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Wolfgang Hanefeld - One of the best experts on this subject based on the ideXlab platform.
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Iminium Carbonic Acid Derivative salts. XII . electrophilic reactions of 2-methylthio-4,5-dihydrothiazolium iodides, 5-methyl-2-methylthiothiazolium iodides and 2-methylthio-5,6-dihydro-1,3-thiazinium iodides. part III. With Vinylogous and Phenylogou
Journal of Heterocyclic Chemistry, 1998Co-Authors: Wolfgang Hanefeld, Helge HarmsAbstract:3-Benzyl-2-memyltmo-4,5-dmydrothiazolium iodide (1), 5-metlyl-2-methylthio-3-phenethylthiazolium iodide (4) and 3-methyl and 3-benzyl-2-methylthio-5,6-dihydro-1,3-thiazinium iodides 7a, b were reacted with the vinylogous doubly activated CH-Acidic compounds 2a-d and the phenylogous doubly activated components 8, 11, 16, 19 and 21 to yield new types of S, N-heterocycles 3, 5, 6, 9, 10, 12, 13, 14, 15 with the partial structure of push-pull substituted butadienes and 17, 18, 20, 22, 23 and 24 with the character of push-pull substituted phenyl ketene S, N-acetals.
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Iminium Carbonic Acid Derivative salts. VIII†. Electrophilic reactions of 2-methylthio-5,6-dihydro-1,3-thiazinium iodides, 2-methylthio-5,6-dihydrothiazolium iodides and 5-methyl-2-methylthiothiazolium iodides. Part II. With active methylene compound
Journal of Heterocyclic Chemistry, 1997Co-Authors: Wolfgang Hanefeld, Helge HarmsAbstract:The title compounds 1a-c and 2 werre reacted with several doubly activated methylene components to yield the cyclic ketene S,N-acetals 3-10.
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iminium Carbonic Acid Derivative salts ix synthesis of n s containing heterobicycles from n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazolium salts part 1 preparation of n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazoliu
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-methylthio-1,3-thiazinium 3 and 2-methylthiothiazolium salts 4,7 obtained from the corresponding 1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide or trimethyloxonium tetrafluoroborate were reacted with vinylogous CH-Acidic compounds forming ketene N,S-acetals 5,6,8,9. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to pyrido[2,1-b]-1,3-thiazines 10 and thiazolo[3,2-b]pyridines 11,12 took place.
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iminium Carbonic Acid Derivative salts xi synthesis of n s containing heterobicycles from n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazouum salts part 3 reaction of n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazolium sa
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-memylthio-1,3-thiazinium 1 and 2-methylthiothiazolium iodides 2, 3 obtained from the corresponding 3,4,5,6-tetrahydro-2H-1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide were reacted with 3-armno-2-cyano-3-arylacrylonitriles forming the cyclic isothioureas 5–7. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to 3,4-dihydro-2H,6H-pyrimido[2,1-b][1,3]thiazines 8a-c, 8a′-c′ and thiazolo[3,2-b]pyrimidines 9a,b, 9a′,b′, 10a,b took place.
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Iminium Carbonic Acid Derivative salts. IX. Synthesis of N,S‐containing heterobicycles from N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazolium salts part 1. Preparation of N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazo
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-methylthio-1,3-thiazinium 3 and 2-methylthiothiazolium salts 4,7 obtained from the corresponding 1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide or trimethyloxonium tetrafluoroborate were reacted with vinylogous CH-Acidic compounds forming ketene N,S-acetals 5,6,8,9. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to pyrido[2,1-b]-1,3-thiazines 10 and thiazolo[3,2-b]pyridines 11,12 took place.
Martin Schlitzer - One of the best experts on this subject based on the ideXlab platform.
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iminium Carbonic Acid Derivative salts ix synthesis of n s containing heterobicycles from n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazolium salts part 1 preparation of n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazoliu
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-methylthio-1,3-thiazinium 3 and 2-methylthiothiazolium salts 4,7 obtained from the corresponding 1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide or trimethyloxonium tetrafluoroborate were reacted with vinylogous CH-Acidic compounds forming ketene N,S-acetals 5,6,8,9. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to pyrido[2,1-b]-1,3-thiazines 10 and thiazolo[3,2-b]pyridines 11,12 took place.
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iminium Carbonic Acid Derivative salts xi synthesis of n s containing heterobicycles from n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazouum salts part 3 reaction of n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazolium sa
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-memylthio-1,3-thiazinium 1 and 2-methylthiothiazolium iodides 2, 3 obtained from the corresponding 3,4,5,6-tetrahydro-2H-1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide were reacted with 3-armno-2-cyano-3-arylacrylonitriles forming the cyclic isothioureas 5–7. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to 3,4-dihydro-2H,6H-pyrimido[2,1-b][1,3]thiazines 8a-c, 8a′-c′ and thiazolo[3,2-b]pyrimidines 9a,b, 9a′,b′, 10a,b took place.
