The Experts below are selected from a list of 135 Experts worldwide ranked by ideXlab platform
Gangajji Parameshwarappa - One of the best experts on this subject based on the ideXlab platform.
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one pot synthesis of 2 4 5 trisubstituted imidazoles via 2 2 1 cycloannulation of 1 3 bishet aryl monothio 1 3 diketones α substituted methylamines and sodium nitrite through α nitrosation of enaminones
Journal of Organic Chemistry, 2016Co-Authors: Somaraju Yugandar, Saidulu Konda, Gangajji ParameshwarappaAbstract:An efficient one-pot synthesis of a series of diversely functionalized trisubstituted 4(5)het(aroyl)-2,5(4)-het(aryl)/alkylimidazoles from readily available 1,3-bishet(aryl)monothio-1,3-diketones has been reported. This novel sequential one-pot, three step protocol, wherein three new carbon nitrogen bonds are formed in contiguous fashion, involves in situ generation of enaminones by reaction of monothio-1,3-diketones with α-substituted methylamines, followed by their α-nitrosation with sodium nitrite and subsequent base mediated Intramolecular Heterocyclization of the resulting α-hydroxyiminoimines to trisubstituted imidazoles in high yields under mild conditions. These newly prepared 4(5)-het(aroyl)-5(4)-het(aryl)/alkylimidazoles are shown to exist as tautomeric mixture, however, their subsequent alkylation with methyl iodide in the presence of potassium carbonate affords 1-N-methy-2,5-bishet(aryl)-4-het(aroyl)imidazoles in highly regioselective fashion in most of the cases. Synthesis of few 4(5)-(2-hydr...
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One-Pot Synthesis of 2,4,5-Trisubstituted Imidazoles via [2 + 2 + 1] Cycloannulation of 1,3-Bishet(aryl)-monothio-1,3-diketones, α‑Substituted Methylamines and Sodium Nitrite through α‑Nitrosation of Enaminones
2016Co-Authors: Somaraju Yugandar, Saidulu Konda, Gangajji Parameshwarappa, H. IlaAbstract:An efficient one-pot synthesis of a series of diversely functionalized trisubstituted 4(5)het(aroyl)-2,5(4)-het(aryl)/alkylimidazoles from readily available 1,3-bishet(aryl)monothio-1,3-diketones has been reported. This novel sequential one-pot, three step protocol, wherein three new carbon nitrogen bonds are formed in contiguous fashion, involves in situ generation of enaminones by reaction of monothio-1,3-diketones with α-substituted methylamines, followed by their α-nitrosation with sodium nitrite and subsequent base mediated Intramolecular Heterocyclization of the resulting α-hydroxyiminoimines to trisubstituted imidazoles in high yields under mild conditions. These newly prepared 4(5)-het(aroyl)-5(4)-het(aryl)/alkylimidazoles are shown to exist as tautomeric mixture, however, their subsequent alkylation with methyl iodide in the presence of potassium carbonate affords 1-N-methy-2,5-bishet(aryl)-4-het(aroyl)imidazoles in highly regioselective fashion in most of the cases. Synthesis of few 4(5)-(2-hydroxyphenyl)-2,5(4)-substituted imidazoles, which are known to be good coordinating ligands, has also been reported. A probable mechanism for the formation of these imidazoles from hydroxyiminoimine intermediates has also been suggested
Somaraju Yugandar - One of the best experts on this subject based on the ideXlab platform.
