- Syntheses and pyrolyses of benzofuran analogues of α-oxo-o- quinodimethane. A study on vinylcarbene-cyclopropene rearrangement
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(Chemical Equation Presented) Flash vacuum pyrolyses (FVP) of benzoic 3-methyl-2-benzofurancarboxylic anhydride (12) and benzoic 2-methyl-3- benzofurancarboxylic anhydride (13) at 550°C and ca. 10-2 torr both give methylenebenzocyclobutenone (21) as the major product and indenone (22) as the minor one. A mechanism involving generation of α-oxo-o- quinodimethane 11 as the primary pyrolysis product from FVP of 13, followed by elimination of a CO molecule to give carbene 24, which undergoes a vinylcarbene-cyclopropene rearrangement and a ring contraction of the resulting carbene 23, is proposed to account for the observed results. The proposed mechanism is further supported by a deuterium-labeling study on FVP of (2-benzofuryl)methyl-α,α-d2 benzoate (28-d2).
- Tseng, Pen-Wen,Yeh, Su-Wen,Chou, Chin-Hsing
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p. 3481 - 3485
(2008/09/21)
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- 6-(Aryl-amido or aryl-amidomethyl)-naphthalen-2-yloxy-acidic derivatives as inhibitors of plasminogen activator inhibitor type-1 (PAI-1)
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This invention provides novel compounds, pharmaceutical compositions and methods of treating thrombotic disorders in mammals, the compounds having the formula: Wherein: Ar is phenyl, naphthyl, furanyl, benzofuranyl, indolyl, pyrazolyl, oxazolyl, fluorenyl, phenylcycloalkane where the cycloalkane can be cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl and Ar can be optionally substituted by 1 to 3 groups selected from C1-C6 alkyl, C1-C6 alkoxy, hydroxy, phenyl-(CH2)0-6—, phenyl-(CH2)0-6O—, C3-C6 cycloalkyl, —(CH2)—C3-C6 cycloalkyl, halogen, C1-C3 perflouroalkyl and C1-C3 perfluoroalkoxy where phenyl can be substituted with from 1 to 3 groups selected from C1-C6 alkyl, C1-C6 alkoxy, phenyl, halogen, trifluoromethyl or trifluoromethoxy; R1 is hydrogen, C1-C6 alkyl or phenyl-(CH2)1-6— where phenyl can be substituted with C1-C6 alkyl, C1-C6 alkoxy, halo, trifluoromethyl or trifluoromethoxy; R2 and R3 are H, C1-C6 alkyl, phenyl-(CH2)0-3—, halo and C1-C3 perfluoroalkyl where phenyl can be substituted with C1-C6 alkyl, C1-C6 alkoxy, halo, trifluoromethyl or trifluoromethoxy; R4 is —CHR5CO2H or —CH2-tetrazole where R5 is H or benzyl; and n=0 or 1; or a pharmaceutically acceptable salt or ester form thereof.
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- A New Preparation of Benzofurans Utilizing Trimethylsilyldiazomethane
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o-Triisopropylsiloxyaryl ketones and aldehydes smoothly reacted with the lithium salt of trimethylsilyldiazomethane to give o-triisopropylsiloxyphenylacetylenes which were easily converted to benzofurans by treatment with tetra-n-butylammonium fluoride. 3-Benzofuranmethanols were also obtained when the reaction was conducted in the presence of carbonyl compounds.
- Ito, Yasuko,Aoyama, Toyohiko,Shioiri, Takayuki
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p. 1163 - 1164
(2007/10/03)
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- Preparation of 2,3-Dimethylene-2,3-dihydrobenzofuran by the Flash Vacuum Pyrolysis of (2-Methyl-3-benzofuryl)methyl Benzoate
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Pyrolysis of (2-methyl-3-benzofuryl)methyl benzoate (7) gives a 30percent yield of two dimers of 2,3-dimethylene-2,3-dihydrobenzofuran (4), a dimer 12 and a dimer (13), in a ratio of 4.1 to 1.It is shown, by low-temperature 1H-NMR spectroscopy, that the primary pyrolysis product from 7 is 4, which forms 12 and 13 upon warming.The structure of the dimer 12 is confirmed by a deuterium-labeling experiment.Compound 4 can be trapped with methyl acrylate to form a 3.0 to 1 ratio of two Diels-Alder adducts.
- Chou, Chin-Hsing,Trahanovsky, Walter S.
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p. 4208 - 4212
(2007/10/02)
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