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Rocks may exhibit time-dependent behaviors. Long-term strength criterion significantly dominates creep failure of rocks. Rocks contain many microcracks, which lead to degrade of long-term strength. In this paper, it is assumed that there exist three-dimensional penny-shaped microcracks in rocks. The mode II stress intensity factors at tips of three-dimensional pennyshaped microcracks in Burgers viscoelastic rock matrix is derived. A novel micromechanics-based three-dimensional long-term strength criterion is established to consider the effects of time and the intermediate principal stress on creep failure of rocks. By comparison with the previous experimental data, it is found that the novel micromechanics-based threedimensional long-term strength criterion is in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

A new route is presented for the selective assembly of isoquinolines and indenes by rhodium-catalyzed tandem cyclization of benzylidenehydrazones with internal alkynes. This method involves the selective cleavage of the N-N bond and the C=N bonds and is dependent on the substituents of the benzylidenehydrazone. [ABSTRACT FROM AUTHOR]

A novel and general halopalladation/decarboxylation/carbon−carbon forming domino protocol is described for the synthesis of 5-halo-6-substituted benzo[b]naphtho[2,1-d]furans. The protocol represents the first example of trapping the σ-vinylpalladium intermediate, generated from halopalladation of alkynes, by the decarboxylative coupling reaction. [ABSTRACT FROM AUTHOR]

A mild and general cycloaddition of arynes with iodonium ylides protocol has been developed for the synthesis of benzofurans. In the presence of CsF, ortho-silyl aryltriflates were reacted with iodonium ylides smoothly at room temperature in moderate to good yields. [ABSTRACT FROM AUTHOR]

A novel palladium-catalyzed methylation protocol for the synthesis of methyl-functionalized internal alkynes has been established. This methylation method is achieved through a C(sp)-C(sp³) bond formation process and represents a new synthetic application of sulfonium ylides. [ABSTRACT FROM AUTHOR]

A general and mild method for the construction of functionalized 2-(1H-indol-3-yl)-2-amino-carbonyl compounds was achieved, which represents the first example of direct α-arylation of α-amino carbonyl compounds with indoles using the visible light photoredox catalysis strategy. [ABSTRACT FROM AUTHOR]

A selective protocol for the synthesis of 2-methylene-3- substituted-2,3-dihydro-1H-inden-1-Ones and 2-benzylidene-2,3-dihydro-1H-inden-1-ones has been developed via palladium-catalyzed cyclocarbonylation reactions of arynes with allyl carbonates and carbon monooxide (CO). It is noteworthy that the selectivity of this new route is depended on both substrates and ligands. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed cocyclotrimerization of allenes with arynes has been developed for selectively synthesizing phenanthrenes. In the presence of [(allyl)PdCl]2 and P(o-tol)3, a variety of allenes, including internal and terminal allenes, underwent the cocyclotrimerization with arynes to afford the corresponding phenanthrenes in moderate to good yields. The results showed the selectivity of the reaction based on allenes. [ABSTRACT FROM AUTHOR]