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Papers by Matthias Rehwald
Journal f�r Praktische Chemie/Chemiker-Zeitung, 1996
Synthesis and Reactions of 2-Mercapto-6-thioxo-thiopyran-3-carboxylate derivatives Abstract. 6-Am... more Synthesis and Reactions of 2-Mercapto-6-thioxo-thiopyran-3-carboxylate derivatives Abstract. 6-Amino-thiopyran-2-thiones (1) react with dihydrogen sulfide in the presence of pyridine and triethyl amine to yield 6-thioxo-thiopyran-2-thiolates (2). Methylation of 2 gives the methylthio compounds 3 and 4. Further methylation of 3a and 4a yields the thiapyrylium salt (7). The reaction of 2-imino-thiopyran (6) with carbon disulfide represents another route to the 6-methylthio-thiopyran-2-thione (4a). The 2-methylthio-thiopyran-6-thione (3a) undergoes substitution of the methylthio group with amines to 8 or reacts with phenylhy-drazine to phenylhydrazono-thiopyrane (9c). 6-Thioxo-thiophen-Zthiolates (2a,b) react with hydrazine hydrate to give hydrazono-thiopyranes (lOa,b) which can be S-methylated. On the contrary 2c gives with hydrazine hydrate under ring transformation the pyridine-Zthiolate (11). N,S-Acetals (12) and 1,3,4-thiadiazoles (15), which give rise to new pyridine derivatives (14) and (17), can be obtained from 1-Amino-pyridin-2-thiolate (11).
ChemInform, 2010
3-Amino-2(1H)-quinolones by Cyclization of N-Acylated Anthranilic Acid Derivatives.-Haloacetylate... more 3-Amino-2(1H)-quinolones by Cyclization of N-Acylated Anthranilic Acid Derivatives.-Haloacetylated compounds (I) are treated with various secondary amines giving 2-aminoacetyl compounds (III), which are subjected to the Thorpe-Ziegler cyclization to obtain title compounds (IV). The heterocondensed pyridones (X) are obtained analogously. Quinolone (IVa) is subjected to Cl/OH exchange to give chloroquinoline (V) which is convenient for consecutive reactions.
Monatshefte f�r Chemie Chemical Monthly, 1995
Pyridinium and sulfonium salts 2a-e which can be prepared from 3-amino-2-(~-haloacetyl)crotonitri... more Pyridinium and sulfonium salts 2a-e which can be prepared from 3-amino-2-(~-haloacetyl)crotonitriles and 3-amino-2-(~-halo-acetyl)-3-phenyl-acrylonitriles react with malononitrile in the presence of a base to 3-amino-2-pyridinio-phenolates 3a,b and 3-amino-2-sulfonio-phenolates 3c-e. In an analogous way, 3-amino-2-(diethyloxyphosphoryl)-phenol 5a and 3-amino-2-(p-tolyl-sulfonyl)phenol 5b have been prepared. 2,3-Diamino-phenoles 6a,b are formed from the pyridinium salts 3a,b. The behaviour of the pyridinium salts 2a,b towards heterocumulenes has been investigated. Cyanamide leads to the (2-amino-4-hydroxy-pyrid-3-yl)-pyridinium salt 8e. Phenylisothiocyanate gives the 3-pyridinio-2-thioxo-pyridin-4-olates 9a,b. Carbon disulfide gives rise to 3-pyridinio-2-thioxo-pyridin-4-olate 10 or 3-pyridinio-2-thioxo-thiopyran-4-olate 11, depending on the substituent at the 6-position. Phenylisocyanate reacts to the pyrimidin-2,4-dione 12 with loss of N-methyl-pyridinium chloride. S-methylation of 9a and cleavage of the pyridine moiety yields the 3-amino-2-methylthio-pyrid-4-one 14. The structures were investigated by 1H and 13C NMR spectroscopy.
HETEROCYCLES, 1997
Reaction of secondary amines with the N-(iodoacety1)authranilic acid derivatives, 2-(iodoacetylam... more Reaction of secondary amines with the N-(iodoacety1)authranilic acid derivatives, 2-(iodoacetylamino)acetophenone and 2-(iodoacety1amino)benzophenone yields 3-amino-2(lf+quinolones in two steps. Analogously
HETEROCYCLES, 2000
Abstract; N-Chloroacetylanthranilic acid ethyl ester reacts with potassium thiocyanate in the pre... more Abstract; N-Chloroacetylanthranilic acid ethyl ester reacts with potassium thiocyanate in the presence of alcohol to give the (4-oxo-3, 4-dihydroquinazolin-2-yl-sulfanyl) acetic acid ester (3a). In the presence of water or amines the acetic acid derivative (3b) or the acetamide ...