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one pot synthesis of 2 4 5 trisubstituted imidazoles via 2 2 1 cycloannulation of 1 3 bishet aryl monothio 1 3 diketones α substituted methylamines and sodium nitrite through α nitrosation of enaminones
Journal of Organic Chemistry, 2016Co-Authors: Somaraju Yugandar, Saidulu Konda, Gangajji ParameshwarappaAbstract:An efficient one-pot synthesis of a series of diversely functionalized trisubstituted 4(5)het(aroyl)-2,5(4)-het(aryl)/alkylimidazoles from readily available 1,3-bishet(aryl)monothio-1,3-diketones has been reported. This novel sequential one-pot, three step protocol, wherein three new carbon nitrogen bonds are formed in contiguous fashion, involves in situ generation of enaminones by reaction of monothio-1,3-diketones with α-substituted methylamines, followed by their α-nitrosation with sodium nitrite and subsequent base mediated Intramolecular Heterocyclization of the resulting α-hydroxyiminoimines to trisubstituted imidazoles in high yields under mild conditions. These newly prepared 4(5)-het(aroyl)-5(4)-het(aryl)/alkylimidazoles are shown to exist as tautomeric mixture, however, their subsequent alkylation with methyl iodide in the presence of potassium carbonate affords 1-N-methy-2,5-bishet(aryl)-4-het(aroyl)imidazoles in highly regioselective fashion in most of the cases. Synthesis of few 4(5)-(2-hydr...
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One-Pot Synthesis of 2,4,5-Trisubstituted Imidazoles via [2 + 2 + 1] Cycloannulation of 1,3-Bishet(aryl)-monothio-1,3-diketones, α‑Substituted Methylamines and Sodium Nitrite through α‑Nitrosation of Enaminones
2016Co-Authors: Somaraju Yugandar, Saidulu Konda, Gangajji Parameshwarappa, H. IlaAbstract:An efficient one-pot synthesis of a series of diversely functionalized trisubstituted 4(5)het(aroyl)-2,5(4)-het(aryl)/alkylimidazoles from readily available 1,3-bishet(aryl)monothio-1,3-diketones has been reported. This novel sequential one-pot, three step protocol, wherein three new carbon nitrogen bonds are formed in contiguous fashion, involves in situ generation of enaminones by reaction of monothio-1,3-diketones with α-substituted methylamines, followed by their α-nitrosation with sodium nitrite and subsequent base mediated Intramolecular Heterocyclization of the resulting α-hydroxyiminoimines to trisubstituted imidazoles in high yields under mild conditions. These newly prepared 4(5)-het(aroyl)-5(4)-het(aryl)/alkylimidazoles are shown to exist as tautomeric mixture, however, their subsequent alkylation with methyl iodide in the presence of potassium carbonate affords 1-N-methy-2,5-bishet(aryl)-4-het(aroyl)imidazoles in highly regioselective fashion in most of the cases. Synthesis of few 4(5)-(2-hydroxyphenyl)-2,5(4)-substituted imidazoles, which are known to be good coordinating ligands, has also been reported. A probable mechanism for the formation of these imidazoles from hydroxyiminoimine intermediates has also been suggested
Saidulu Konda - One of the best experts on this subject based on the ideXlab platform.
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one pot synthesis of 2 4 5 trisubstituted imidazoles via 2 2 1 cycloannulation of 1 3 bishet aryl monothio 1 3 diketones α substituted methylamines and sodium nitrite through α nitrosation of enaminones
Journal of Organic Chemistry, 2016Co-Authors: Somaraju Yugandar, Saidulu Konda, Gangajji ParameshwarappaAbstract:An efficient one-pot synthesis of a series of diversely functionalized trisubstituted 4(5)het(aroyl)-2,5(4)-het(aryl)/alkylimidazoles from readily available 1,3-bishet(aryl)monothio-1,3-diketones has been reported. This novel sequential one-pot, three step protocol, wherein three new carbon nitrogen bonds are formed in contiguous fashion, involves in situ generation of enaminones by reaction of monothio-1,3-diketones with α-substituted methylamines, followed by their α-nitrosation with sodium nitrite and subsequent base mediated Intramolecular Heterocyclization of the resulting α-hydroxyiminoimines to trisubstituted imidazoles in high yields under mild conditions. These newly prepared 4(5)-het(aroyl)-5(4)-het(aryl)/alkylimidazoles are shown to exist as tautomeric mixture, however, their subsequent alkylation with methyl iodide in the presence of potassium carbonate affords 1-N-methy-2,5-bishet(aryl)-4-het(aroyl)imidazoles in highly regioselective fashion in most of the cases. Synthesis of few 4(5)-(2-hydr...
