Tandem Palladium and Isothiourea Relay Catalysis: Enantioselective Synthesis of α-Amino Acid Derivatives via Allylic Amination and [2,3]-Sigmatropic Rearrangement
作者:Stéphanie S. M. Spoehrle、Thomas H. West、James E. Taylor、Alexandra M. Z. Slawin、Andrew D. Smith
DOI:10.1021/jacs.7b05619
日期:2017.8.30
has been developed for the enantioselective synthesis of α-aminoacid derivatives containing two stereogenic centers from readily accessible N,N-disubstituted glycine aryl esters and allylic phosphates. The optimized process uses a bench-stable succinimide-based Pd precatalyst (FurCat) to promote Pd-catalyzed allylic ammonium salt generation from the allylic phosphate and the glycine aryl ester. Subsequent
Neat cinnamyl fluoride, geranyl fluoride, 5-carbomethoxy-3-fluorocyclohexene and parent 3-fluorocyclohexene undergo spontaneous decomposition on contact with borosilicate glass or catalytic quantities of moderately strong acids that consists in polycondensation with elimination of HF initiated by electrophilic abstraction of F−. Acid sensitivity of these allylicfluorides correlates with stability
A simple and efficient method for the allylation of heteroarenes catalyzed by PdCl2
作者:Feng-Quan Yuan、Feng-Yi Sun、Fu-She Han
DOI:10.1016/j.tet.2012.06.038
日期:2012.8
produced was non-toxic aceticacid. Thus, the method presented in this work provides a general, clean, and operationally simple approach for the functionalization of heteroarenes. Finally, a preliminary mechanistic study suggested that the Pd(II) may be reduced in situ by the heteroarenes to Pd(0), which serves as the active metal center to catalyze the following allylations of heteroarenes via a Tsuji–Trost
Ni-Catalyzed Cross-Electrophile Coupling for the Synthesis of Skipped Polyenes
作者:Catherine P. McGeough、Alexandra E. Strom、Timothy F. Jamison
DOI:10.1021/acs.orglett.9b01019
日期:2019.5.17
Skipped polyenes featuring high ( E)-selectivity and varying methyl substitution patterns are synthesized using a nickel-catalyzed cross-coupling reaction between allyl trifluoroacetates and vinyl bromides. The utility of this cross-electrophile coupling is showcased in part by the synthesis of the RST fragment of the marine ladder polyether, maitotoxin. Construction of this fragment is particularly
Copper-Catalyzed Decarboxylative Trifluoromethylation of Allylic Bromodifluoroacetates
作者:Brett R. Ambler、Ryan A. Altman
DOI:10.1021/ol402780k
日期:2013.11
this transformation typically requires four-step processes, specialty chemicals, and/or stoichiometric metals to access the trifluoromethyl-containing product. A two-step copper-catalyzed decarboxylative protocol for converting allylic alcohols to trifluoromethanes is reported. Preliminary mechanistic studies distinguish this reaction from previously reported Cu-mediated reactions.