Liebigs Annalen der Chemie, 1993
Hetarylsulfonium Salts by Cyclization Reaction of tetrahydrothiophene with the N-(iodoacetyl)anth... more Hetarylsulfonium Salts by Cyclization Reaction of tetrahydrothiophene with the N-(iodoacetyl)anthranilic acid derivatives 1a, b and 2-(iodoacetylamino)acetophenone (1c) yields the 1-(2-oxoquinolin-3-yl)tetrahydrothiophenium salts 3a–c in two steps. Analogously the heterocondensed 1-(2-oxopyridin-3-yl)tetrahydrothiophenium salts 6 and 7 can be prepared. The 1-(3-oxopyridazin-4-yl)- and 1-(2-oxopyridin-3-yl)tetrahydrothiophenium salts 10, 13, 16, 18 are synthesized on the same way. From the tetrahydrothiophenium salt 3a the 3-(alkylthio)-4-aminoquinolin-2(1H)- ones 19 arise.
Journal für praktische Chemie, 2000
Abstract 1-(3-Coumaryl)-pyridinium salts 3 and 1-(3-coumaryl)-tetrahydrothiophenium salts 5 were ... more Abstract 1-(3-Coumaryl)-pyridinium salts 3 and 1-(3-coumaryl)-tetrahydrothiophenium salts 5 were synthesized from 2-acylphenyl chloro-or bromoacetates 2. 2-Chloro-N 1-(3, 4-dimethoxyphenyl)-acetamide and substituted 2-chloro-N 1-(2-thienyl)-acetamides 8 react ...
ChemInform, 2010
Synthesis of Hetaryl Pyridinium Salts and Fused 3-Amino-pyrid-2-ones.-Pyridine is alkylated by th... more Synthesis of Hetaryl Pyridinium Salts and Fused 3-Amino-pyrid-2-ones.-Pyridine is alkylated by the halo compounds (I) to give the corresponding pyridinium salts which are immediately cyclized by an unusual Knoevenagel reaction. Cyclization of (IV) is achieved in two ways. The base catalyzed reaction of (IV) yields the cyclization product (V) in very good yield. A known reaction of 2-acyl-N-chloroacetylanilines with pyridine proceeds also for (VIII). Thiophenes (X) are reacted with pyridine as well but further reaction by means of Thorpe-Ziegler-cyclization fails. However, treatment of (XI) with bases yields pyridiniumolates (XII) which are further transformed into fused thienopyridinones (XIII) by heating.-(REHWALD, MATTHIAS;
Journal f�r Praktische Chemie/Chemiker-Zeitung, 1996
Synthesis and Reactions of 2-Mercapto-6-thioxo-thiopyran-3-carboxylate derivatives Abstract. 6-Am... more Synthesis and Reactions of 2-Mercapto-6-thioxo-thiopyran-3-carboxylate derivatives Abstract. 6-Amino-thiopyran-2-thiones (1) react with dihydrogen sulfide in the presence of pyridine and triethyl amine to yield 6-thioxo-thiopyran-2-thiolates (2). Methylation of 2 gives the methylthio compounds 3 and 4. Further methylation of 3a and 4a yields the thiapyrylium salt (7). The reaction of 2-imino-thiopyran (6) with carbon disulfide represents another route to the 6-methylthio-thiopyran-2-thione (4a). The 2-methylthio-thiopyran-6-thione (3a) undergoes substitution of the methylthio group with amines to 8 or reacts with phenylhy-drazine to phenylhydrazono-thiopyrane (9c). 6-Thioxo-thiophen-Zthiolates (2a,b) react with hydrazine hydrate to give hydrazono-thiopyranes (lOa,b) which can be S-methylated. On the contrary 2c gives with hydrazine hydrate under ring transformation the pyridine-Zthiolate (11). N,S-Acetals (12) and 1,3,4-thiadiazoles (15), which give rise to new pyridine derivatives (14) and (17), can be obtained from 1-Amino-pyridin-2-thiolate (11).
ChemInform, 2010
3-Amino-2(1H)-quinolones by Cyclization of N-Acylated Anthranilic Acid Derivatives.-Haloacetylate... more 3-Amino-2(1H)-quinolones by Cyclization of N-Acylated Anthranilic Acid Derivatives.-Haloacetylated compounds (I) are treated with various secondary amines giving 2-aminoacetyl compounds (III), which are subjected to the Thorpe-Ziegler cyclization to obtain title compounds (IV). The heterocondensed pyridones (X) are obtained analogously. Quinolone (IVa) is subjected to Cl/OH exchange to give chloroquinoline (V) which is convenient for consecutive reactions.
