4-acetylphenyl-

In further work from Vbgtle s laboratory, a number of novel krakenmoleculen (compounds 2-4) were reported to form complexes or inclusion compounds with a variety of molecular guests. The guests included pyridine, DME, chloroacetonitrile and a number of other substances. The general formula for these compounds is shown below. The substituents (R) reported in this paper were numerous and included 2-for-mylphenyl, 2-acetylphenyl, and 8-quinolinyl. 

Depending upon the structure of the substrates 49, 52, and 56 hexahydropyrido[l,2-n]-[3,l]benzoxazines 50, 54, 2-aminobenzaldehyde 53, 1-substituted piperidones 51, 55, 57, 3,4,5,6-tetrahydropyridinium salt 58, or their mixture was obtained during the oxidation of 1-(2-hydroxymethyl-, 2-formyl- and 2-acetylphenyl)piperazines (49, 52, 56) with Hg(II)-EDTA complex (Schemes 6-8) (79AP219, 98ZN(B)37, 98ZN(B)1369). 

The alkaline hydrolyses of 2-formyl and 2-acetylphenyl trans-cinnamates [40] have been studied (Shalitin and Bernhard, 1964). The relatively rapid... 

The use of mesitoate esters in the elucidation of reaction mechanisms has been pioneered by Burrows and Topping (1969,1970). This system has been used to suppress the competitive intermolecular reaction by steric bulk effects and to detect participation by the identification of the products formed. Under identical conditions (pH 11.28 at 30°C in 9.5% ethanol-water), 2-acetylphenyl mesitoate [41]is hydrolysed 130 times more readily than 4-acetylphenyl mesitoate, clearly indicating intramolecular catalysis. However, the products of hydrolysis provided no clue to the mechanism of... 

The use of mesitoic acid esters has again been successfully employed by Burrows and Topping (1975) in the elucidation of intramolecular carbon acid participation. Under basic aqueous conditions, 2-acetylphenyl mesitoate [41] hydrolyses to yield mesitoic acid and 2-hydroxyacetophenone, reacting with intramolecular catalysis via the monoanion of the ketonic hydrate (see p. 192). However, in 47.5% aqueous ethanol containing potassium hydroxide, the reaction products from l-acetyl-2-naphthyl mesitoate [45] were found... 

The formation of triazoles by acid-catalyzed ring opening and isomerization of various other C4-substituted sydnones has also been explored <2001MI769>. When applied to 3-(2-acetylphenyl)sydnone, conditions that are successful for C4 acylation of other 3-arylsydnones result unexpectedly in the formation of the jV-acctyl-3-methylindazole 72. Initial protonation of the carbonyl in the ortho-acetyl group triggers attack by the N2 position of the sydnone ring and concludes with hydrolysis and loss of carbon dioxide (Equation 3) <1996SC2757>. 

The classical synthesis of mesoionic 1,2,3-oxadiazohum-5-olates (3), the so-called sydnones , by Earl and Mackney (42), involving the cyclodehydration of an N-nitrosoglycine derivative, continues to be the only viable method for their preparation. However, Turnbull and co-worker (43) reported that the use of neutral nitrosation conditions avoids the formation of C-nitrosation and allows for the synthesis of previously inaccessible 3-arylsydnones, such as 3-(2-acetylphenyl) sydnone. The method is illustrated below. 

A Baker-Venkataraman rearrangement of 2-acetylphenyl methyl phthalate 753 forms the (3-diketone intermediate 754, which undergoes successive ring closures leading to the formation of benzo[ ]indeno[2.1-< ]pyran-l-,ll-dione 755 in high yield (Scheme 195) <2002TL4515>. 

Treatment of 3-oxo-2,3-dihydrobenzotellurophene with benzenethiol in diethyl ether cleaved the heterocycle forming 2-acetylphenyl phenylthio tellurium. ... 

