iodo-2-(prop-2-yn-1-yloxy)cyclohexane (and the corresponding bromide) indicated a limitation on precursor synthesis. The Birch reduction-alkylation was not of universal applicability and was suppressed for alkyl halides having β-substituents.
A New Rearrangement of Alkoxybenzyl Anions
Bates, Robert B.,Siahaan, Teruna J.,Suvannachut, Kessara
, p. 1328 - 1334 (2007/10/02)
Alkyl groups migrate from oxygen to carbon in alkyl aryl ethers which have been metalated in benzylic positions. 2,6-Dimethylanisole provides a variety of 2,6-dialkylphenols and their ethers in 45-80percent yields.Rearrangement products are obtained in 10-30percent yields from other dimethylanisoles and from methylanisoles.The reactions appear to proceed, like Wittig rearrangements, by homolytic cleavage of the alkyl-oxygen bond followed by recombination of the resulting radical pair in a different way.The rearrangements can be avoided by using methyl ethers and working at or below room temperature.
