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硝基化合物的不对称迈克尔加成反应 总被引:1,自引:0,他引:1
从以下三方面对硝基化合物的不对称迈克尔加成反应进行了较为详细的综述: (1)手性催化剂催化的迈克尔加成,(2)共轭硝基物与手性亲核试剂的迈克加成 ,(3)脂肪族硝基物对手性迈克加成受体的迈克尔加成。 相似文献
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Michael addition on 2H-1,4-benzothiazin-3-ones is studied in this communication. An approach towards the regioselective synthesis of Michael adducts is shown. 相似文献
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A facile triphenylphosphine-catalyzed Michael addition of alcohols to acrylic compounds was described. The reaction was carried out in open air at refluxing temperature in the presence of 10 mol% PPh3. Michael addition of saturated and unsaturated alcohols to acrylonitrile or acrylates has been examined. The reaction gave β-alkoxy derivatives with isolated yields of 5%-79%. PPh3 is cheaper and more stable than those trialkylphosphines previously used for the similar reactions, and the products can be easily separated from the reaction mixture via distillation. 相似文献
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Enantioselective Desymmetrization of Prochiral Cyclohexanones by Organocatalytic Intramolecular Michael Additions to α,β‐Unsaturated Esters 下载免费PDF全文
Adam D. Gammack Yamagata Dr. Swarup Datta Kelvin E. Jackson Linus Stegbauer Dr. Robert S. Paton Prof. Dr. Darren J. Dixon 《Angewandte Chemie (International ed. in English)》2015,54(16):4899-4903
A new catalytic asymmetric desymmetrization reaction for the synthesis of enantioenriched derivatives of 2‐azabicyclo[3.3.1]nonane, a key motif common to many alkaloids, has been developed. Employing a cyclohexanediamine‐derived primary amine organocatalyst, a range of prochiral cyclohexanone derivatives possessing an α,β‐unsaturated ester moiety linked to the 4‐position afforded the bicyclic products, which possess three stereogenic centers, as single diastereoisomers in high enantioselectivity (83–99 % ee) and in good yields (60–90 %). Calculations revealed that stepwise C? C bond formation and proton transfer via a chair‐shaped transition state dictate the exclusive endo selectivity and enabled the development of a highly enantioselective primary amine catalyst. 相似文献
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Araceli Zárate Laura Orea Jorge R. Juárez Alejandro Castro Angel Mendoza Dino Gnecco 《合成通讯》2014,44(19):2838-2847
A synthetic route for the access to enantiopure cis-4-methyl/thiol-pipecolic esters is presented. It is based on the ring-closing metathesis reaction to build the α,β-unsaturated piperidin-2-one derived from (S)-(–)-phenylethylamine, followed by either diastereoselective conjugate addition of methylorganocuprate allowing access to cis-4-methyl pipecolic ester or by tandem diastereoselective hydrosulforization–thionization reaction providing access to cis-4-thiol pipecolic ethyl esters. 相似文献
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Nucleophilic phosphorus add to tetraethyl ethylidene diphosphonate in protic solvent to yield the product of the Michael reaction. This reaction appeared to be reversible at a temperature upper than 160 °C. To avoid this reverse reaction, alkylation in α position of the two phosphonate functions by activated elecrophile is reported. 相似文献