Acetylphenyl Phenylthio Tellurium1 0.5 g (2.0 mmol) of 3-oxo-2,3-dihydrobenzotellurophene and benzenethiol are added to a small volume of diethyl ether, the mixture is stirred vigorously for 1 h at 20°, and then extracted with chloroform. The organic extract is evaporated and the residue is recrystallized from heptane yield 0.35 g (50%) m.p. 105°. 

Acetylphenyl tellurium halides were formed in 50% yield when 3-oxo-2,3-dihydro-1-benzotellurophenes dissolved in diethyl ether were stirred at 20° with aqueous hydrohalic acids . 

Acetylphenyl Tellurium Halides1 0.5 g of the henzotellurophcnc derivative are dissolved in the minimum amount of diethyl ether at 20. Concentrated aqueous hydrohalic acid is added, the mixture is vigorously stirred for 1 h, and extracted with chloroform. The extract is evaporated and the residue is recrystallized from ethanol. 

Acetylphenyl tellurium bromides and acetylthienyl tellurium bromides condensed with dimethoxydimethylaminomethane or -ethane in refluxing xylene1. 

Methyl 2-(3 -Phenyl-2 -propen-r-oyl)phenyl Tellurium3 A stirred mixture of 12 g (46 mmol) of 2-acetylphenyl methyl tellurium, 17.6 m/(18.4 g, 170 mmol) of benzaldehyde, 88 mlof acetic acid, and 35 ml of piperidine is heated under reflux for 6 h. The mixture is then steam-distilled to remove unreacted benzaldehyde. The resultant red oil is separated by extraction with chloroform, the extract is evaporated, and the residue is fractionally distilled under vacuum. The fraction boiling above 200°/0.1 torr is collected and redistilled to give a condensate that should solidify. This solid is recrystallized several times from a mixture of petroleum ether and benzene yield 3.2 g (20%) m.p. 102-104° (from heptane/benzenc). 

Acetylphenyl butyl tellurium is formylated at the acetyl-methyl group by methyl formate and sodium in diethyl ether. The formyl compound is converted to butyl 2-(diazoacetyl)-phenyl tellurium upon treatment with 4-methylbenzenesulfonyl azide1. The diazoacetyl group is converted to the dibromoacetyl group by bromine in diethyl ether1. 

Acetylphenyl cthoxycarbonylmethyl tellurium, 2-acetylphenyl phenyl tellurium, and 2-methoxycarbonylphenyl phenyl tellurium lost the alkyl or phenyl groups in refluxing acetic acid containing 30% hydro bromic acid5-7. 

Similarly prepared were 2-acetylphenyl dimethyl telluronium iodide (90% yield m.p. 145-150°) and 4-acetylphenyl dimethyl telluronium iodide (80% yield m.p. 151-154°) from the corresponding dimethylene acetals4. 

Acetylphenyl tellurium bromide condensed intramolecularly in ethanolic potassium hydroxide to yield 3-oxo-2,3-dihydrobenzotellurophene2,3. 

Oxo-2,3-dihydrobenzotellurophcnc2 5.0 g (15 mmol) of 2-acetylphenyl tellurium bromide is dissolved in 100 ml of ethanol, 0.85 g (15 mmol) of potassium hydroxide dissolved in ethanol are added, the mixture is stirred, and then poured into 200 ml of water. The precipitate is filtered ofT and rccrystallized from cyclohexane yield 3.0 g (80%) m.p. 107°. 

When 2-acetylphenyl tellurium bromide and aromatic aldehydes were refluxed in acetic acid in the presence of piperidine, 2-benzylidene-3-oxo-benzotellurophenes were formed in 80% yields4. These reactions were proposed to proceed via 2-(3-aryl-l-oxoprop-2-en-l-yl)-phenyl tellurium bromides that cyclize with elimination of hydrogen bromide. However, 3-oxo-2,3-dihydrobenzotellurophene cannot be ruled out as the intermediate which then condenses with the aromatic aldehydes2, because 2-acetylphenyl tellurium bromide is known to cyclize to form 3-oxo-2,3-dihydrobenzoteIIurophene2,3. 

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