Asymmetric synthesis of piperidines using the nitro-Mannich reaction☆
نویسندگان
چکیده
Abstract A method for the synthesis of functionalized piperidines containing 3 contiguous stereocentres in 2-,3- and 4- positions uses a diastereoselective nitro-Mannich to control stereochemistry. The reaction between β-aryl/heteroaryl substituted nitroalkanes glyoxylate imine provides β-nitro-amines with good selectivity (70:30 >95:5) syn, anti-diastereoisomers. Reductive cyclisation BF3.OEt2 Et3SiH gave, after purification, stereochemically pure 19–57% yield ten examples different 4-aryl/heteroaryl substituents.
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ژورنال
عنوان ژورنال: Tetrahedron
سال: 2021
ISSN: ['0040-4020', '1464-5416']
DOI: https://doi.org/10.1016/j.tet.2020.131821