C(2)-symmetric bis(oxazolinato)lanthanide complexes of the type [(4R,5S)-Ph(2)Box]La[N(TMS)(2)](2), [(4S,5R)-Ar(2)Box]La[N(TMS)(2)](2), and [(4S)-Ph-5,5-Me(2)Box]La[N(TMS)(2)](2) (Box = 2,2'-bis(2-oxazoline)methylenyl; Ar = 4-tert-butylphenyl, 1-naphthyl; TMS = SiMe(3)) serve as precatalysts for the efficient enantioselective intramolecular hydroamination/cyclization of aminoalkenes and aminodienes. These new catalyst systems are conveniently generated in situ from the known metal precursors Ln[N(TMS)(2)](3) or Ln[CH(TMS)(2)](3) (Ln = La, Nd, Sm, Y, Lu) and 1.2 equiv of commercially available or readily prepared bis(oxazoline) ligands such as (4R,5S)-Ph(2)BoxH, (4S,5R)-Ar(2)BoxH, and (4S)-Ph-5,5-Me(2)BoxH. The X-ray crystal structure of [(4S)-(t)BuBox]Lu[CH(TMS)(2)](2) provides insight into the structure of the in situ generated precatalyst species. Lanthanides having the largest ionic radii exhibit the highest turnover frequencies as well as enantioselectivities. Reaction rates maximize near 1:1 BoxH:Ln ratio (ligand acceleration); however, increasing the ratio to 2:1 BoxH:Ln decreases the reaction rate, while affording enantiomeric excesses similar to the 1:1 BoxH:Ln case. A screening study of bis(oxazoline) ligands reveals that aryl stereodirecting groups at the oxazoline ring 4 position and additional substitution (geminal dimethyl or aryl) at the 5 position are crucial for high turnover frequencies and good enantioselectivities. The optimized precatalyst, in situ generated [(4R,5S)-Ph(2)Box]La[N(TMS)(2)](2), exhibits good rates and enantioselectivities, comparable to or greater than those achieved with chiral C(1)-symmetric organolanthanocene catalysts, even for poorly responsive substrates (up to 67% ee at 23 degrees C). Kinetic studies reveal that hydroamination rates are zero order in [amine substrate] and first order in [catalyst], implicating the same general mechanism for organolanthanide-catalyzed hydroamination/cyclizations (intramolecular turnover-limiting olefin insertion followed by the rapid protonolysis of an Ln-C bond by amine substrate) and implying that the active catalytic species is monomeric.

We developed a biodegradable photothermal therapeutic (PTT) agent, π-conjugated oligomer nanoparticles (F8-PEG NPs), for highly efficient cancer theranostics. By exploiting an oligomer with excellent near-infrared (NIR) absorption, the nanoparticles show a high photothermal conversion efficiency (PCE) up to 82%, surpassing those of reported inorganic and organic PTT agents. In addition, the oligomer nanoparticles show excellent photostability and good biodegradability. The F8-PEG NPs are also demonstrated to have excellent biosafety and PTT efficacy both in vitro and in vivo. This contribution not only proposes a promising oligomer-based PTT agent but also provides insight into developing highly efficient nanomaterials for cancer theranostics.

The total syntheses of the pyrrolidine alkaloid (+)-197B (1) and pyrrolizidine alkaloid (+)-xenovenine (2) are described. The strategy involves enantioselective syntheses of the aminoallene, (5S,8S)-5-amino-trideca-8,9-diene (3), and the aminoallene-alkene, (5S)-5-amino-pentadeca-1,8,9-triene (4), which then undergo regio- and stereoselective cyclohydroamination catalyzed by the organolanthanide precatalysts Cp‘2LnCH(TMS)2 and Me2SiCp‘ ‘(tBuN)LnN(TMS)2 (Cp‘ = η5-Me5C5; Cp‘ ‘ = η5-Me4C5; Ln = lanthanide; TMS = Me3Si). These reactive organolanthanide complexes efficiently mediate highly diastereoselective intramolecular hydroamination/cyclization (IHC) reactions under mild conditions. The turnover-limiting step in these catalytic cycles is proposed to be intramolecular insertion into the Ln−N bond of the proximal allenic CC linkage, followed by rapid protonolytic cleavage of the resulting Ln−C bond. The rate and selectivity of the insertion process is highly sensitive to the steric demands of the substrate.

Extensive recent efforts have been put on the design of high‐performance organic near‐infrared (NIR) photothermal agents (PTAs), especially over NIR‐II bio‐window (1000–1350 nm). So far, the development is mainly limited by the rarity of molecules with good NIR‐II response. Here, we report organic nanoparticles of intermolecular charge‐transfer complexes (CTCs) with easily programmable optical absorption. By employing different common donor and acceptor molecules to form CTC nanoparticles (CT NPs), absorption peaks of CT NPs can be controllably tuned from the NIR‐I to NIR‐II region. Notably, CT NPs formed with perylene and TCNQ have a considerably red‐shifted absorption peak at 1040 nm and achieves a good photothermal conversion efficiency of 42 % under 1064 nm excitation. These nanoparticles were used for antibacterial application with effective activity towards both Gram‐negative and Gram‐positive bacteria. This work opens a new avenue into the development of efficient PTAs.

Potassium-ion capacitors (PICs) have received increasing attention because of their high energy/power densities and the abundance of potassium. However, achieving high-rate battery-type anode to match the capacitor-type cathode is still...