Karl Eichinger

Spektroskopische untersuchungen von neuen ungewöhnlich oxidationsstabilen kationenradikalen quartärer pyridiniumverbindungen

Abstract The novel compounds 1,1″-dimethyl[4,2′;4′,4″]terpyridiniumdiperchlorate ( 6 ), 1,1′,1″-trimethyl[4,2′;4′,4″]terpyridiniumtriperchlorate ( 7 ) and 1,1″,1‴-trimethyl[4,2′;4′,4″;6′,4‴]quaterpyridinium-triperchlorate ( 8 ) were synthesized. ( 6 ) and ( 8 ) give, upon reduction with Zn, stable radical cations which were investigated by [ 1 H]NMR-, vis- and ESR-spectroscopy and cyclovoltammogrammes.

A CONVENIENT SYNTHESIS OF 3- AND 3,4-SUBSTITUTED 4,5-DIHYDROISOXAZOLE-5-ACETIC ACIDS

Abstract The 4,5-dihydroisoxazole-5-acetic acids 4a-j were prepared from the ketoximes 1a-j, 2,2-dimethyl-5-methoxymethylene-1,3-dioxan-4,6-dione (2) and butyllithium in yields from 35 to 79%.

Synthesen von 2-Anilinocyclopentanonen

The syntheses of the 2-anilinocyclopentanones2 a–2 e in yields about 50% by reaction of 2-chlorocyclopentanone with 4-chloroaniline, N-methyl-4-chloroaniline, α,α,α-trifluoro-3-toluidine, N-methyl-α,α,α-trifluoro-3-toluidine and 3,4,5-trimethoxyaniline, are described.

Infrared spectroscopic detection of sulphone groups in doped polybenzo[c]thiophenes

Abstract By reaction of 1,3-dihydrobenzo[c]thiophene with FeCl 3 , air or TCNQ the oxidatively doped polybenzo[c]thiophenes ( 1a , b , d , e ) were prepared. Their infrared spectra showed two strong absorptions in the ranges 1265–1337 cm −1 and 1142–1184 cm −1 . Efficient drying did not change these absorptions but reaction of 1a , b , d , e with LiAlH 4 resulted in their decrease to weak bands. According to these results and by comparison with the infrared spectra of reference compounds data, 1a—e were found to contain sulphone groups.

Synthese von 3,3-Dialkyl-2-phenylacetylcyclopentanonen

Syntheses of 3,3-dialkyl-2-phenylacetylcyclopentanones starting from 2,2-disubstituted cyclopentanones are described.

Zum Chemismus der Reaktion von 1-(1-Ethinyl)-6-oxabicylo[3.1.0.]hexanen zu 2-Acylcyclopentanonen

An investigation of the reaction of model compound1 with HCOOH/H2O and CH3COOH/H2O/Dowex 50 to the 1,3-diketone5 is described.

Untersuchungen über die Bildung von 2-Acylcyclopentanonen aus 1-(1-Äthynyl)-cyclopentenen und Perameisensäure

The reaction of1 a with H2O2 in HCOOH yielded 37%4 a and 15%3 a. 1 c reacted under similar conditions to4 c (29%),3 b (12%) and3 c (22%).1 b was less reactive towards H2O2 in HCOOH due to its low solubility in HCOOH;4 b was isolated with 6% yield, 69%1 b remained unchanged.Under conditions of epoxide hydrolysis and catalysis of theRupe rearrangement, the epoxides2 a and2 b yielded 37%4 a and 30%4 b, resp.Based upon these experimental results, mechanisms for the observed reactions are proposed.

A NOVEL BASE PROMOTED REACTION OF METHYL 2-ISOXAZOLINE-5-ACETATES TO 5-(2-OXOETHYL)-3-ISOXAZOLIDINONES

Abstract The 5-(2-aryl-2-oxoethyl)-3-isoxazolidinones 3a-e were prepared from the methyl 3-aryl-2-isoxazoline-5-acetates 2a-e and sodium hexanolate in boiling hexanol in yields from 46 to 86 %. The reaction conditions were optimized and a mechanism for this reaction is proposed and discussed.

p-(5-Fluor-2,4-dinitro-1-phenylazo)-N,N-dimethylanilin, ein neues Reagens zur flüssigchromatographischen Bestimmung von Phenolen

The synthesis ofp-(5-fluoro-2,4-dinitro-1-phenylazo)-N,N-dimethylaniline and its reactions with phenoles top-(2,4-dinitro-5-phenoxy-1-phenylazo)-N,N-dimethylanilines and the use of the resulting coloured products for the TLC determination of phenoles is described.

Stereochemie vonGrignard-Reaktione mit 2-(N-Methylanikino)-cyclopentanonen

TheGrignard reactions of the 2-anilinocyclopentanones (1 a and1 b) with CH3MgI and C6H5C≡CMgBr, giving the 2-anilinocyclopentanols2 a, 2 b, and2 c, and the synthesis oftrans-1-methyl-2-(4-chloro-N-methylanilino)-cyclopentanol (4), which was used as a reference compound of known stereochemistry, are described. IR spectroscopic investigations of2 a, 2 b, and2 c as compared with4 lead to the conclusion that2 a, 2 b, and2 c have the structures ofcis-2-(N-methylanilino)-cyclopentanols.