THE SYNTHESIS AND CONFIGURATIONS OF UNSATURATED 1,4-DIKETONES AND KETONIC ACIDS, AND THE STEREOCHEMICAL MECHANISM OF THE ADDITION OF BROMINE. STUDIES ON UNSATURATED 1,4-DIKETONES. VI
Chiral amine–imine ligands based on trans-2,5-disubstituted pyrrolidines and their application in the palladium-catalyzed allylic alkylation
作者:Hongfeng Chen、James A. Sweet、Kin-Chung Lam、Arnold L. Rheingold、Dominic V. McGrath
DOI:10.1016/j.tetasy.2009.07.010
日期:2009.7
moiety affords dramatic changes on the outcome of the stereochemistry. Evidencefrom various studies suggested that during the palladium-catalyzed allylic alkylation reaction, nucleophilicattack onto the 1,3-diphenylallyl moiety in the transition state occurs mainly trans to the pyridine ring of the less stable conformation of the palladiumcomplexes.
A copper(I)/DDQ-mediated double-dehydrogenative Diels–Alder (DDDA) reaction of simple butenes with 1,4-diketones and indolones has been established for the first time. This strategy is based on a tandem double-dehydrogenation/Diels–Alderreaction from nonprefunctionalized starting materials, in which both a diene and dienophile were in situgenerated via activation of fourfold inert C(sp3)–H bonds
Reaction of 1,2-diaryl-3,4-dibromocyclo-but-1-enes (4) with silver perchlorate in the presence of water gave (E)-2,3-diarylbut-2-enedials (5), which when treated with acid were converted into 2,3-diarylbut-2-en-4-olides (6).