Metal Carbene Cycloaddition Reactions

Stereoretentive Catalytic [3+2]-Cycloaddition/Rearrangement/Decarboxylation Reactions of Indoles with Non-Racemic Donor–Acceptor Cyclopropanes

“…[3+n]-Cycloaddition reactions have become useful transformations for the construction of carbocyclic and heterocyclic compounds . Major contributions have come from catalytic reactions of vinyldiazo compounds and methods that employ donor–acceptor cyclopropanes, with both processes offering mechanistic and structural advantages in ring formation. For the asymmetric synthesis of chiral compounds, the use of vinyldiazo compounds requires a metal catalyst with chiral ligands (Scheme a), and although the vast majority of asymmetric cycloaddition reactions of donor–acceptor cyclopropanes are performed with racemic cyclopropane compounds catalyzed by Lewis acids with chiral ligands, optically active cyclopropane compounds can serve the same role using Lewis acids without chiral ligands .…”

Running Wild through Dirhodium Tetracarboxylate-Catalyzed Combined CH(C)-Functionalization/Cope Rearrangement Landscapes: Does Post-Transition-State Dynamic Mismatching Influence Product Distributions?

“…In addition, the presence of CC π bonds in the reactants leads to a competition between C–H and CC functionalization; Scheme shows that products of the CC functionalization are also sometimes observed. We also explore whether the TS for C–C bond formation is followed by a bifurcation that provides pathways to two C–C functionalized products, one a cyclopropane, that are also related by a Cope rearrangement (Scheme , top right), another reaction studied experimentally by Davies and co-workers. , We refer to this reaction as a “combined C–C functionalization/Cope rearrangement” (CCCR).…”

“…We also explore whether the TS for C−C bond formation is followed by a bifurcation that provides pathways to two C−C functionalized products, one a cyclopropane, that are also related by a Cope rearrangement (Scheme 1, top right), another reaction studied experimentally by Davies and co-workers. 35,36 We refer to this reaction as a "combined C−C functionalization/Cope rearrangement" (CCCR). These networks of reactions are much more complex than those encountered in our previous AIMD studies on Rh 2 L 4promoted β-lactone formation via C−H insertion.…”

Construction of Diazo Compounds via Catalytic [3 + 2] Annulation of Vinyldiazoacetates and Their Synthetic Applications

“…Vinyldiazo compounds prove to be versatile reactants for the synthesis of complex products. Their transition-metal-catalyzed reactions that form metal carbene intermediates provide access to a variety of natural products through cyclopropanation and C–H insertion, as well as to diverse carbocyclic and heterocyclic compounds by intermolecular [3 + n ]-cycloaddition . Their reactions with electrophiles can occur either at the vinylogous position or at the diazo carbon.…”