Oximes trifluoromethyl

Furan-2-carbaldehyde, 5-trifluoromethyl- H NMR, 4, 558 (68JHC95) Furan-2-carbaldehyde oxime, 5-nitro-X-ray, 4, 537 (72JCS(P2)I033) Furan-3-carbaldehyde... 

Trifluoromethyl-l-oxa-2-aza-l,3-butadienes can be prepared in situ by 1,4-HBr elimination from the corresponding a-bromo oxime on treatment with base, and provide an interesting and versatile four-skeleton-atom building block [262] (equation 57). 

Secondary aziridines bearing a trifluoromethyl group were prepared via the Hoch-Campbell reaction of Grignard reagents and oximes bearing a trifluoromethyl... 

CN ( )-5-methoxy-1 -[4-(trifluoromethyl)phenyl]-1 -pentanone 0-(2-aminoethyl)oxime hydrogen maleate... 

C21H22F3N3OS 807-57-8) see Fluphenazine Y-[4-(trifluoromethyl)phenoxyJbenzenepropanamine -(Ci HiftFjNO 83891-03-6) see Fluoxetine (3-trifluoromethylphenyl)acetone (CioHgFjO 21906-39-8) see Fenfluramine (3-trifluoromethylphenyl)acetone oxime (CiijHkjFjNO, 834-19-5) see Fenfluramine [[[2-(trifiuoromethyl)phenyl]amino]methylene]propane-dioic acid diethyl ester (C 3Hi(,F3N04 23779-94-4) see Floctafenine... 

R2=MeC>2C, R3 = d-F CC F ), regioisomeric 4-trifluoromethyl-5-isoxazole-carboxylates, 213 (R1 =Me02C, R2 =CF3, R3 = 4-F3CC6H4) and unexpectedly oximinoyl chloride 214, resulted by 1,4-addition. Product distribution is rationalized in terms of two competing reactions, either 1,4-addition of the oximate anion to the acetylenic ester or formation of the nitrile oxide followed by 1,3-dipolar cycloaddition. Anionic 1,4-addition of the oximinoyl chloride to the acetylenic ester is favoured at low temperatures, while nitrile oxide formation, followed by cycloaddition, occur at temperatures above 0 ° (371). 

Nitroso compounds (e.g. 116, equation 85) that are unable to tautomerize to oximes undergo an ene reaction with aikenes 117 giving Af-aUylhydroxylamines 118 (equation 85). Both trifluoromethyl and aryl nitroso compounds react with aikenes although in many cases the resulting Af-allylhydroxylamines are prone to subsequent chemical transformations. If allylzinc compounds are used as the aikene components, the chemos-electivity of the reaction is reversed and O-allylation products are preferably formed . 

Recent advances in radical reactions have greatly benefited from the efficiency of organotin reagents as mediators. Radical reaction of alkyl iodides with trifluoromethyl phenylsulfonyl oxime ether 69 and hexamethylditin at 300 nm in benzene afforded the corresponding trifluoromethyl oxime ethers 70 in high yields (Scheme 37) . 

The reactions of l-aryl-2,2,2-trifluoroethanone oximes 378 with tetrasulfur tetranitride (S4N4) in toluene at reflux gave 5-aryl-5-trifluoromethyl-4//-l,3,2,4,6-dithiatriazines 379, l-aryl-2,2,2-trifluoroethylideneaminosulfenamides 380 and sulfur (equation 165) . ... 

There are more than 100 patents for plant protection by 1,2,4-oxadiazoles. For instance, the oxime ether (257) is claimed to be more effective than known compounds against Phytophthora infestans when applied protectively to tomatoes <87GEP(0)3528753>. Sprays of 5-trifluoromethyl-1,2,4-oxadiazoles, such as (258), show 90-100% protection against Erysiphe gmminis in barley <89JAP(K)63162680>. Other oxadiazoles, for example (259), show complete control of diverse weeds with no damage to rice crops <91JAP(K)02250873>. 

Trifluoromethyl substituted 1 -oxadiazoles 113 were prepared by heating the bis(oximes) 112 with dry silica <99H(51)627>. l -Oxadiazole-2-oxides(furoxans)are often produced by dimerisation of nitrile oxides and some novel examples of the method, which produces 3,4-disubstituted derivatives bearing medium and large rings, have been described <99JOC8428>. Two examples of compounds prepared in this way from bis(nitrile oxides) are the ftiroxans 114 (84%) and 115 (86%). 

A range of 2,2-bis(trifluoromethyl)-l,3-oxazepin-5-ones (334) has been prepared by the reaction of oxazolidin-5-ones with 1-diethylamino-l-propyne (75TL3223). l,3-Oxazepan-2-one has been prepared by the Beckmann rearrangement of tetrahydro-2-pyranone oxime. 