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Iminium Carbonic Acid Derivative salts. XI . Synthesis of N,S‐containing heterobicycles from N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazoüum salts. Part 3. Reaction of N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazoli
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-memylthio-1,3-thiazinium 1 and 2-methylthiothiazolium iodides 2, 3 obtained from the corresponding 3,4,5,6-tetrahydro-2H-1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide were reacted with 3-armno-2-cyano-3-arylacrylonitriles forming the cyclic isothioureas 5–7. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to 3,4-dihydro-2H,6H-pyrimido[2,1-b][1,3]thiazines 8a-c, 8a′-c′ and thiazolo[3,2-b]pyrimidines 9a,b, 9a′,b′, 10a,b took place.
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Iminium Carbonic Acid Derivative salts. IX. Synthesis of N,S‐containing heterobicycles from N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazolium salts part 1. Preparation of N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazo
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-methylthio-1,3-thiazinium 3 and 2-methylthiothiazolium salts 4,7 obtained from the corresponding 1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide or trimethyloxonium tetrafluoroborate were reacted with vinylogous CH-Acidic compounds forming ketene N,S-acetals 5,6,8,9. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to pyrido[2,1-b]-1,3-thiazines 10 and thiazolo[3,2-b]pyridines 11,12 took place.
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Iminiumkohlensäurederivat‐Salze, 7. Mitt. Teil I: Elektrophile Reaktionen von 2‐Methylthio‐5,6‐dihydro‐4H1,3‐thiaziniumiodiden, 2‐Methylthio‐4,5‐dihydrothiazoliumiodiden und 2‐Methylthio‐5‐methylthiazoliumiodiden mit N‐Nucleophilen
Archiv der Pharmazie, 1995Co-Authors: Wolfgang Hanefeld, Helge Harms, Martin SchlitzerAbstract:Cyclische Salze des Dithiokohlensaure-diester-imidium Typs (3, 5) wurden mit NH2-Nucleophilen zu den cyclischen Isothioharnstoffen 6–8 umgesetzt. Einige dieser Verbindungen konnten zu cyclischen Isothioharnstoff-S,S-dioxiden (9, 10) oxidiert werden. Iminium Carbonic Acid Derivative Salts VII, Part I: Electrophilic Reactions of 2-Methylthio-5,6-dihydro-4H-1,3-thiazinium Iodides, 2-Methylthio-4,5-dihydrothiazolium Iodides, and 2-Methylthio-5-methylthiazolium Iodides with N-Nucleophiles Cyclic salts of the dithioCarbonic Acid diester imidium type (3, 5) react with NH2-nucleophiles to the cyclic isothioureas 6–8. Some of these compounds were oxidized to cyclic isothiourea-S,S-dioxides (9, 10).
Helge Harms - One of the best experts on this subject based on the ideXlab platform.
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Iminium Carbonic Acid Derivative salts. XII . electrophilic reactions of 2-methylthio-4,5-dihydrothiazolium iodides, 5-methyl-2-methylthiothiazolium iodides and 2-methylthio-5,6-dihydro-1,3-thiazinium iodides. part III. With Vinylogous and Phenylogou
Journal of Heterocyclic Chemistry, 1998Co-Authors: Wolfgang Hanefeld, Helge HarmsAbstract:3-Benzyl-2-memyltmo-4,5-dmydrothiazolium iodide (1), 5-metlyl-2-methylthio-3-phenethylthiazolium iodide (4) and 3-methyl and 3-benzyl-2-methylthio-5,6-dihydro-1,3-thiazinium iodides 7a, b were reacted with the vinylogous doubly activated CH-Acidic compounds 2a-d and the phenylogous doubly activated components 8, 11, 16, 19 and 21 to yield new types of S, N-heterocycles 3, 5, 6, 9, 10, 12, 13, 14, 15 with the partial structure of push-pull substituted butadienes and 17, 18, 20, 22, 23 and 24 with the character of push-pull substituted phenyl ketene S, N-acetals.
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Iminium Carbonic Acid Derivative salts. VIII†. Electrophilic reactions of 2-methylthio-5,6-dihydro-1,3-thiazinium iodides, 2-methylthio-5,6-dihydrothiazolium iodides and 5-methyl-2-methylthiothiazolium iodides. Part II. With active methylene compound
Journal of Heterocyclic Chemistry, 1997Co-Authors: Wolfgang Hanefeld, Helge HarmsAbstract:The title compounds 1a-c and 2 werre reacted with several doubly activated methylene components to yield the cyclic ketene S,N-acetals 3-10.
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Iminiumkohlensäurederivat‐Salze, 7. Mitt. Teil I: Elektrophile Reaktionen von 2‐Methylthio‐5,6‐dihydro‐4H1,3‐thiaziniumiodiden, 2‐Methylthio‐4,5‐dihydrothiazoliumiodiden und 2‐Methylthio‐5‐methylthiazoliumiodiden mit N‐Nucleophilen
Archiv der Pharmazie, 1995Co-Authors: Wolfgang Hanefeld, Helge Harms, Martin SchlitzerAbstract:Cyclische Salze des Dithiokohlensaure-diester-imidium Typs (3, 5) wurden mit NH2-Nucleophilen zu den cyclischen Isothioharnstoffen 6–8 umgesetzt. Einige dieser Verbindungen konnten zu cyclischen Isothioharnstoff-S,S-dioxiden (9, 10) oxidiert werden. Iminium Carbonic Acid Derivative Salts VII, Part I: Electrophilic Reactions of 2-Methylthio-5,6-dihydro-4H-1,3-thiazinium Iodides, 2-Methylthio-4,5-dihydrothiazolium Iodides, and 2-Methylthio-5-methylthiazolium Iodides with N-Nucleophiles Cyclic salts of the dithioCarbonic Acid diester imidium type (3, 5) react with NH2-nucleophiles to the cyclic isothioureas 6–8. Some of these compounds were oxidized to cyclic isothiourea-S,S-dioxides (9, 10).
