Dioxazolones as electrophilic amide sources in copper-catalyzed and -mediated transformations

• Seungmin Lee,
• Minsuk Kim,
• Hyewon Han and
• Jongwoo Son

Beilstein J. Org. Chem. 2025, 21, 200–216, doi:10.3762/bjoc.21.12

• dioxazolone bearing a phenyl group showed no reactivity toward benzoyl amidine under the optimized reaction conditions. Instead, the authors employed a less bulky copper iodide catalyst in the absence of phosphine, successfully affording aryloyl amidine 10f. Furthermore, the electron-rich ethynylanisole

• to yield the stable intermediate INT-21. This intermediate releases the N-acyl iminophosphorane 16 through the incorporation of another organic phosphine, thereby regenerating the active copper species 17. 1.6 Synthesis of N-sulfenamides In 2022, the research groups of Wang and Chen introduced a

Quantifying the ability of the CF₂H group as a hydrogen bond donor

• Matthew E. Paolella,
• Daniel S. Honeycutt,
• Bradley M. Lipka,
• Jacob M. Goldberg and
• Fang Wang

Beilstein J. Org. Chem. 2025, 21, 189–199, doi:10.3762/bjoc.21.11

• assigning specific contributions of each to the observed binding affinities. Even so, 1H NMR titration experiments with phosphine oxides still allow us to partially resolve these two forces by monitoring the proton of the CF2H group. Such issues are particularly salient when quantification methods that rely

Nickel-catalyzed cross-coupling of 2-fluorobenzofurans with arylboronic acids via aromatic C–F bond activation

• Takeshi Fujita,
• Haruna Yabuki,
• Ryutaro Morioka,
• Kohei Fuchibe and
• Junji Ichikawa

Beilstein J. Org. Chem. 2025, 21, 146–154, doi:10.3762/bjoc.21.8

• , entry 3). Reducing the catalyst loading to 5 mol % slightly affected the yield of 3bb, which was 90% (Table 1, entry 4). Next, we evaluated various additives with 5 mol % of Ni(cod)2 to stabilize regenerated zero-valent nickel species (Table 1, entries 5–8). While phosphine ligands such as triphenyl

Recent advances in organocatalytic atroposelective reactions

• Henrich Szabados and
• Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

Emerging trends in the optimization of organic synthesis through high-throughput tools and machine learning

• Pablo Quijano Velasco,
• Kedar Hippalgaonkar and
• Balamurugan Ramalingam

Beilstein J. Org. Chem. 2025, 21, 10–38, doi:10.3762/bjoc.21.3

Synthesis, characterization, and photophysical properties of novel 9‑phenyl-9-phosphafluorene oxide derivatives

• Shuxian Qiu,
• Duan Dong,
• Jiahui Li,
• Huiting Wen,
• Jinpeng Li,
• Yu Yang,
• Shengxian Zhai and
• Xingyuan Gao

Beilstein J. Org. Chem. 2024, 20, 3299–3305, doi:10.3762/bjoc.20.274

• phosphine oxide (PO) groups have recently received considerable attention for their high thermal stability and unique optoelectronic features, and thus being widely applied in organic light-emitting diodes (OLEDs) [1][2]. To date, tremendous efforts have been devoted to the development of a variety of high

Intramolecular C–H arylation of pyridine derivatives with a palladium catalyst for the synthesis of multiply fused heteroaromatic compounds

• Yuki Nakanishi,
• Shoichi Sugita,
• Kentaro Okano and
• Atsunori Mori

Beilstein J. Org. Chem. 2024, 20, 3256–3262, doi:10.3762/bjoc.20.269

• ; phosphine ligand; pyridine amides; Introduction Transition-metal-catalyzed synthetic reactions have recently attracted much attention in synthetic organic chemistry [1][2]. C–H Arylation reactions catalyzed by a transition metal are of particular interest because these reactions involve rather superior

• effective to afford 2a in 94% yield. The reaction was then carried out with several pyridine derivatives including amide derivatives composed of 6-methylpicoline (1b) and unsubstituted picoline (1c) as summarized in Table 2. When the reaction was examined in the absence of a phosphine ligand, the yields of

• palladium catalyzed C–H arylation to pyridine derivatives. The cyclization reaction proceeded in a moderate to excellent yield when an appropriate phosphine ligand was employed. The reaction is expected to be useful for the synthesis of functional materials, and bioactive molecules in a facile manner

