Synthesis of 5-alkyl-5-aryl-γ-lactams from 1-aryl-substituted nitroalkanes and methyl acrylate via Michael addition and reductive lactamization
摘要:
A general method for accessing 5-alkyl-5-aryl-gamma-lactams has been developed using readily available aryl bromides, nitroalkanes, and methyl acrylate as the starting materials. The palladium-catalyzed arylation of nitroalkanes gave the 1-aryl-substituted nitroalkanes, which underwent the DBU-mediated Michael addition with methyl acrylate at room temperature to afford the methyl 4-aryl-4-nitroalkanoates. The latter were then subjected to the nitro reduction using NaBH4-NiCl2 center dot 6H(2)O in MeOH at 0 degrees C to furnish, after treatment with aqueous K2CO3 at room temperature, the 5-alkyl-5-aryl-gamma-lactams in good to excellent overall yields. Selected examples of N-alkylation of the gamma-lactams were also illustrated. (C) 2014 Elsevier Ltd. All rights reserved.
Aryl ketones were prepared from aryl triflates and nitroalkanes through a palladium-catalyzedcross-coupling followed by Nef-type reaction in a one-pot synthesis.
芳基酮是由芳基三氟甲磺酸酯和硝基烷烃通过钯催化的交叉偶联然后在一锅合成中的 Nef 型反应制备的。
Synthesis of 5-alkyl-5-aryl-1-pyrroline N-oxides from 1-aryl-substituted nitroalkanes and acrolein via Michael addition and nitro reductive cyclization
作者:Jingjing Xu、Xingyao Li、Jinlong Wu、Wei-Min Dai
DOI:10.1016/j.tet.2014.07.046
日期:2014.9
A general method for accessing 5-alkyl-5-aryl-1-pyrroline N-oxides (AAPOs) has been established using readily available aryl bromides, nitroalkanes, and acrolein as the starting materials. The palladium-catalyzed arylation of nitroalkanes gave the 1-aryl-substituted nitroalkanes, which underwent the Et3N-catalyzed Michael addition with acrolein at room temperature to afford the 4-aryl-4-nitroaldehydes
Synthesis of 5-alkyl-5-aryl-γ-lactams from 1-aryl-substituted nitroalkanes and methyl acrylate via Michael addition and reductive lactamization
作者:Jingjing Xu、Xingyao Li、Jinlong Wu、Wei-Min Dai
DOI:10.1016/j.tet.2014.04.074
日期:2014.6
A general method for accessing 5-alkyl-5-aryl-gamma-lactams has been developed using readily available aryl bromides, nitroalkanes, and methyl acrylate as the starting materials. The palladium-catalyzed arylation of nitroalkanes gave the 1-aryl-substituted nitroalkanes, which underwent the DBU-mediated Michael addition with methyl acrylate at room temperature to afford the methyl 4-aryl-4-nitroalkanoates. The latter were then subjected to the nitro reduction using NaBH4-NiCl2 center dot 6H(2)O in MeOH at 0 degrees C to furnish, after treatment with aqueous K2CO3 at room temperature, the 5-alkyl-5-aryl-gamma-lactams in good to excellent overall yields. Selected examples of N-alkylation of the gamma-lactams were also illustrated. (C) 2014 Elsevier Ltd. All rights reserved.