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In recent years, a small ring nitrogen organic catalyst due to its easily available raw materials , synthetic method is simple , environmentally friendly, and has been extensively studied . How to design, synthesize with high activity and high selectivity azacyclic Organocatalyst has become a hot research . An aza three . Tetracyclic silyl ether synthesis catalyst from trityl aza three , four-membered ring methyl departure , after three steps successfully synthesized a novel heterocyclic silyl ether catalyst . Underlying structure of the product through 1H NMR, 13C NMR spectroscopy, mass spectrometry , infrared and other means were characterized . Two asymmetric Michael addition reaction of aliphatic aldehydes with the catalyst for all kinds of asymmetric Michael addition of nitro- olefins reaction , the system examines the reaction solvent , temperature, time and other factors . 0.25 mmol and 2.5 mmol of nitro- ene aldehyde at 0 ℃ or 28 ℃ under anhydrous acetonitrile as solvent, with 10 mol% or 20 mol% times the amount of catalyst, the reaction 48 h, up to 98% for maximum ee values. 3 Reaction of hydroxylamine this asymmetric catalysts are also used for various aldehydes with α- hydroxylamine Nitrosobenzene the reaction , 1 mmol alkylene nitrobenzene and 3 mmol of aldehyde at 0 ℃ under anhydrous dichloro methane as solvent, times the amount of 20 mol% catalyst, 1-2 h, to obtain the value of up to 85% ee .
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