86988-50-3Relevant academic research and scientific papers
Organocatalytic Aerobic Oxidation of α-Fluoroalkyl Alcohols to Fluoroalkyl Ketones at Room Temperature
Kadoh, Yoichi,Tashiro, Masayuki,Oisaki, Kounosuke,Kanai, Motomu
, p. 2193 - 2198 (2015/07/27)
The organocatalytic aerobic oxidation of electron-deficient α-fluoroalkyl alcohols at room temperature is described. The resulting fluoroalkyl ketones are versatile synthetic intermediates for a variety of fluorine-containing molecules. This otherwise difficult transformation has now been accomplished by the reaction of α-fluoroalkyl alcohols with N-oxyl radicals, catalytically generated from 9-azabicyclo[3.3.1]nonan-3-one N-oxyl/nitrogen oxide (keto-ABNO/NOx) and oxygen in acetic acid (AcOH), affording the corresponding fluoroalkyl ketones in high yield. This operationally simple reaction can be performed under mild conditions, and was applied to a wide range of alcohols (20 examples), thus demonstrating a high functional group tolerance. Moreover, a modified one-pot protocol based on this method was able to convert an aldehyde to a trifluoromethyl ketone on a gram scale.
Oxidation of α-trifluoromethyl alcohols using a recyclable oxoammonium salt
Kelly, Christopher B.,Mercadante, Michael A.,Hamlin, Trevor A.,Fletcher, Madison H.,Leadbeater, Nicholas E.
, p. 8131 - 8141 (2013/01/15)
A simple, mild method for the oxidation of α-trifluoromethyl alcohols to trifluoromethyl ketones (TFMKs) using the oxoammonium salt 4-acetylamino-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (1) is described. Under basic conditions, oxidation proceeds rapidly and affords good to excellent yields of TFMKs, without concomitant formation of the hydrate. The byproduct of the oxidation, 4-acetylamino-2,2,6,6-tetramethyl-1- piperidinyloxy (1c), is easily recovered and can be conveniently reoxidized to regenerate the oxoammonium salt.
REGIOSPECIFIC SYNTHESIS OF AROMATIC COMPOUNDS VIA ORGANOMETALLIC INTERMEDIATES. I. para-SUBSTITUTED BENZENES
Chen, Loomis S.,Chen, Grace J.,Tamborski, Christ
, p. 139 - 148 (2007/10/02)
Para-substituted benzene compounds, p-XC6H4X' (X = CF3C(O) and X' = CH3, CO2H, C(O)CF3, C(O)CH3, C(O)H and SH) have been prepared via sequential metal-halogen exchange reactions between p-BrC6H4Br and n-C4H9Li and the appropriate electrophiles.Low reaction temperature is critical to stabilization of the various intermediates.The CF3 group has a pronounced effect on providing stability to the lithium hemiketal intermediates.
4-(1-Azi-2,2,2-trifluoroethyl)benzoic Acid, a Highly Photolabile Carbene Generating Label Readily Fixable to Biochemical Agents
Nassal, Michael
, p. 1510 - 1523 (2007/10/02)
The title compound is synthesized starting from either 4-bromobenzyl tert butyldimethylsilyl ether (5b) or 4-bromobenzyl tert-butyl ether (5c) or - most simply - from 4-bromotoluene (5a).In the first step Br was replaced by Li using n-butyllithium, then the organometallic compounds were converted into the respective trifluoroacetophenones 6a - c with N-trifluoroacetylpiperidine.The azi moiety (diazirine) was prepared from the oximes 7a - c via O-tosyloximes 8a - c plus ammonia yielding the diaziridines 9a - c and oxidation of the latter with Ag2O.Oxidation by permanganate - of the ethers after acidic cleavage - yields the title compound 12.On irradation (λ > 300 nm) 12 by elimination of N2 with a half-life period of 22 s generates the corresponding carbene.At the same time from 12 with ca. 20percent the yellow isomeric 4-(1-diazo-2,2,2-trifluoroethyl)benzoic acid (20) is formed which is photolyzed generating the same carbene as 12.The synthesis of 20 is described starting from 4-bromobenzaldehyde. - The diazirine 12 as its N-hydroxysuccinimide ester 13, or using other methods of amide synthesis, can readily be coupled to amino functions of biochemically interesting agents thus forming photoaffinity labels.