Recent advances in transition-metal-free arylation reactions involving hypervalent iodine salts

• Ritu Mamgain,
• Kokila Sakthivel and
• Fateh V. Singh

Beilstein J. Org. Chem. 2024, 20, 2891–2920, doi:10.3762/bjoc.20.243

N-Glycosides of indigo, indirubin, and isoindigo: blue, red, and yellow sugars and their cancerostatic activity

• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 2840–2869, doi:10.3762/bjoc.20.240

• -rhamnosides β-16g–j were prepared from the corresponding anilines as exemplified above for the synthesis of β-16a. Treatment of β-16a,g–j with tris(diethylamino)phosphine resulted in formation of dimers β-59a–e in good yields (Scheme 36) [58]. Deprotection afforded the desired isoindigo-N,N‘-dirhamnosides β

Synthesis of fluoroalkenes and fluoroenynes via cross-coupling reactions using novel multihalogenated vinyl ethers

• Yukiko Karuo,
• Keita Hirata,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2024, 20, 2691–2703, doi:10.3762/bjoc.20.226

• previous study by Thorand [44], we performed the reaction between fluorine-containing vinyl ether 1a and 1.05 equiv of trimethylsilylacetylene (5a) to afford the corresponding enyne 3a in 55% yield (Table 2, entry 1). Cross-coupling utilizing a palladium(II) catalysts containing phosphine ligands produced

Improved deconvolution of natural products’ protein targets using diagnostic ions from chemical proteomics linkers

• Andreas Wiest and
• Pavel Kielkowski

Beilstein J. Org. Chem. 2024, 20, 2323–2341, doi:10.3762/bjoc.20.199

• alkyne probe from the CuAAC reaction mixture or by increasing the concentration of the reducing agent such as tris(2-carboxyethyl)phosphine (TCEP). The reversed chemical proteomics approach in which the azide probe and alkyne tag are used suffers from similar unspecific reactivity of the terminal alkyne

Efficacy of radical reactions of isocyanides with heteroatom radicals in organic synthesis

• Akiya Ogawa and
• Yuki Yamamoto

Beilstein J. Org. Chem. 2024, 20, 2114–2128, doi:10.3762/bjoc.20.182

• interelement compounds such as Ph2P–PPh2 and Ph2P(S) –PPh2 to phenyl isocyanide, but the addition did not proceed at all. This is most likely due to the bulkiness of the Ph2P and Ph2P(S) groups (Scheme 8) [39]. In sharp contrast, the addition of a germyl phosphine (Et2P–GeEt3) to phenyl isocyanide was reported

Development of a flow photochemical process for a π-Lewis acidic metal-catalyzed cyclization/radical addition sequence: in situ-generated 2-benzopyrylium as photoredox catalyst and reactive intermediate

• Masahiro Terada,
• Zen Iwasaki,
• Ryohei Yazaki,
• Shigenobu Umemiya and
• Jun Kikuchi

Beilstein J. Org. Chem. 2024, 20, 1973–1980, doi:10.3762/bjoc.20.173

• moderate yield (entry 1: 42%, cf. batch reaction: 76%). Lowering the reaction temperature to 25 °C reduced the yield (Table 1, entry 2: 35%), but decreasing the amount of the phosphine ligand from 20 mol % to 5 mol % markedly improved the yield (Table 1, entry 3: 53%). Even when the flow rate was increased

Regioselective alkylation of a versatile indazole: Electrophile scope and mechanistic insights from density functional theory calculations

• Pengcheng Lu,
• Luis Juarez,
• Paul A. Wiget,
• Weihe Zhang,
• Krishnan Raman and
• Pravin L. Kotian

Beilstein J. Org. Chem. 2024, 20, 1940–1954, doi:10.3762/bjoc.20.170

• the presence of Cs2CO3. To explore the possibility of N2-selectivity, we hypothesized that the phosphine intermediate of a Mitsunobu reaction could provide chelation control, directing alkylation to the indazole N2-atom while using identical alcohols as described above. Thus, we subjected 6 to simple

Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

• preparing spiro α-methylene-β-lactones from different steroidal propargylic alcohols [13]. The procedure involves a one-pot Pd-catalyzed cyclocarbonylation of alkynols using 5 mol % of Pd(CH3CN)2Cl2 as a catalyst precursor and 30 mol % of 2-(dibutyl)phosphine-1-(2,6-diisopropylphenyl)-1H-imidazole as

