A series of proline-based amino pyridine dipeptide organocatalysts was synthesized and applied in direct asymmetric intermolecular aldol reaction. These catalysts showed good solubility in organic solvents, good yield...A series of proline-based amino pyridine dipeptide organocatalysts was synthesized and applied in direct asymmetric intermolecular aldol reaction. These catalysts showed good solubility in organic solvents, good yields (73%―97%) and enantioselectivitives(74%―94%). Among them, dipeptide organocatalyst(2) was found to be the most efficient one for the asymmetric aldol reaction between cyclohexanone and 4-nitrobeznaldehyde. After optimizing the catalytic reaction conditions, we found that the catalyst showed high yield(97%), enantioselectivity(e.e., up to 92%) and anti-diastereoselectivity(up to 95:5) at mild room temperature without any additives.展开更多
Thirteen novel phenoxysulfonylureas derivatives were synthesized, and their structures were confirmed by MS, NMR and element analysis. The herbicidal activity and structure-activity relationship were also investigated...Thirteen novel phenoxysulfonylureas derivatives were synthesized, and their structures were confirmed by MS, NMR and element analysis. The herbicidal activity and structure-activity relationship were also investigated. The results of preliminary active tests indicate that the compounds show moderate herbicidal activity.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.20802025 and 20082011)
文摘A series of proline-based amino pyridine dipeptide organocatalysts was synthesized and applied in direct asymmetric intermolecular aldol reaction. These catalysts showed good solubility in organic solvents, good yields (73%―97%) and enantioselectivitives(74%―94%). Among them, dipeptide organocatalyst(2) was found to be the most efficient one for the asymmetric aldol reaction between cyclohexanone and 4-nitrobeznaldehyde. After optimizing the catalytic reaction conditions, we found that the catalyst showed high yield(97%), enantioselectivity(e.e., up to 92%) and anti-diastereoselectivity(up to 95:5) at mild room temperature without any additives.
基金Supported by the National Natural Science Foundation of China(Nos.20802025 and 20082011)
文摘Thirteen novel phenoxysulfonylureas derivatives were synthesized, and their structures were confirmed by MS, NMR and element analysis. The herbicidal activity and structure-activity relationship were also investigated. The results of preliminary active tests indicate that the compounds show moderate herbicidal activity.