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One-Pot Synthesis of 2,4,5-Trisubstituted Imidazoles via [2 + 2 + 1] Cycloannulation of 1,3-Bishet(aryl)-monothio-1,3-diketones, α‑Substituted Methylamines and Sodium Nitrite through α‑Nitrosation of Enaminones
2016Co-Authors: Somaraju Yugandar, Saidulu Konda, Gangajji Parameshwarappa, H. IlaAbstract:An efficient one-pot synthesis of a series of diversely functionalized trisubstituted 4(5)het(aroyl)-2,5(4)-het(aryl)/alkylimidazoles from readily available 1,3-bishet(aryl)monothio-1,3-diketones has been reported. This novel sequential one-pot, three step protocol, wherein three new carbon nitrogen bonds are formed in contiguous fashion, involves in situ generation of enaminones by reaction of monothio-1,3-diketones with α-substituted methylamines, followed by their α-nitrosation with sodium nitrite and subsequent base mediated Intramolecular Heterocyclization of the resulting α-hydroxyiminoimines to trisubstituted imidazoles in high yields under mild conditions. These newly prepared 4(5)-het(aroyl)-5(4)-het(aryl)/alkylimidazoles are shown to exist as tautomeric mixture, however, their subsequent alkylation with methyl iodide in the presence of potassium carbonate affords 1-N-methy-2,5-bishet(aryl)-4-het(aroyl)imidazoles in highly regioselective fashion in most of the cases. Synthesis of few 4(5)-(2-hydroxyphenyl)-2,5(4)-substituted imidazoles, which are known to be good coordinating ligands, has also been reported. A probable mechanism for the formation of these imidazoles from hydroxyiminoimine intermediates has also been suggested
Xiangying Tang - One of the best experts on this subject based on the ideXlab platform.
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gold i catalyzed selective Heterocyclization of propargylic thioureas mechanistic study of competitive gold activation mode
ChemInform, 2015Co-Authors: Yu Jiang, Xiangying TangAbstract:A new selective gold(I)-catalyzed Intramolecular Heterocyclization of homopropargylic isothiocyanates, erroneously named propargylic thioureas, is developed, efficiently affording two kinds of cycloadducts in moderate to excellent yields with a broad substrate scope.
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gold i catalyzed selective Heterocyclization of propargylic thioureas mechanistic study of competitive gold activation mode
Chemistry: A European Journal, 2015Co-Authors: Yu Jiang, Xiangying TangAbstract:A new selective gold(I)-catalyzed Intramolecular Heterocyclization of propargylic thioureas has been developed, efficiently affording two kinds of cycloadducts in moderate to excellent yields with a broad substrate scope. Further mechanistic investigations indicate that competitive different gold activation modes feature in these cyclization processes. Kinetic experiments reveal that the gold activation mode is influenced by the ligand of the gold catalyst and the reaction conditions.
Metin Balci - One of the best experts on this subject based on the ideXlab platform.
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Intramolecular Heterocyclization of o propargylated aromatic hydroxyaldehydes as an expedient route to substituted chromenopyridines under metal free conditions
ChemInform, 2015Co-Authors: Selbi Keskin, Metin BalciAbstract:Chromenopyridines are prepared regioselectively in two steps by O—propargylation of aromatic hydroxyaldehydes followed by Intramolecular Heterocyclization with propargylamine.
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Intramolecular Heterocyclization of O-Propargylated Aromatic Hydroxyaldehydes as an Expedient Route to Substituted Chromenopyridines under Metal-Free Conditions
Organic letters, 2015Co-Authors: Selbi Keskin, Metin BalciAbstract:A concise and regioselective approach to the synthesis of chromenopyridine and chromenopyridinone derivatives was developed. The synthetic strategy relies on the O-propargylation of aromatic hydroxyaldehydes followed by reaction with propargylamine. The Intramolecular cycloaddition reaction between the alkyne and azadiene, which is formed as an intermediate, furnished the desired skeletons.