Epoxide-opening ether cyclizations are shown to occur on π-acidic aromatic surfaces without the need of additional activating groups and with autocatalytic amplification. Increasing activity with the intrinsic π acidity of benzenes, naphthalenediimides (NDIs) and perylenediimides (PDIs) support that anion−π interactions account for function. Rate enhancements maximize at 270 for anion−π catalysis on fullerenes and at 5100 M–1 for autocatalysis. The occurrence of anion−π autocatalysis is confirmed with increasing initial rates in the presence of additional product. Computational studies on autocatalysis reveal transition state and product forming a hydrogen-bonded noncovalent macrocycle, like holding their hands and dancing on the active π surface, with epoxide opening and nucleophile being activated by anion−π interactions and hydrogen bonds to the product, respectively.

Graphene/Cu composites were fabricated through a graphene in-situ grown approach, which involved ball-milling of Cu powders with PMMA as solid carbon source, in-situ growth of graphene on flaky Cu powders and vacuum hot-press sintering. SEM and TEM characterization results indicated that graphene in-situ grown on Cu powders guaranteed a homogeneous dispersion and a good combination between graphene and Cu matrix, as well as the intact structure of graphene, which was beneficial to its strengthening effect. The yield strength of 244 MPa and tensile strength of 274 MPa were achieved in the composite with 0.95 wt.% graphene, which were separately 177% and 27.4% enhancement over pure Cu. Strengthening effect of in-situ grown graphene in the matrix was contributed to load transfer and dislocation strengthening.

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The reaction of the readily available N-methyl-N-phenylcinnamamides with phenyliodine bis(trifluoroacetate) (PIFA) in the presence of Lewis acids provides a general and efficient assembly of a variety of 3-arylquinolin-2-one compounds. This novel approach features not only metal-free oxidative C(sp(2))-C(sp(2)) bond formation but also an exclusive 1,2-aryl migration.

A series of indoloquinolinones bearing different aromatic substitutents were readily synthesized starting from an aryl amine, a methyl 3-oxo-3-phenylpropanoate derivative, and methoxylamine through a series of reactions of coupling/enamination, oxidative annulation, a one-pot sequence of N-alkylation, saponification and methoxyamidation, and final intramolecular oxidative C-N bond formation. The underpinning of the strategy entails Pd(OAc)2/Cu(OAc)2-mediated oxidative C(sp(2))-C(sp(2)) bond formation and I(III)-mediated oxidative C(sp(2))-N bond formation.

An exclusive trans-aminocarboxylation and oxoaminocarboxylation of diarylalkynes were realized through hypervalent iodine-mediated cascade annulations under metal-free conditions, leading to divergent assembly of fused or spiro polycyclic heterocycles with a dosage of the hypervalent iodine oxidant. The mechanisms for the formation of both products are proposed.

In Memory of Gilbert StorkAnion-p interactions have been recently introduced to catalysis with the idea to stabilize anionic intermediates on p-acidic surfaces. Realized examples include enolate, enamine and iminium chemistry, domino processes and DielsAlder reactions. Moving on from the formation of contiguous stereogenic centers on p-acidic surfaces, herein we report the first asymmetric anion-p catalysis of cascade reactions that afford nonadjacent stereocenters. Conjugate addition-protonation of achiral disubstituted enolate donors to 2-chloroacrylonitrile generates 1,3-nonadjacent stereocenters with moderate enantioselectivity and diastereoselectivity. The explored catalysts operate with complementary naphthalenediimide and fullerene surfaces with highly positive quadrupole moments and high polarizability, respectively, and proximal amine bases. We find that anion-p catalysts can increase the diastereoselectivity of the reaction beyond the maximal 1:4.0 dr with conventional catalysts to maximal 5.3:1 dr on the large fullerene surfaces. The enantioselectivity of anion-p catalysts, best on the confined naphthalenediimide surfaces with strong quadrupole moment, exceed the performance of conventional catalysts except for comparable results with a new, most compact, surprisingly powerful bifunctional control catalyst. Simultaneously increased rates and stereoselectivities compared to control catalysts without p-acidic surface support that contributions of anion-p interactions to the catalytic cascade process are significant.