On January 31, 2022, Kozma, Viktoria; Szollosi, Gyorgy published an article.Category: esters-buliding-blocks The title of the article was Conjugate addition of 1,3-dicarbonyl compounds to maleimides using bifunctional primary amine-(thio)phosphoramide organocatalysts. And the article contained the following:
Asym. Michael additions of 1,3-dicarbonyl compounds to N-substituted maleimides were carried out using primary amine-(thio)phosphoramide bifunctional chiral organocatalysts derived from optically pure C2-sym. 1,2-diamines. The addition of Et 2-fluoroacetoacetate using the 1,2-diphenylethane-1,2-diamine derived thiophosphoramide catalyst afforded various succinimides substituted with fluorine bearing quaternary carbon in high yields, good diastereomeric ratios and excellent enantiomeric excesses. Alicyclic β-ketoesters provided the diastereomerically pure Michael adducts in good yields and high enantioselectivities, whereas 2,4-pentanedione afforded products with slightly lower enantiomeric excesses. The bulkiness of the N-substituent of the maleimide ring influenced mostly the conversions. The thiophosphoramide catalyst was found also efficient in the addition of Et 2-fluoroacetoacetate to β-nitrostyrenes. Unprecedentedly, during this work the highly enantioselective addition of 1,3-dicarbonyl compounds to maleimides were catalyzed by a primary amine-hydrogen-bond donor groups containing bifunctional organocatalyst. These reactions occurred through enamine intermediate, as evidenced by electrospray-ionization mass spectrometry and NMR spectroscopy. The experimental process involved the reaction of Methyl 2-cyclopentanonecarboxylate(cas: 10472-24-9).Category: esters-buliding-blocks
The Article related to maleimide dicarbonyl compound stereoselective conjugate addition, primary amine thio phosphoramide organocatalyst, Heterocyclic Compounds (One Hetero Atom): Pyrroles and Pyrrolizines and other aspects.Category: esters-buliding-blocks
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