• phosphine-based ligand (L). This methodology was applied to the alkynol moiety of ethinylestradiol (8) (86% yield), and alkynols derived from ethisterone, levonorgestrel, lynestrenol, and epiandrosterone (epi-ADT), obtaining excellent yields (85–93%) and high diastereoselectivity (dr > 20:1) in all cases. α

Towards an asymmetric β-selective addition of azlactones to allenoates

• Behzad Nasiri,
• Ghaffar Pasdar,
• Paul Zebrowski,
• Katharina Röser,
• David Naderer and
• Mario Waser

Beilstein J. Org. Chem. 2024, 20, 1504–1509, doi:10.3762/bjoc.20.134

• thus wondering if we could extend this ammonium salt-catalyzed β-selective allenoate functionalization strategy to other amino acid classes. Azlactones 1 have previously been used for γ-selective additions to allenoates under chiral phosphine catalysis [28]. In addition, glycine Schiff base derivatives

Generation of alkyl and acyl radicals by visible-light photoredox catalysis: direct activation of C–O bonds in organic transformations

• Mithu Roy,
• Bitan Sardar,
• Itu Mallick and
• Dipankar Srimani

Beilstein J. Org. Chem. 2024, 20, 1348–1375, doi:10.3762/bjoc.20.119

• [28] introduced the photoredox-catalyzed hydroacylation of styrene derivatives via deoxygenation of challenging aliphatic carboxylic acids (Scheme 1). The deoxygenation was promoted by phosphine reagents to form acyl radicals. The acyl radicals reacted with the C=C bond and formed the expected product

• . Appropriate selection of the phosphine reagent was the key to success in the process. Due to the lower oxidation potential, electron-rich PMe2Ph preferentially transferred a single electron to the excited state of the photocatalyst rather than the alkene, which was essential for obtaining the desired product

• to a phosphine radical cation. The proposed mechanism involves the formation of a phosphine radical cation via SET from photoexcited [Ir(III)] complex. Subsequently, the benzylic alcohol initiates a polar nucleophilic attack on the phosphine radical cation, forming a phosphoranyl radical. This

Manganese-catalyzed C–C and C–N bond formation with alcohols via borrowing hydrogen or hydrogen auto-transfer

• Mohd Farhan Ansari,
• Atul Kumar Maurya,
• Abhishek Kumar and
• Saravanakumar Elangovan

Beilstein J. Org. Chem. 2024, 20, 1111–1166, doi:10.3762/bjoc.20.98

• )phosphine ligand (PN3P) (Mn3) and studied N-methylation reactions in the presence of t-BuOK (20 mol %) at 120 °C for 24 h in toluene [36]. This catalytic system tolerated various functional groups, including nitro, ester, amide, and ketones and gave moderate to good yields (42–98%) of the mono-N-methylated

• condenses with hydrazine followed by reduction and condensation with another aldehyde to afford the N-substituted hydrazones (Scheme 8). Balaraman and co-workers established a phosphine-free manganese catalyst generated in situ from a manganese precursor and a ligand for the N-alkylation of anilines with

•  10). However, sulfonamides with electron-withdrawing groups attached to the aromatic ring (e.g., 4-NO2, 4-CN) were found incompatible with the conditions. Ke and co-workers described an exciting example of a phosphine-free Mn(I)-NHC catalyst for the N-alkylation of amines with alcohols at room

Synthesis of 1,4-azaphosphinine nucleosides and evaluation as inhibitors of human cytidine deaminase and APOBEC3A

• Maksim V. Kvach,
• Stefan Harjes,
• Harikrishnan M. Kurup,
• Geoffrey B. Jameson,
• Elena Harjes and
• Vyacheslav V. Filichev

Beilstein J. Org. Chem. 2024, 20, 1088–1098, doi:10.3762/bjoc.20.96

• basic conditions. Compound 3 was obtained nearly on a 20 g scale in 89% yield after purification by sublimation in vacuo. In the presence of a catalytic amount of AIBN, compound 3 reacted with bis(trimethylsiloxy)phosphine (4) that was prepared in situ [66]. Treatment of the reaction mixture with MeOH