H2N N J o N xf3 fluvoxamine 5-Methoxy-1-(4-trifluoromethyl-phenyl)-pentan-1-one 0-(2-amino-ethyl)-oxime, Ci5H21F3N202, MW 318.34, [54739-18-3] headache, migraine (50-100 mg/day for 8-12 weeks) Manna et al., 1994... 

Dehydrofluorination of lV,0-bis(trifluoromethyl)hydroxylamine (14) with potassium fluoride gives, in excellent yield, the perfluorinated oxime ether 15 with aC = N bond.109... 

Bis(trifluoromethyl)oximes also are highly reactive dipolarophiles, as evidenced by the facile regiospecific addition of diazomethane [32] (equation 28)... 

Trifluoromethyl Imines, Oximes, Hydrazones, Imidoyl Chlorides, Nitrones, Diazo and Diazirine Compounds... 

The synthetic scheme often applied for the preparation of 3-aryl-3-(trifluoromethyl)-3//-diazirine nowadays is shown in Scheme 5a [60]. It starts by lithiation of an aryl bromide (38), which subsequently reacts with /V-ftrifluoroacetyl)piperidine 39 (easily prepared from trifluoroacetic anhydride and piperidine) under the formation of trifluoroacetophenone 40. Next, the ketone is converted into the corresponding oxime 41, after which the hydroxyl group is converted into its tosylate (42). Reaction with liquid ammonia (usually under pressure) allows the installment of the diaziridine group (43). Subsequent oxidation with iodine finally results in the diazirine (44). This five-step reaction sequence is especially compatible with acid-labile protective groups, which are often used to protect and/or install functionalities at the R position. 

Another interesting process was found (94IZV1068, 94IZV1073, 94IZV1449). Investigation of the reaction of perfhioro-2-methylpent-2-ene with acetone oxime showed that the acetone oxime ether 3-perfluoro-2-methylpent-2-en-2-yl 83 formed initially reacts at 100 °C for 1 h, giving 4-hydroxy-3-methyl-5,5-bis(trifluoromethyl)-4-pentafluoroethylpyrrolone-l 84 in quantitative yield the structure of this product was confirmed by X-ray analysis. 

Some examples of the preparation of oxirancs, thiiranes and aziridines by the reaction of diazo compounds with trifluoromethyl-substituted carbonyl and thiocarbonyl compounds. imines,and oximes arc known. However, as noted in Section 2.1.1.6.2.5.1., carbenes are not always the reactive species. Thus, the reaction can consist of a 1,3-dipolar cycloaddition, followed by decomposition of the resulting pyrazolinc. 

The solubility of the catalyst salt is improved by the use of 3,5-bis(trifluoromethyl)phenylborate or triflate anions. Unsaturated fatty acids can be reduced in the same way.173 Hydrogenations in sc carbon dioxide can be more selective than in the gas phase while using 35 times less catalyst.174 Cyclohexene was reduced with hydrogen and a polysilox-ane-supported palladium catalyst in in a continuous-flow reactor in 95-98% yields. Epoxides, oximes, nitriles, aldehydes, ketones, and nitro compounds can also be reduced. By varying the temperature, the products from the reduction of nitrobenzene can be selected from aniline, cyclo-hexylamine, dicyclohexylamine, and cyclohexane. In the... 

Fluvoxamine, 5-Methoxy-I-(4-(trifluoromethyl )-phenylj-l-pentanone 0-(2-atninoeihyt)oxime 5-methoxy-4 -(trlfluoromethyl)valerophenone ( ) -0-(2 -aminoethyl) -oxime. CjsHjjFjNjOj mol wt 318-35. C 56.59%, H 6.65%,... 

Fluorination. In a freon solvent, this powerful fluorinating agent is able to convert compounds containing C=N (ketone oxime ethers, hydrazones) and C=S groups to gew-difluorides. Trifluoromethyl derivatives are directly obtained from alkyl dithioates. Caution must be paid to avoid the use of oxygenated solvents with which BrFi reacts violently. 

Structurally similar compound 99 with trifluoromethyl group in isoxazole ring is prepared by the intramolecular cyclization of alkynyl oxime 98 (Scheme 12.14). °... 

In the case of 9, the approach involved reaction of a trifluoroalkane-2,3-dione-3-oxime with cyclohexanone, while synthesis of 41 was achieved via ring expansion of A -methyloxadiazolium salts. The scope and limitations of the 2,3-dione-3-oxime route to 9 is difficult to evaluate since only a single example was reported, though a trifluoromethyl group may be required for activation of this system and thus would limit possible substitution patterns on the resulting oxadiazine ring. However, the reaction would presumably tolerate a number of different ketone partners, thereby increasing its scope. 

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