The asymmetric total synthesis of (+)-waihoensene, which has a cis-fused [6,5,5,5] tetracyclic core bearing an angular triquinane, a cis-fused six-membered ring, and four contiguous quaternary carbon atoms, was achieved through a sequence of chemical reactions in a stereochemically well-defined manner. The total synthesis features the following: (1) Cu-catalyzed asymmetric conjugated 1,4-addition; (2) diastereoselective Conia-ene type reaction; (3) diastereoselective intramolecular Pauson− Khand reaction; (4) Ni-catalyzed diastereoselective conjugated 1,4-addition; and (5) radical-initiated intramolecular hydrogen atom transfer (HAT). Control experiments and density functional theory calculations support the proposed HAT process.

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We have developed a new headstage architecture as part of a smart experimental arena, known as the EnerCage-HC2 system, which automatically delivers stimulation and collects behavioral data over extended periods with minimal small animal subject handling or personnel intervention in a standard rodent homecage. Equipped with a 4-coil inductive link, the EnerCage-HC2 system wirelessly powers the receiver (Rx) headstage, irrespective of the subject’s location or head orientation, eliminating the need for tethering or carrying bulky batteries. On the transmitter (Tx) side, a driver coil, five high quality (Q) factor segmented resonators at different heights and orientations, and a closed-loop Tx power controller create a homogeneous electromagnetic (EM) field within the homecage 3-D space, and compensate for drops in power transfer efficiency (PTE) due to Rx misalignments. The headstage is equipped with four small slanted resonators, each covering a range of head orientations with respect to the Tx resonators, which direct the EM field towards the load coil at the bottom of the headstage. Moreover, data links based on Wi-Fi, UART, and Bluetooth low energy are utilized to enables remote communication and control of the Rx. The PTE varies within 23.6–33.3% and 6.7–10.1% at headstage heights of 8 and 20 cm, respectively, while continuously delivering >40 mW to the Rx electronics even at 90° rotation. As a proof of EnerCage-HC2 functionality in vivo, a previously documented on-demand electrical stimulation of the globus pallidus, eliciting consistent head rotation, is demonstrated in three freely behaving rats.

We developed an efficient visible-light-mediated formal carbene insertion reaction of 1,3-diketones with diazoesters for the construction of enantioenriched 1,4-dicarbonyl compounds with a quaternary carbon center. Combining visible light and a Brønsted acid catalyst, chiral 1,4-dicarbonyl compounds were achieved in good yields with high enantioselectivities by a photochemical carbene transfer protocol.

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Developing high-performance, low-loading, Ir-based electrocatalysts for the oxygen evolution reaction (OER) in acidic media is still a great challenge. Herein, we fabricated an iridium manganese catalyst with only 5 % iridium. The influence of the manganese dioxide phase states (α-, β-, γand δ-MnO 2) on the OER performance of IrO 2 /MnO 2 catalysts was investigated. α-MnO 2 , as the substrate, can generate smaller iridium particles and more high-valence-state iridium to promote OER performance. Therefore, the 5 % IrO 2 /α-MnO 2 electrocatalyst exhibits excellent electrocatalytic OER performance with a high mass activity of 216.67 A/g Ir and 655.33 A/g Ir at 1.53 V in acidic and alkaline media, respectively, significantly outperforming commercial IrO 2 .

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An efficiently stereoselective [4 + 2] cycloaddition of 3-alkylenyloxindoles and α-diazoketones through sequential visible-light photoactivation and N-heterocyclic carbene catalysis was achieved. A series of tetrahydropyrano­[2,3-b]­indoles with an all-carbon quaternary stereocenter were obtained in good yields with excellent diastereo- and enantioselectivities.