Lewis Acid-Directed Cyclocondensation of Piperidone Enol Ethers with 2-Methoxy-4-(N-phenylsulfonyl)-1,4-benzoquinoneimine: A New Regioselective Synthesis of Oxygenated Carbolines
摘要:
Lewis acid-directed cyclocondensations of piperidone enol ethers with 2-methoxy-4-(N-phenylsulfonyl)-1,4-benzoquinoneimine are reported. Benzofurans are obtained with BF3. OEt2 as a promoter, whereas use of excess amounts of TiCl4:Ti(OiPr)(4) leads to tetrahydrocarbolines. The latter reactions provide expedient routes to oxygen-substituted tetrahydrocarbolines and carbolines. As applications of this new methodology, the preparations of 1-[3-(dimethylamino)propyl] amino-7-methoxy- and 1-[3-(dimethylamino)propyl]amino-7,8-dimethoxy-5H-pyrido[4,3-b]indoles are described.
Lewis Acid-Directed Cyclocondensation of Piperidone Enol Ethers with 2-Methoxy-4-(N-phenylsulfonyl)-1,4-benzoquinoneimine: A New Regioselective Synthesis of Oxygenated Carbolines
摘要:
Lewis acid-directed cyclocondensations of piperidone enol ethers with 2-methoxy-4-(N-phenylsulfonyl)-1,4-benzoquinoneimine are reported. Benzofurans are obtained with BF3. OEt2 as a promoter, whereas use of excess amounts of TiCl4:Ti(OiPr)(4) leads to tetrahydrocarbolines. The latter reactions provide expedient routes to oxygen-substituted tetrahydrocarbolines and carbolines. As applications of this new methodology, the preparations of 1-[3-(dimethylamino)propyl] amino-7-methoxy- and 1-[3-(dimethylamino)propyl]amino-7,8-dimethoxy-5H-pyrido[4,3-b]indoles are described.
Lewis Acid-Directed Cyclocondensation of Piperidone Enol Ethers with 2-Methoxy-4-(<i>N</i>-phenylsulfonyl)-1,4-benzoquinoneimine: A New Regioselective Synthesis of Oxygenated Carbolines
作者:Thomas A. Engler、Jutta Wanner
DOI:10.1021/jo9916176
日期:2000.4.1
Lewis acid-directed cyclocondensations of piperidone enol ethers with 2-methoxy-4-(N-phenylsulfonyl)-1,4-benzoquinoneimine are reported. Benzofurans are obtained with BF3. OEt2 as a promoter, whereas use of excess amounts of TiCl4:Ti(OiPr)(4) leads to tetrahydrocarbolines. The latter reactions provide expedient routes to oxygen-substituted tetrahydrocarbolines and carbolines. As applications of this new methodology, the preparations of 1-[3-(dimethylamino)propyl] amino-7-methoxy- and 1-[3-(dimethylamino)propyl]amino-7,8-dimethoxy-5H-pyrido[4,3-b]indoles are described.