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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.

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. The latter were then subjected to the nitro reductive cyclization using Zn-HOAc in EtOH at 0 degrees C followed by warming the reaction mixture to room temperature for 24 h, furnishing the 5alky1-5-ary1-1-pyrroline N-oxides in good overall yields. Selected examples of 1,3-dipolar cycloaddition of the cyclic nitrones with methyl methacrylate were also described. (C) 2014 Elsevier Ltd. All rights reserved.

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. The latter were then subjected to the nitro reductive cyclization using Zn-HOAc in EtOH at 0 degrees C followed by warming the reaction mixture to room temperature for 24 h, furnishing the 5alky1-5-ary1-1-pyrroline N-oxides in good overall yields. Selected examples of 1,3-dipolar cycloaddition of the cyclic nitrones with methyl methacrylate were also described. (C) 2014 Elsevier Ltd. All rights reserved.

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.

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. The latter were then subjected to the nitro reductive cyclization using Zn-HOAc in EtOH at 0 degrees C followed by warming the reaction mixture to room temperature for 24 h, furnishing the 5alky1-5-ary1-1-pyrroline N-oxides in good overall yields. Selected examples of 1,3-dipolar cycloaddition of the cyclic nitrones with methyl methacrylate were also described. (C) 2014 Elsevier Ltd. All rights reserved.

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.