Hans-Werner Schmidt
University of Graz
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Monatshefte Fur Chemie | 1981
Gerald Koitz; Walter M. F. Fabian; Hans-Werner Schmidt; Hans Junek
The synthesis of several 2-aminopyridines is described. The reaction of tetracyanoethylene with 3-imino-propane-carbonitrile gives 2-amino-3,4,5-tricyano-pyridines with alkyl and aryl-substituents, resp., in position 6. Nucleophilic substitution of 2-amino-6-chloro-3,5-dicyanopyridines and 2-amino-6-chloro-3,4,5-tricyano-pyridines with phenolates leads to a variety of pyridines. Spectroscopical data of absorption and fluorescence are presented and the influence of the cyano groups is discussed. The results are in good agreement with quantum chemical calculations (PPP).
Monatshefte Fur Chemie | 1986
Hans-Werner Schmidt; Renate Dworczak
Syntheses of 3- and 4-monohalogenated (2a, b; 3a–c; 4a–e) and 3,4-dihalogenated (4f–l) ethyl 5-cyano-salicylates are described. Nitration of the ethyl 5-cyano-4-halo-salicylates3a, b leads to the ethyl 5-cyano-4-halo-3-nitro-salicylates5a, b. Hydrolysis of the ester and cyano group as well as reactions of various chloroformates, N,N-dimethylcarbamyl chloride and acetic anhydride with the hydroxyl group have been studied.
Monatshefte Fur Chemie | 1989
Hans-Werner Schmidt
SummaryBase-catalyzed cyclization of ethoxymethylenemalononitrile2 with substituted acetoacetates1 a–c leads to the ethyl benzoates3 a–c. Depending on the reaction conditions either ethyl 4-aminobenzoates3 d–i or ethyl 4-(2,2-dicyanethylene)aminobenzoates4 d–h are available from2 and the 4-oxyacetoacetates1 d–i. The preparation of the acetoacetates1 a–c and1 g–i is also described.
Monatshefte Fur Chemie | 1988
Hans-Werner Schmidt; Margarete Kores
Reaction of ethoxymethylenemalononitrile with ethyl 4-phenylacetoacetate leads to ethyl 1,1′-biphenyl-6-amino-5-cyano-2-hydroxy-3-carboxylate (3). Acid or basic hydrolysis of the ester and cyano group of3 affords the new derivatives4,5 and6.7 a, b are obtained bySandmeyer-reaction of3. Basic hydrolysis of7 a gives the 3,5-dicarboxylic acid derivative8.
Monatshefte Fur Chemie | 1987
Hans-Werner Schmidt
The synthesis of several new derivatives of 2-amino-4-hydroxybenzonitrile2 and their herbicidal screening data are described. Thus, halogenation and furtherSandmeyer-Reaction of2 leads to the 2,3,5-trihalogenated derivatives5 a–e. Reaction of ethyl chloroformate with the amino group of2 gives6 a, acylation7 a, b and8. The 3,5-dihalogenated compounds10 a–e are obtained from6 a and7 a, b by bromination or iodation. The hydroxyl group of6 a, 7 a, b and10 a, c, e reacts with N,N-disubstituted carbamyl chlorides to give6 c, d, 9 a, b, 11, 12 and13 a, b.
Monatshefte Fur Chemie | 1970
G. Zigeuner; Hans-Werner Schmidt; D. Volpe
ZusammenfassungAcylierung der Dihydro-2(1H)-pyrimidinone (-thione) gibt 6-(2′-Oxoalkyl)dihydro-2(1H)-pyrimidinone (-thione).AbstractAcylation of the dihydro-2(1H)-pyrimidinones (-thiones) gives 6-(2′-oxoalkyl)dihydro-2(1H)-pyrimidinones (-thiones).
Journal of Heterocyclic Chemistry | 1987
Hans-Werner Schmidt; Gerald Koitz; Hans Junek
Organic Preparations and Procedures International | 1988
Hans-Werner Schmidt; Manfred Klade
European Journal of Organic Chemistry | 1983
Hans-Werner Schmidt; Rudolf Schipfer; Hans Junek
European Journal of Organic Chemistry | 1988
Hans-Werner Schmidt; Manfred Klade