Asymmetric Conjugate Additions of Chiral Phosphonamide Anions to α,β-Unsaturated Carbonyl Compounds. A Versatile Method for Vicinally Substituted Chirons
作者:Stephen Hanessian、Arthur Gomtsyan、Nadia Malek
DOI:10.1021/jo000388g
日期:2000.9.1
Reactions of anions derived from chiral nonracemic allyl, crotyl, and cinnamyl bicyclic C(2)-symmetrical phosphonamides with alpha, beta-unsaturated cyclic ketones, esters, lactones, and lactams take place at the gamma-position of the reagents. The products are diastereomerically pure or enriched beta-substituted carbonylcompounds. The method also provides easy access to vicinal substitution of as
Allyl-Nickel Catalysis Enables Carbonyl Dehydrogenation and Oxidative Cycloalkenylation of Ketones
作者:David Huang、Suzanne M. Szewczyk、Pengpeng Zhang、Timothy R. Newhouse
DOI:10.1021/jacs.9b02552
日期:2019.4.10
of carbonyl compounds using allyl-nickel catalysis. This development overcomes several limitations of previously reported allyl-palladium-catalyzed oxidation, and is further leveraged for the development of an oxidative cycloalkenylation reaction that provides access to bicycloalkenones with fused, bridged, and spirocyclic ring systems using unactivated ketone and alkene precursors.
A regioselective diels-alder synthesis of ellipticine
作者:Deborah A. Davis、Gordon W. Gribble
DOI:10.1016/s0040-4039(00)88731-6
日期:——
4-b]indole (3) and 5,6-dihydropyridones (10) shows high regioselectivity, yielding carbazole 11 upon hydrolytic workup. Carbazole 11b has been successfully converted to the pyridocarbazole alkaloid ellipticine (1).
Carbocyclic Amino Ketones by Bredt's Rule‐Arrested Kulinkovich–de Meijere Reaction
作者:Paul B. Finn、Brenden P. Derstine、Scott McN. Sieburth
DOI:10.1002/anie.201509983
日期:2016.2.12
reaction, involves two carbon–carbon bond‐forming steps. Strategic use of a tricyclic intermediate can arrest the process if the second step requires formation of a bridgehead double bond. Use of this Bredt'srule constraint results in the production of carbocyclic amino ketones, key alkaloid building blocks.
Ti II介导的由烯烃和酰胺形成的环丙胺,Kulinkovich-de Meijere反应涉及两个碳-碳键形成步骤。如果第二步需要形成桥头双键,则三环中间体的战略性使用可中止该过程。使用此Bredt规则约束会产生碳环氨基酮(关键生物碱构件)的产生。
Palladium-catalyzed β-(hetero)arylation of α,β-unsaturated valerolactams
作者:Daniel P. Canterbury、Kevin D. Hesp、Jana Polivkova
DOI:10.1039/c6ob01126h
日期:——
A method for the palladium-catalyzed arylation of α,β-unsaturated valerolactams is reported. This new protocol provides arylation products in yields up to 95% and is applicable to a wide array of aryl and heteroaryl bromides. The optimization, scope and limitations are described.