Thermocontrolled benzylimine–benzaldimine rearrangement over Nafion-H catalysts for efficient entry into α-trifluoromethylbenzylamines
摘要:
Nation-H and Nation SAC-13 are efficient solid Bronsted acid catalysts for the preparation of trifluoromethyl ketimines from benzylamines and trifluoromethylated ketones in high yields. A finely tuned benzylimine-benzaldimine rearrangement by facile 1,3-hydrogen shift has been achieved for the formation of fluorinated benzaldimines in high yields by careful optimization of reaction conditions including attempts under microwave conditions and a flow system. These alpha-trifluoromethylated benzaldimines are efficient precursors for pharmaceutically important alpha-trifluoromethylated benzylamines, accessed through their direct acid hydrolysis. (C) 2011 Elsevier Ltd. All rights reserved.
The ruthenium-catalyzed asymmetric reductiveamination of aryl-trifluoromethyl ketones affording high value primary α-(trifluoromethyl)arylmethylamines using cheap NH4OAc as the nitrogen source and H2 as the reductant is reported. This user-friendly and simple catalytic method tolerates various aromatic functions with electron-withdrawing or -donating substituents at the para- or meta-positions and
Thermocontrolled benzylimine–benzaldimine rearrangement over Nafion-H catalysts for efficient entry into α-trifluoromethylbenzylamines
作者:G.K. Surya Prakash、Kevin E. Glinton、Chiradeep Panja、Laxman Gurung、Patrice T. Battamack、Béla Török、Thomas Mathew、George A. Olah
DOI:10.1016/j.tetlet.2011.11.088
日期:2012.2
Nation-H and Nation SAC-13 are efficient solid Bronsted acid catalysts for the preparation of trifluoromethyl ketimines from benzylamines and trifluoromethylated ketones in high yields. A finely tuned benzylimine-benzaldimine rearrangement by facile 1,3-hydrogen shift has been achieved for the formation of fluorinated benzaldimines in high yields by careful optimization of reaction conditions including attempts under microwave conditions and a flow system. These alpha-trifluoromethylated benzaldimines are efficient precursors for pharmaceutically important alpha-trifluoromethylated benzylamines, accessed through their direct acid hydrolysis. (C) 2011 Elsevier Ltd. All rights reserved.
Catalytic Asymmetric Synthesis of α-Tetrasubstituted α-Trifluoromethyl Homoallylic Amines by Ir-Catalyzed Umpolung Allylation of Imines
作者:Yingwei Wang、Li-Fan Deng、Xia Zhang、Dawen Niu
DOI:10.1021/acs.orglett.9b02550
日期:2019.9.6
homoallylic amines is established. This reaction, which involves an Ir-catalyzed umpolung allylation of imines and a 2-aza-Cope rearrangement cascade, could yield both tetrasubstituted and trisubstituted stereocenters. This transformation employs readily available starting materials and displays broad substrate scope. The isolation and structural determination of reaction intermediates revealed factors critical