Monatshefte f�r Chemie Chemical Monthly, 1995
Pyridinium and sulfonium salts 2a-e which can be prepared from 3-amino-2-(~-haloacetyl)crotonitri... more Pyridinium and sulfonium salts 2a-e which can be prepared from 3-amino-2-(~-haloacetyl)crotonitriles and 3-amino-2-(~-halo-acetyl)-3-phenyl-acrylonitriles react with malononitrile in the presence of a base to 3-amino-2-pyridinio-phenolates 3a,b and 3-amino-2-sulfonio-phenolates 3c-e. In an analogous way, 3-amino-2-(diethyloxyphosphoryl)-phenol 5a and 3-amino-2-(p-tolyl-sulfonyl)phenol 5b have been prepared. 2,3-Diamino-phenoles 6a,b are formed from the pyridinium salts 3a,b. The behaviour of the pyridinium salts 2a,b towards heterocumulenes has been investigated. Cyanamide leads to the (2-amino-4-hydroxy-pyrid-3-yl)-pyridinium salt 8e. Phenylisothiocyanate gives the 3-pyridinio-2-thioxo-pyridin-4-olates 9a,b. Carbon disulfide gives rise to 3-pyridinio-2-thioxo-pyridin-4-olate 10 or 3-pyridinio-2-thioxo-thiopyran-4-olate 11, depending on the substituent at the 6-position. Phenylisocyanate reacts to the pyrimidin-2,4-dione 12 with loss of N-methyl-pyridinium chloride. S-methylation of 9a and cleavage of the pyridine moiety yields the 3-amino-2-methylthio-pyrid-4-one 14. The structures were investigated by 1H and 13C NMR spectroscopy.
HETEROCYCLES, 1997
Reaction of secondary amines with the N-(iodoacety1)authranilic acid derivatives, 2-(iodoacetylam... more Reaction of secondary amines with the N-(iodoacety1)authranilic acid derivatives, 2-(iodoacetylamino)acetophenone and 2-(iodoacety1amino)benzophenone yields 3-amino-2(lf+quinolones in two steps. Analogously
HETEROCYCLES, 2000
Abstract; N-Chloroacetylanthranilic acid ethyl ester reacts with potassium thiocyanate in the pre... more Abstract; N-Chloroacetylanthranilic acid ethyl ester reacts with potassium thiocyanate in the presence of alcohol to give the (4-oxo-3, 4-dihydroquinazolin-2-yl-sulfanyl) acetic acid ester (3a). In the presence of water or amines the acetic acid derivative (3b) or the acetamide ...
Liebigs Annalen der Chemie, 1993
Hetarylsulfonium Salts by Cyclization Reaction of tetrahydrothiophene with the N-(iodoacetyl)anth... more Hetarylsulfonium Salts by Cyclization Reaction of tetrahydrothiophene with the N-(iodoacetyl)anthranilic acid derivatives 1a, b and 2-(iodoacetylamino)acetophenone (1c) yields the 1-(2-oxoquinolin-3-yl)tetrahydrothiophenium salts 3a–c in two steps. Analogously the heterocondensed 1-(2-oxopyridin-3-yl)tetrahydrothiophenium salts 6 and 7 can be prepared. The 1-(3-oxopyridazin-4-yl)- and 1-(2-oxopyridin-3-yl)tetrahydrothiophenium salts 10, 13, 16, 18 are synthesized on the same way. From the tetrahydrothiophenium salt 3a the 3-(alkylthio)-4-aminoquinolin-2(1H)- ones 19 arise.
Journal für praktische Chemie, 2000
Abstract 1-(3-Coumaryl)-pyridinium salts 3 and 1-(3-coumaryl)-tetrahydrothiophenium salts 5 were ... more Abstract 1-(3-Coumaryl)-pyridinium salts 3 and 1-(3-coumaryl)-tetrahydrothiophenium salts 5 were synthesized from 2-acylphenyl chloro-or bromoacetates 2. 2-Chloro-N 1-(3, 4-dimethoxyphenyl)-acetamide and substituted 2-chloro-N 1-(2-thienyl)-acetamides 8 react ...
ChemInform, 2010
Synthesis of Hetaryl Pyridinium Salts and Fused 3-Amino-pyrid-2-ones.-Pyridine is alkylated by th... more Synthesis of Hetaryl Pyridinium Salts and Fused 3-Amino-pyrid-2-ones.-Pyridine is alkylated by the halo compounds (I) to give the corresponding pyridinium salts which are immediately cyclized by an unusual Knoevenagel reaction. Cyclization of (IV) is achieved in two ways. The base catalyzed reaction of (IV) yields the cyclization product (V) in very good yield. A known reaction of 2-acyl-N-chloroacetylanilines with pyridine proceeds also for (VIII). Thiophenes (X) are reacted with pyridine as well but further reaction by means of Thorpe-Ziegler-cyclization fails. However, treatment of (XI) with bases yields pyridiniumolates (XII) which are further transformed into fused thienopyridinones (XIII) by heating.-(REHWALD, MATTHIAS;