Organic Letters

Abstract The translation of C–H activation into practical platforms for bioactive molecule discovery remains constrained by poor functional group compatibility, limited scalability, and inefficient downstream diversification. Here we present a robust and scalable, redox-neutral C–H amination strategy that overcomes these challenges through the synergistic use of readily installed and traceless im…

Abstract An efficient kinetic resolution of binaphthyl triflates is developed via Ni-catalyzed asymmetric C(sp2)–P cross-coupling to access substituted atropisomeric phosphines. Moreover, the phosphine framework showed superior reactivity and enantiocontrol in Pd-catalyzed asymmetric allylic substitution. Mechanistic control experiments revealed that the introduction of a pyridine ring provides b…

Abstract Herein, we report a palladium-catalyzed domino arylation/dehydrogenative aromatization of acylcyclohexenes to synthesize meta-aryl acetophenone derivatives. This strategy achieves a previously elusive formal meta-C–H arylation of ketones, even with heteroaryl halides. It allows the late-stage introduction of fluorophores and supramolecular motifs, and the robustness is demonstrated by co…

Abstract We report a Rh(III)-catalyzed C–H activation and strain-release cascade that merges inert C–H bond functionalization with the ring opening of bicyclo[1.1.0]butanes (BCBs) to directly access conjugated dienes. The reaction leverages the unique alkene-like reactivity of the BCB bridgehead bond and the versatility of Rh(III) catalysis to enable simultaneous C–H cleavage and C–C scission, of…

Abstract A series of double [5]helicenes with a triptycene core were synthesized via photocyclization. Single-crystal X-ray analysis unambiguously confirms these helicenes with an R/S triptycene core and two M/P [5]helicene subunits. Transfer of the central axially helical chirality was observed from R/S-tripytycene as reflected in the diastereoselective, photochemical formation of M/P-[5]helicen…

Abstract Chiral fluorescent probes based on small organic molecules present a promising platform for advanced bioimaging applications. In this work, we have developed a helically chiral spiro-shaped carbofluorescein with red emission (λem ≤ 613 nm). Configurationally stable enantiomers were separated, and electronic circular dichroism (ECD) and circularly polarized luminescence (CPL) evaluated. P…

Abstract A heterogeneous Ru2/Pt1-H-ZSM-5 catalyst achieves regioselective hydrogenation of 2-naphthol into 5,6,7,8-tetrahydro-2-naphthol at 25 °C. Complete conversion and an 81.8% yield are attained, affording a yield rate higher than that of reported homogeneous catalysts. The synergy between the Ru–Pt alloy and acid sites facilitates coplanar adsorption of the electron-rich phenol ring in 2-nap…

Abstract Allyl trisilylanes, as synthetically accessible surrogates of allylic trimetallic reagents, may play a pivotal role in organic synthesis, particularly in transition-metal-catalyzed transformations and the construction of complex molecular architectures. Herein, we report an iron-catalyzed trisilylation of 1,3-diene electrophiles bearing an SMe leaving group, providing efficient access to…

Abstract α-Naphthol constitutes the core scaffold of numerous anti-inflammatory and antitumor bioactive molecules, while conventional synthetic approaches suffer from harsh reaction conditions. Herein, a visible-light-catalyzed radical cascade cyclization is developed for the efficient assembly of α-naphthol derivatives using readily available phosphorus ylides and alkynes. With 4DPAIPN or fac-Ir…

Abstract Herein, we report a transition-metal-free organophotocatalytic strategy for the deoxygenative formation of C(sp3)–N bonds from readily available alcohols. The method employs diaryl ketone O-aroyl oximes as bifunctional reagents, serving as both radical precursors and nitrogen sources. Under mild visible-light irradiation, primary, secondary, and tertiary alcohol-derived xanthates are eff…

Abstract We report herein a simple and general photoinduced iron-catalyzed method that combines 1,2-functional group migration (1,2-FGM) with ligand-to-metal charge transfer (LMCT) and radical ligand transfer (RLT) to broaden the reaction profiles of alkene 1,3-difunctionalization. Based on this synergistic concept, the first 1,3-diazidation and 1,3-dichlorination of β,γ-unsaturated ketones via 1…

Abstract Arylboronic esters are indispensable intermediates in synthesis. We report a direct deaminative borylation of anilines enabled by anomeric amide activation with copper catalysis. The transformation proceeds via in situ generation of aryl radicals from isodiazene intermediates, followed by interception with a Cu–Bpin species derived from bis(pinacolato)diboron. Key to the success of this …

Abstract Diazaxanthilidene dyes are photoconvertible small-molecule fluorophores with applications in live-cell imaging. Synthetic access has been limited by challenging dimerization reactions required to construct the sterically hindered tetrasubstituted olefin core. Herein, we report a TMS-diazomethane-mediated thione dimerization, and key intermediate, that enables rapid access to this framewo…

Abstract Functionalized ketones and alcohols are two privileged scaffolds widely found in natural products and biologically active compounds. They are also key synthetic intermediates in target-oriented synthesis. The divergent synthesis of ketones and alcohols from the same starting materials and catalysts via the borrowing hydrogen (BH) reaction is of great significance. Despite the significant…

Abstract An anion-switch strategy employing a hypervalent iodine/protic acid system achieves programmable pathway bifurcation following pyrimidine dearomatization. Changing the acid counterion precisely diverts the reaction trajectory: triflic acid promotes ring-contractive dearomatization to imidazolines, whereas hydrogen halides trigger ring-retentive dearomatization to halogenated hydropyrimid…

Abstract The first total synthesis of (±)-caryopincaolide A, a rearranged abeo-abietane diterpenoid containing a 5/6/6 fused skeleton and three contiguous all-carbon quaternary centers, is described. The route installs the aromatic ring at an early stage and assembles the congested framework in a C/B → A sequence. An Fe(acac)3/PhSiH3-mediated reductive alkene–enone coupling is the key skeleton-fo…

Abstract Herein, we report a reusable UiO-67-Pd catalyst for additive-free transfer hydrogenation of epoxides at room temperature using ammonia borane as the hydrogen source. The protocol enables selective conversion of aromatic and aliphatic epoxides into the corresponding alcohols and can be readily applied to the reduction of other unsaturated functionalities, including α,β-unsaturated ketones…

Abstract Tropone-based cyclic β2,3-amino acids are rare nonproteinogenic amino acid scaffolds with limited synthetic tractability. Herein, we report a concise synthesis of tropono-β2,3-amino acid derivatives from readily available phenols and nitriles via oxidative dearomatization followed by a one-pot Michael addition/retro-6π electrocyclization/oxidation sequence. Control experiments and DFT ca…

Abstract A straightforward strategy for the electrochemical amidation of benzyl halides via radical-polar crossover has been developed. The reaction was carried out with acetonitrile as both the solvent and the amidation reagent and (PhS)2 as a “radical shuttle”. Various N-substituted acetamide products can be afforded from benzyl halides under metal- and oxidant-free electrochemical conditions. …

Abstract A sustainable parallel paired electrolysis methodology has been developed to synthesize α-hydroxy amides via hydride-free reduction of α-keto amides at the cathode and the esterification of aldehydes at the anode. Interestingly, any substitution at the α-keto amide not only affects the yield of the reduction process but also influences the oxidation process due to potential alignment. Ra…