Mahmoud Naeeni - One of the best experts on this subject based on the ideXlab platform.
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iminium Carbonic Acid Derivative salts ix synthesis of n s containing heterobicycles from n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazolium salts part 1 preparation of n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazoliu
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-methylthio-1,3-thiazinium 3 and 2-methylthiothiazolium salts 4,7 obtained from the corresponding 1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide or trimethyloxonium tetrafluoroborate were reacted with vinylogous CH-Acidic compounds forming ketene N,S-acetals 5,6,8,9. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to pyrido[2,1-b]-1,3-thiazines 10 and thiazolo[3,2-b]pyridines 11,12 took place.
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iminium Carbonic Acid Derivative salts xi synthesis of n s containing heterobicycles from n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazouum salts part 3 reaction of n protected 2 methylthio 1 3 thiazinium and 2 methylthiothiazolium sa
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-memylthio-1,3-thiazinium 1 and 2-methylthiothiazolium iodides 2, 3 obtained from the corresponding 3,4,5,6-tetrahydro-2H-1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide were reacted with 3-armno-2-cyano-3-arylacrylonitriles forming the cyclic isothioureas 5–7. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to 3,4-dihydro-2H,6H-pyrimido[2,1-b][1,3]thiazines 8a-c, 8a′-c′ and thiazolo[3,2-b]pyrimidines 9a,b, 9a′,b′, 10a,b took place.
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Iminium Carbonic Acid Derivative salts. IX. Synthesis of N,S‐containing heterobicycles from N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazolium salts part 1. Preparation of N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazo
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-methylthio-1,3-thiazinium 3 and 2-methylthiothiazolium salts 4,7 obtained from the corresponding 1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide or trimethyloxonium tetrafluoroborate were reacted with vinylogous CH-Acidic compounds forming ketene N,S-acetals 5,6,8,9. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to pyrido[2,1-b]-1,3-thiazines 10 and thiazolo[3,2-b]pyridines 11,12 took place.
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Iminium Carbonic Acid Derivative salts. XI . Synthesis of N,S‐containing heterobicycles from N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazoüum salts. Part 3. Reaction of N‐protected 2‐methylthio‐1,3‐thiazinium and 2‐methylthiothiazoli
Journal of Heterocyclic Chemistry, 1996Co-Authors: Wolfgang Hanefeld, Mahmoud Naeeni, Martin SchlitzerAbstract:N-Boc-protected 2-memylthio-1,3-thiazinium 1 and 2-methylthiothiazolium iodides 2, 3 obtained from the corresponding 3,4,5,6-tetrahydro-2H-1,3-thiazine-2-thiones and thiazolidine-2-thiones by the action of methyl iodide were reacted with 3-armno-2-cyano-3-arylacrylonitriles forming the cyclic isothioureas 5–7. The protection group was removed with trifluoroacetic Acid whereupon the desired cyclisation to 3,4-dihydro-2H,6H-pyrimido[2,1-b][1,3]thiazines 8a-c, 8a′-c′ and thiazolo[3,2-b]pyrimidines 9a,b, 9a′,b′, 10a,b took place.
Arjan W. Kleij - One of the best experts on this subject based on the ideXlab platform.
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highly chemoselective catalytic coupling of substituted oxetanes and carbon dioxide
Chemistry: A European Journal, 2015Co-Authors: Jeroen Rintjema, Eduardo C Escuderoadan, Eddy Martin, Arjan W. KleijAbstract:The chemoselective coupling of oxetanes and carbon dioxide to afford functional, heterocyclic organic compounds known as six-membered cyclic carbonates remains a challenging topic. Here, an effective method for their synthesis relying on the use of Al catalysis is described. The catalytic reactions can be carried out with excellent selectivity for the cyclic carbonate product tolerating various (functional) groups present in the 2- and 3-position(s) of the oxetane ring. The presented methodology is the first general approach towards the formation of six-membered cyclic carbonates (6MCCs) through oxetane/CO2 coupling chemistry. Apart from a series of substituted six-membered cyclic carbonates, also the unprecedented room-temperature coupling of oxetanes and CO2 is disclosed giving, depending on the structural features of the substrate, a variety of five- and six-membered heterocyclic products. A mechanistic rationale is presented for their formation and support for the intermediary presence of a Carbonic Acid Derivative is given. The presented functional carbonates may hold great promise as building blocks in organic synthesis and the development of new, biodegradable polymers.