Furyl ketone

Chemically, wood tar is a complex mixture that contains at least 200 individual compounds, among which the foUowing have been isolated (1) 2-methoxyphenol, 2-methoxy-4-ethylphenol, 5-meth5i-2-methoxyphenol, 2,6-x5ienol, butyric acid, crotonic acid, 1-hydroxy-2-propanone, butyrolactone, 2-methyl-3-hydroxy-4JT-pyran-4-one, 2-methyl-2-propenal, methyl ethyl ketone, methyl isopropyl ketone, methyl furyl ketone, and 2-hydroxy-3-methyl-2-cyclopenten-l-one. 

Studies of cathodic reduction have been few. Amusingly, attempted anodic oxidation of the furyl ketone 123 actually resulted in cathodic reduction to the dimer 124 the corresponding ester was oxidized normally, however.301 Sometimes the dimethoxydihydrofurans formed in oxidation processes are reduced in a side reaction leading to the tetrahydrofuran derivatives.302 By using dimethylformamide as solvent instead of the protic solvents used formerly, a Czech group has demonstrated that the cathodic reductions of furans can produce fairly stable anion radicals having ESR spectra which agree well with theory.3023... 

Monomers 1 (22), 2 (23) and 6 do not polymerize with anionic initiators or give low yields of ill-defined oligomers. Vinyl 2-furyl ketone 5 (24) is sensitive to anionic activation, but the products have low molecular weights. The most interesting results have been obtained with 3 and 4. 

The series of new 4-aryl-2-phenylthieno[3,4- ]furans 396 and the selenium analogue 397 were prepared from the readily available aryl 2-bromomethyl-5-phenyl-3-furyl ketones by cyclization with thioacetamide and iV,iV-diethyl-selenopropanamide, respectively (Equation 9) <1998JHC71>. 

When Grignard reagents were allowed to react with alkyl 2-furyl ketones (371), 1,2-, 1,4- and 1,6-addition products were observed (Scheme 100). The 1,4-addition products (372) were oxidized by air during the work-up procedure to yield (373) and (374) <80ACS(B)435). 

Furyl ketones can be easily obtained by Friedel-Crafts acylation of furans. They can also be obtained from derivatives of furan-2-carboxylic acid such as the amides, nitriles and chlorides by literature reactions. The 3-furyl ketones are also obtained by similar methods. 

Treatment of 2-(l,2-dibromoethenyl)quinoxalines 57 with Na2CS3 affords thieno[2,3- ]quinoxalines 59. Addition of the thiocarbonate to the side chain generates 58. Intramolecular cyclization of 58 with loss of CS2 and NaBr leads to 59 (Scheme 14) <2001J(P1)154>. Azulenothiophenes 61 are prepared from azulene derivatives 60 by the reaction with thioacetamide (Scheme 15) <2002H(58)405>. Similar reactions of furyl ketones 62 afford thieno[3,4-3]furans 63 <1998JHC71>. 

SYNS (-)-BOTRYODIPLODIN 2-HYDROXY-3-METHYL-4-ACETYLTETRAHYDROFURANE METHYL TETRAHYDRO-5-HYDROXY-4-METHYL-3-FURYL KETONE l-(TETRAHYDRO-5-HYDROXY-4-METHYL-3-FURANYL)-ETHANONE (9CI)... 

SYNS DB 138 3,5-DIIODO-4-HYDROXYPHENYL 5-ETHYL-2-FURYL KETONE KETONE, 3,5-DIIODO-4-HYDROXYPHENYL 5-ETHYL-2-FURYL... 

DIIODO-4-HYDROXYPHENYL2,5-DIMETHYL-3-FURYL KETONE see DNF450... 

DIIODO-4-HYDROXYPHENYL5-ETHYL-2-FURYL KETONE see EID250... 

N-acylaziridines occurs on treatment with triphenylphosphine with the formation of the ylides (67), thereby providing a route to a-substituted primary allylic amines via their in situ reactions with aldehydes.The reactions of triphenylphosphine with epoxides in phenolic media provide a new access to the vinyl-phosphonium salts (68). A route to 1-hydroxyalkylphosphonium salts is provided by the reactions of trimethyl- or triethyl-phosphine with aldehydes or ketones in the presence of anhydrous acids. The related 1-trimethylsiloxyalkylphosphonium salts can be isolated in the presence of trimethylsilyl chloride.Further Wittig-products have been isolated from the reaction of 1,2,3-indanetrione with triphenylphosphine, and, in related work, it has been shown that furoin is deoxygenated on heating with triphenylphosphine to form 2-furfuryl(2-furyl)ketone and triphenylphosphine oxide.The structure of the blue product from the reaction of triphenylphosphine with 2,3,5,6-tetracyano-7-oxabicyclo(2,2,1]hepta-2,5-diene has now been shown by X-ray techniques to be the stable ylide (69). ... 

In most aryl ketones the n -> k triplet is similar in energy to the lowest 7t —> 7r triplet and is responsible for the subsequent transformations those ketones with n ->n as the lowest triplet state are relatively unreactive photochemically. Alkyl furyl ketones belong to this last group their photochemical activity is centerd on the furan double bonds rather than on the carbonyl group. This is consistent with the long-lived phosphorescence exhibited by such compounds. 2-Acetylfuran, for example gives with methyl-propene a mixture in which the main isomer has structure 5.14 By contrast, the addition of dimethylbutene to 2-benzoylfuran discloses a return to the... 

Beckmann rearrangements applied to 2-furyl ketones are abortive there is no skeletal rearrangement. Many studies have failed to elucidate exactly what happens, but recently it has been demonstrated by methods including alternative synthesis that the products from oxime tosylates in methanol are actually 2,5-dimethoxy-2,5-dihydrofurans (e.g., Ill from 2-acetylfuran) as mixtures of geometrical isomers exactly as if they had been formed by furan oxidation techniques Section VI Part I).226... 

Condensation of unsymmetrical ketones with methyl cyanoacetate usually gives a mixture of ( )- and (Z)-isomers in which the isomer with a trans relationship between the bulkier substituent and the car-boalkoxy group predominates. Thus, condensation of alkyl 2-furyl ketones (46) and (47) affords a mixture of ( )- and (Z)-isomers of (48) and (49) with the ( )-isomer predominating (Scheme 12). ... 

Propanone, l-(2-furanyl)-, l-(2-furyl)propan-l-one, ethyl 2-furyl ketone, 2-propanoylfuran, 2-propionylfuran [3194-15-8]... 

The asymmetry in 5-hydroxy-5,6-dihydropyran-2-ones, which form the basis of the phomopsolides, is derived from the Noyori asymmetric hydrogenation of a furyl ketone. The resulting furyl alcohol is then stereoselectively transformed into the pyranone <04TL1005>. 

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