An organocatalytic asymmetric formal [3+2] cycloaddition of isatin-derived 3-indolylmethanol with 3-methyl-2-vinylindole has been established, leading to highly stereoselective construction of a spiro[cyclopenta[b]indole-1,3'-oxindole] scaffold with the concomitant creation of three contiguous stereogenic centers (72-99% yield, all >95 : 5 dr, 90-98% ee), one of which is an all-carbon quaternary stereogenic center.

C(sp 3 )À H bond coupling with carbon electrophiles remains rarely explored under thermo-driven hydrogen atom transfer (HAT) conditions due to the challenge of integrating oxidation and reduction in a single operation. We report here a Ni-catalyzed arylation and alkylation of C(sp 3 )À H bonds with organohalides to forge C(sp 3 )À C bonds by merging economical Zn and tBuOOtBu (DTBP) as the external reductant and oxidant. The mild and easy-to-operate protocol enables facile carbofunctionalization of N-/O-α-and cyclohexane CÀ H bonds, and preparation of a few intermediates of bioactive compounds and drug derivatives. Preliminary mechanistic studies implied addition of an alkyl radical to a Ni II salt.

We present an isogeometric boundary element method (IGABEM) capable of delivering accurate and efficient solutions in the heat transfer analysis of 2D coated structures such as those commonly found in turbomachinery. Although we consider very thin coatings (of thickness down to 10 −7 m), they are modelled explicitly as BEM zones, and this is made possible by the development of a new integration scheme (sinh +) aimed particularly at the challenging nearly singular integrals that arise. Sinh + is a hybrid of adaptive and sinh transformation approaches, and we make further extensions to the latter to improve its robustness. The scheme is tuned to deliver results of engineering accuracy in an optimal time. The scheme is adaptable, by changing a tolerance, to enable engineers to achieve a different balance between accuracy and computational efficiency as may be required for different applications. A set of numerical examples demonstrates the ability of the scheme to produce accurate temperature distributions efficiently in the presence of very thin coatings.

Circulant matrices have important applications in solving ordinary differential equations. In this paper, we consider circulant-type matrices with thek-Fibonacci andk-Lucas numbers. We discuss the invertibility of these circulant matrices and present the explicit determinant and inverse matrix by constructing the transformation matrices, which generalizes the results in Shen et al. (2011).

Real-time temperature feedback in tissue based on photothermal therapy is an urgent problem to be solved in cancer treatment. Herein, a smart all-in-one nanoprobe THA@Eu-NMOF@Fe/TA was designed and assembled by postsynthetical functionalization of an Eu­(III)-based nanoscale metal–organic framework (Eu-NMOF) with a two-photon-absorbing β-diketonate ligand 4,4,4-trifluoro-1-(9-hexylcarbazol-3-yl)-1,3-butanedione (HTHA) and Fe­(III)/tannic acid assembly (Fe/TA). Such a functionalized material can simultaneously achieve the temperature-sensing and optical heating under a single beam of near-infrared (NIR) light. Under 808 nm laser excitation, real-time feedback of temperature by monitoring thermoresponsive fluorescence emission ratio (I 616/I 590) and fluorescence lifetime of Eu­(III) ions were realized. Meantime, Fe/TA served as the photothermal agent and antibacterial agent to implement photothermal therapy (PTT) and antibacteria simultaneously. The functions of the nanoprobe were proved with ex vivo experiments, and the antibacterial activity against Gram-positive and Gram-negative bacteria of the probe was also elaborately evaluated. Our work paves a new avenue for engineering a new cancer treatment probe which can achieve real-time temperature sensing feedback during PTT and antibacterial process.

A nickel-catalyzed reductive coupling of aryl triflates with thiocarbonates is reported here. Both electron-rich and -deficient aryl C­(sp2)–O electrophiles as well as a class of O-tBu S-alkyl thiocarbonates are compatible with the optimized reaction conditions, as evidenced by 49 examples. The reaction also proceeds with good chemoselective cleavage of the C–O bond with regard to thioesters. This work broadens the scope of nickel-catalyzed reductive cross-electrophile coupling reactions.

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Hybrid nearly singular integration for three-dimensional isogeometric boundary element analysis of coatings and other thin structures.', Computer methods in applied mechanics and engineering., 367 . p. 113099.