A highly active catalyst for the reductive cyclization of ortho-nitrostyrenes under mild conditions
摘要:
A mild and efficient method for the palladium-Catalyzed reductive Cyclization of ortho-nitrostyrenes to afford indoles is reported. \Treatment of ortho-nitrostyrenes with 0.1 mol% palladium (II) trifluoracetate [Pd(TFA)(2)] and 0.7 mol% 3.4,7,8-tetramethyl-1,10-phenanthroline (tm-phen) in DMF at 15 psig CO and 80 degrees C afforded indoles in good to excellent yields. When the reaction was conducted in toluene. the corresponding N-hydroxyindole was isolated. A mechanism that accounts for the formation of N-hydroxyindole is proposed. (c) 2005 Elsevier Ltd. All rights reserved.
A highly active catalyst for the reductive cyclization of ortho-nitrostyrenes under mild conditions
摘要:
A mild and efficient method for the palladium-Catalyzed reductive Cyclization of ortho-nitrostyrenes to afford indoles is reported. \Treatment of ortho-nitrostyrenes with 0.1 mol% palladium (II) trifluoracetate [Pd(TFA)(2)] and 0.7 mol% 3.4,7,8-tetramethyl-1,10-phenanthroline (tm-phen) in DMF at 15 psig CO and 80 degrees C afforded indoles in good to excellent yields. When the reaction was conducted in toluene. the corresponding N-hydroxyindole was isolated. A mechanism that accounts for the formation of N-hydroxyindole is proposed. (c) 2005 Elsevier Ltd. All rights reserved.
Synthesis of Novel KDR Kinase Inhibitors through Catalytic Reductive Cyclization of <i>o</i>-Nitrobenzylcarbonyl Compounds
作者:Audrey Wong、Jeffrey T. Kuethe、Ian W. Davies、David L. Hughes
DOI:10.1021/jo048843m
日期:2004.10.1
through the Swern-type oxidation of readily accessible phenethanol analogues. Reductive cyclization of o-nitrobenzylcarbonyl 3 using catalytic Raneynickel gives 1H-indol-2-yl-1H-quinoline 2 in 95% yield. Hydrolysis of 2 affords the KDR kinase inhibitor 1 in quantitative yield. The examination of the reductive cyclization reaction and optimization of conditions is described.
Synthesis of 5-Substituted-1<i>H</i>-indol-2-yl-1<i>H</i>-quinolin-2-ones: A Novel Class of KDR Kinase Inhibitors
作者:Jeffrey T. Kuethe、Audrey Wong、Chuanxing Qu、Jacqueline Smitrovich、Ian W. Davies、David L. Hughes
DOI:10.1021/jo0480545
日期:2005.4.1
A number of approaches for the synthesis of the 1H-indol-2-yl-1H-quinolin-2-one ring system found in the potent and selective KDR kinase inhibitor 1 are described. The preparation and reaction of trimethylsilylnitrobenzene 26 with 2-methoxy-3-quinolinecarboxaldehyde 28 afforded alcohol 30, which was the key intermediate for the preparation of the target compounds. Conversion of alcohol 30 to either nitroketone 36 or nitrostyrene 45 set the stage for reductive cyclization and the formation of indole 25. The quinolin-2-one functionality was unmasked in the last step to provide compound 1 in 56-60% overall yield from readily available starting materials.
A highly active catalyst for the reductive cyclization of ortho-nitrostyrenes under mild conditions
作者:Ian W. Davies、Jacqueline H. Smitrovich、Rick Sidler、Chuanxing Qu、Venita Gresham、Charles Bazaral
DOI:10.1016/j.tet.2005.03.142
日期:2005.6
A mild and efficient method for the palladium-Catalyzed reductive Cyclization of ortho-nitrostyrenes to afford indoles is reported. \Treatment of ortho-nitrostyrenes with 0.1 mol% palladium (II) trifluoracetate [Pd(TFA)(2)] and 0.7 mol% 3.4,7,8-tetramethyl-1,10-phenanthroline (tm-phen) in DMF at 15 psig CO and 80 degrees C afforded indoles in good to excellent yields. When the reaction was conducted in toluene. the corresponding N-hydroxyindole was isolated. A mechanism that accounts for the formation of N-hydroxyindole is proposed. (c) 2005 Elsevier Ltd. All rights reserved.