Rhodium(III)-Catalyzed Redox-Neutral Cascade [3 + 2] Annulation of <i>N</i>-Phenoxyacetamides with Propiolates via C–H Functionalization/Isomerization/Lactonization
A Rh(III)-catalyzed cascade [3 + 2] annulation of N-phenoxyacetamides with propiolates under mild conditions using the internal oxidative O–N bond as the directing group has been achieved. This catalytic system provides a regio- and stereoselective access to benzofuran-2(3H)-ones bearing exocyclic enamino motifs with exclusive Z configuration selectivity, acceptable to good yields and good functional
Oxidation of aromatic compounds: XII. Regio- and stereoselective oxidative dimerization of alkyl 3-arylpropynoates in the system CF3CO2H-CH2Cl2-PbO2
作者:P. Yu. Savechenkov、A. V. Vasil?ev、A. P. Rudenko
DOI:10.1007/s11178-005-0005-5
日期:2004.9
Regio- and stereoselective oxidative dimerization of alkyl 3-arylpropynoates in the system CF3CO2H-CH2Cl2-PbO2 (1–30 h, 0–20°C) leads to dialkyl (E)-2,3-bis(arylcarbonyl)-2-butene-1,4-dioates with trans arrangement of the substituents at the double bond.
A copper-promoted aerobic oxidative [3+2] cycloaddition reaction for the synthesis of various substituted pyrazoles from N,N-disubstituted hydrazines with alkynoates in the presence of bases is developed. This work involves a direct C(sp3)–H functionalization and the formation of new C–C/C–N bonds. In this strategy, inexpensive and easily available Cu2O serves as the promoter and air acts as the green