1,4-dioxaspiro[4.5]deca-6,9-dien-2,8-dione durch anodische oxidation von 4-methoxyphenoxyessigsäuren

On preparative anodic oxidation in acetonitrile at graphite electrodes 4-methoxyphenoxyacetic acids 1 cyclize to 1,4-dioxaspiro [4.5] deca-6,9--dien-2,8-diones 2. Electroanalytical results are given.     

Synthese des 6- und 7-Methyl-spiro[4.5]deca-6,9-dien-8-ons

Zusammenfassung Es werden die Synthesen folgender Verbindungen beschrieben: -(4-Hydroxy-3-methylphenyl)buttersäure, 4-(4-Hydroxy-3-methylphenyl)-1-butanol, 7-Methyl-spiro[4.5]deca-6,9-dien-8-on, -(4-Hydroxy-2-methylphenyl)buttersäure und dessen Methylester, 4-(4-Hydroxy-2-methylphenyl)-1-butanol und 6-Methyl-spiro[4.5]deca-6.9-dien-8-on.

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The synthesis of the following compounds is described: -(4-hydroxy-3-methylphenyl)-butyric acid, 4-(4-hydroxy-3-methylphenyl)-butanol-(1), 7-methyl-spiro[4.5]deca-6.9-dien-8-one, -(4-hydroxy-2-methylphenyl)-butyric acid and its methyl ester, 4-(4-hydroxy-2-methylphenyl)-butanol-(1) and 6-methyl-spiro[4.5]deca-6.9-dien-8-one.

     

Synthesis of 1-substituted 2-azaspiro[4.5]deca-6,9-diene-8-ones and 2-azaspiro[4.5]deca-1,6,9-triene-8-ones by a three-component condensation of 1,2,3-, 1,2,4- or 1,3,5-trimethoxybenzene with isobutyric aldehyde and nitriles

A three-component condensation of 1,2,3- or 1,2,4-trimethoxybenzene with isobutyric aldehyde and alkyl cyanoacetates in the presence of sulfuric acid resulted in the formation of substituted 2-azaspiro[4.5]deca-6,9-diene-8-ones. The same reaction of aromatic nitriles yielded 2-azaspiro[4.5]deca-1,6,9-triene-8-ones; in the case of 1,2,3-trimethoxybenzene corresponding Ritter amides were also observed. The condensation of 1,3,5-trimethoxybenzene with isobutyric aldehyde and alkyl cyanoacetates provided the compounds of the formal Knöevenagel condensation.     

Synthesis of 1-substituted 2-azaspiro[4.5]deca-6,9-dien-8-ones and 2-azaspiro[4.5]deca-1,6,9-trien-8-ones by condensation of 2,6-dimethylphenol with isobutyraldehyde and nitriles

1-Substituted 3,3,7,9-tetramethyl-2-azaspiro[4.5]deca-6,9-dien-8-ones and 3,3,7,9-tetramethyl-2-azaspiro[4.5]deca-1,6,9-trien-8-ones were synthesized by three-component condensation of 2,6-dimethylphenol with isobutyraldehyde and nitriles in concentrated sulfuric acid.     

A Convenient Synthesis of Spiro[4-n] dione and 2,2-Disubstituted Cyclopentane-1,3-dione System

An efficient, one pot strategy for the synthesis of spiro [4. n]dione and 2,2-disubstituted cyclopentane-1,3-dione has been developed by using ketals and 1,2-disilyloxycyclobutene in the presence of excess BF ₃.Et₂O.     

Synthesis of 5,8-dihydroxynaphtho[2,3-c][1,2,5]thiadiazole-6,9-dione and 6,9-dihydroxybenzo[g]quinoxaline-5,10-dione

The synthesis of 5,8-dihydroxynaphtho[2,3-c][1,2,5]thiadiazole-4,9-dione 3 , 6,9-dihydroxybenzo[g]quinoxaline-5,10-dione 4 , and their lesser oxygenated analogs via Friedel-Crafts and Diels-Alder synthesis is reported.     

Solid-state polymerization studies of conjugated diacetylenes deca-2,8-diene-4,6-diyne-1,10-diol and derivatives

The title diacetylenic compound (D3) and its derivatives dibenzoate (D3B), dinitrobenzoate (D3mNB), ditosylate (D3PTS), and diurethane (D3PU) were synthesized and their solid-state reactivity examined under irradiation and thermal stimulation. D3, D3B, and D3PTS crystallized in reactive phases. The thermal and irradiation polymerization behavior of D3 and D3B was examined further by time-conversion curves.     

Cis,anti, cis-Tricyclo[5.3.0.02,6]deca-4,9-dione

The chemical behavior and some physical properties (dipole moment, IR. vs. Raman spectra) of the titled compound are not fully consistent with a strictly centrosymmetric structure which might be expected for the anti configuration. The carbonyl groups are less reactive toward nucleophilic reagents and sp² → sp³ transformations as compared to cyclopentanone systems.