Tandem Gold/Silver-Catalyzed Cycloaddition/Hydroarylation of 7-Aryl-1,6-enynes to Form 6,6-Diarylbicyclo[3.2.0]heptanes
作者:Bradley D. Robertson、Rachel E. M. Brooner、Ross A. Widenhoefer
DOI:10.1002/chem.201500371
日期:2015.4.7
[PCy2(o‐biphenyl)}AuCl] and AgSbF6 catalyze the tandemcycloaddition/hydroarylation of 7‐aryl‐1,6‐enynes with electron‐rich arenes to form 6,6‐diarylbicyclo[3.2.0]heptanes in good yield under mild conditions. Experimental observations point to a mechanism involving gold‐catalyzed cycloaddition followed by silver‐catalyzed hydroarylation of a bicyclo[3.2.0]hept‐1(7)‐ene intermediate.
The synthesis of optically pure 2-pyridylphospholene ligands by diastereomeric resolution of PdII complexes, bearing the corresponding racemic P,N ligand and (R)-α-methylbenzylamine, by means of fractional crystallisation is described. A full coordination study of palladiumcomplexes containing 2-pyridylphospholene and the corresponding phosphole ligands, both in solution (by means of NMR spectroscopy)
The branched, chiral products 1 are formed preferentially in the allylicalkylations in Equation (1) when the Pd catalyst contains the P,N ligand L* or derivatives thereof. The ligands are readily synthesized from commercially available precursors.
Co‐catalyzedallylic substitution reactions have received little attention, arguably because of the lack of any known advantage of Co catalysis over either Rh or Ir catalysis. Described here is a general and regioselective Co‐catalyzedallylicalkylation using an in situ catalyst activation by organophotoredox catalysis. This noble‐metal‐free catalytic system exhibits unprecedentedly high reactivities
Reactions of allylic carbonates catalyzed by palladium, rhodium, ruthenium, molybdenum, and nickel complexes; allylation of carbonucleophiles and decarboxylation- dehydrogenation
作者:Ichiro Minami、Isao Shimizu、Jiro Tsuji
DOI:10.1016/0022-328x(85)80354-5
日期:1985.11
carbonucleophiles with allylic carbonatescatalyzed by various transition metal complexes has been studied. Palladium, rhodium, ruthenium, nickel, and molybdenum complexes were found to be active catalysts. The rhodium catalyst showed a different regioselectivity from the other catalysts, the reaction can proceed without allylic rearrangement. In the absence of nucleophiles, allyl alkyl carbonates were converted into