Separation-free determination of enantiomeric composition is valuable for the rapid evaluation of chiral nitrogen-containing compounds, but chromatographic analysis is often substrate-specific and may require tailored conditions. Here, we report probe 4, a cyclorhodium(III) complex bearing a CF3 reporter designed to convert analyte coordination into well-resolved 19F NMR readouts. The design integrates a rigid Rh(III)-centered cyclometalated scaffold, a compact trifluoromethyl reporter, and an accessible coordination site for nitrogen donors. Direct mixing with amino alcohols, primary amines, or nitriles gives new 19F resonances under slow exchange on the NMR time scale. The probe resolves a broad amine panel with R s values of up to 92.4 and extends to weakly coordinating nitriles bearing ester, amide, acid, cyclic, and quaternary stereocenter motifs. Five-component amine and six-component nitrile mixtures were resolved in a single NMR tube. Direct crude-product analysis of copper-catalyzed asymmetric decarboxylative cyanation gives ee values consistent with those of chiral HPLC. This Rh(III)-centered 19F NMR platform combines broad nitrogen donor compatibility, spectral simplicity, multiplex readout, and quantitative ee analysis.

Due to the importance of difluoromethylene unit in medicinal chemistry, increasing attention has been paid to the development of methodologies for the efficient and diversified syntheses of the molecules with this unit. Herein, we report a highly regioselective and stereoselective hydrocarboxylation of gem-difluoroallenes with carboxylic acids via the intermediacy of allylic palladium species. This reaction exhibits a broad substrate scope accommodating various synthetically versatile functional groups. By applying the protocol, we have achieved the late-stage modification of a series of drugs and bioactive molecules, and successfully developed a range of potential molecules with difluoromethylene units, providing a novel platform for future drug discovery.

Alkane dehydrogenation has evolved from a fundamental organometallic challenge into a transformative technology for upgrading abundant hydrocarbon feedstocks and modifying complex molecules. This Perspective charts the evolution of modern alkane dehydrogenation, emphasizing the strategic divergence between well-established two-electron pathways and emerging radical-mediated reaction manifolds. For the dehydrogenation of structurally unbiased simple alkanes, research remains centered on noble-metal-based molecular catalysts, represented by pincer-transition-metal systems, where activity and regioselectivity are not only governed by catalysts' first coordination sphere but also subtly affected by ligands' scaffold. In contrast, for the dehydrogenation of hydrocarbons with electronically or thermodynamically differentiated C(sp3)-H bonds, a complementary paradigm has emerged in which reactivity is mainly dictated by the intrinsic properties of substrates. The interplay of bond dissociation energies (BDEs) and bond polarity can be harnessed by a diverse array of hydrogen atom transfer (HAT) reagents (or catalysts). We discuss how these two distinct mechanisms dictate the scope of both the dehydrogenation and dehydrogenation-triggered derivatization, which extends beyond small alkane functionalizations to controlled upcycling of macromolecular polyolefins. By analyzing the interplay between thermodynamic constraints, catalyst sustainability, and process integration, we outline a forward-looking roadmap for next-generation catalytic dehydrogenation systems.

Loss of major histocompatibility complex class I (MHC-I) molecules from the tumor cell surface is a common mechanism of immune evasion; yet, the receptor intrinsic events that initiate their endocytic removal remain unclear. Here, using HLA-A*11:01, a human MHC-I heavy chain allotype as a model, we identify a membrane responsive regulatory module within its cytoplasmic tail. The conserved 360-365 segment engages phospholipid membranes and undergoes Cys363-dependent self-association under membrane mimetic conditions, while cooperating with the transmembrane region to shape the molecular proximity of full-length HLA-A. Disruption of this segment weakens association with the trafficking GTPase ARF6, slows receptor internalization, and prolongs HLA-A retention at the cell surface. Consistently, a cell penetrating peptide containing this sequence limits endogenous HLA-A internalization across several tumor cell lines. These findings identify the HLA-A cytoplasmic tail as an active regulator of endocytic trafficking and suggest a strategy for preserving surface HLA-A availability in tumor cells.

Chiral allenes and alkynes are privileged scaffolds in natural products and pharmaceuticals. Although significant advances have been achieved in catalytic asymmetric synthesis from diazo compounds, selectively achieving high levels of both enantioselectivity and regioselectivity from the same starting materials remains challenging. Herein, we report a tunable organocatalytic strategy for the divergent synthesis of chiral allenamides and propargylamides via the Wolff rearrangement of alkynyl diazoketones. By modulating chiral bifunctional catalysts and Lewis acid additives, we achieved excellent control over site selectivity and enantioselectivity. The method features a broad substrate scope, scalability, and applications in late-stage modification of complex molecules, providing a versatile route to valuable enantioenriched building blocks.

Late transition-metal imido species serve as key intermediates in a variety of catalytic transformations. However, their transient nature renders isolation challenging, and an isolable platinum terminal imido complex has remained elusive to date. In this work, we present a platinum terminal imido complex [( tBuXantphos)Pt(kappa-N-NTs)] ( tBuXantphos = 9,9-dimethyl-4,5-bis(di-tert-butylphosphino)xanthene, Ts = tosyl) that was prepared by the reaction of the platinum(0) complex [( tBuXantphos)Pt] with tosyl azide and fully characterized by NMR spectroscopy, single-crystal X-ray diffraction, and a Pt L 3-edge X-ray absorption near-edge structure study. The platinum imido complex features a Pt-N distance of 1.978(6) & Aring; and a bent Pt-N-S angle of 131.0(4) degrees. Computational studies suggest that the Pt-N bond is essentially a polarized sigma-bond with weak pi-interaction character and is associated with a strong attractive electrostatic interaction. Reactivity studies revealed that the platinum imido complex can perform nitrene transfer reactions with phosphines, CO, and isocyanides, and can also react with electrophiles to generate platinum(II) amido compounds as well as ion-pair species containing an amide anion as the counterion.