• carrying the β-anomer of Va was detected at the concentration used (20 and 100 µM of inhibitor DNA, 1 mM dC hairpin as a substrate, 600 nM of wild-type A3A containing His6 tag (wtA3A-His6) in 50 mM Na+/K+ phosphate buffer, supplemented with 100 mM NaCl, 1 mM tris(2-carboxyethyl)phosphine (TCEP), 100 µM

Enantioselective synthesis of β-aryl-γ-lactam derivatives via Heck–Matsuda desymmetrization of N-protected 2,5-dihydro-1H-pyrroles

• Arnaldo G. de Oliveira Jr.,
• Martí F. Wang,
• Rafaela C. Carmona,
• Danilo M. Lustosa,
• Sergei A. Gorbatov and
• Carlos R. D. Correia

Beilstein J. Org. Chem. 2024, 20, 940–949, doi:10.3762/bjoc.20.84

• , key five-membered olefins bearing heteroatoms can provide direct access to chiral sulfones, sulfoxides, phosphine oxides [8], phthalides, isochromanones, and lactones [9] in a very efficient and convenient manner. Despite our previous results in this area, the desymmetrization of 2,5-dihydro-1H

Switchable molecular tweezers: design and applications

• Pablo Msellem,
• Maksym Dekthiarenko,
• Nihal Hadj Seyd and
• Guillaume Vives

Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45

• allosteric catalytic regulation (Figure 21). Mirkin and co-workers reported the symmetric tweezers 40 based on a Rh(I) complex with a phosphine and a labile thioether site and Cr(III)–salen arms as catalytic sites for the asymmetric ring opening of cyclohexene oxide by TMSN3 [80]. The closed tweezers showed

• metalloporphyrin arms [83] or larger assemblies [78]. In particular, remarkable double tweezers (or triple-decker catalysts) 41 have been developed (Figure 22). These tweezers consist of two Rh(I) complexes, wherein a catalytically active metal Al(III)–salen arm is shared on the phosphine thioether ligand side

• , and two separate aromatic arms are present on the phosphine ether/amine ligand side [84]. In the closed form, the system is catalytically inactive because the bulky aromatic arms stack with the salen complex and shield its access to the substrate. The addition of Cl− or acetonitrile causes the

Ligand effects, solvent cooperation, and large kinetic solvent deuterium isotope effects in gold(I)-catalyzed intramolecular alkene hydroamination

• Ruichen Lan,
• Brock Yager,
• Yoonsun Jee,
• Cynthia S. Day and
• Amanda C. Jones

Beilstein J. Org. Chem. 2024, 20, 479–496, doi:10.3762/bjoc.20.43

• out under a variety of conditions with cationic gold catalysts supported by phosphine ligands. The impact of ligand on gold, protecting group on nitrogen, and solvent and additive on reaction rates was determined. The most effective reactions utilized more Lewis basic ureas, and more electron

• both within the context of a classic gold π-activation/protodeauration mechanism and a general acid-catalyzed mechanism without intermediate gold alkyls. Keywords: alkene hydroamination; general acid catalysis; gold catalysis; isotope effect; phosphine ligand effect; solvent effect; Introduction

• than those in CD2Cl2). However, this did not hold true uniformly. When a commercially available electron-acceptor ligand known as “Jackiephos” (bis(3,5-bis(trifluoromethyl)phenyl)(2′,4′,6′-triisopropyl-3,6-dimethoxybiphenyl-2-yl)phosphine was used as the AuNTf2 salt (6a), in CD2Cl2, the reaction rate

Mono or double Pd-catalyzed C–H bond functionalization for the annulative π-extension of 1,8-dibromonaphthalene: a one pot access to fluoranthene derivatives

• Nahed Ketata,
• Linhao Liu,
• Ridha Ben Salem and
• Henri Doucet

Beilstein J. Org. Chem. 2024, 20, 427–435, doi:10.3762/bjoc.20.37

• derivatives (Scheme 1b) [21]. In the course of this reaction 20 mol % of Pd catalyst, 50 mol % of phosphine ligand and 30 equiv of DBU as base were used to afford the desired fluoranthene derivatives. 1-Naphthylboronic acid and 1,2-dibromobenzene in the presence of Pd2(dba)3 (20 mol %) and PCy3 (80 mol

Unveiling the regioselectivity of rhodium(I)-catalyzed [2 + 2 + 2] cycloaddition reactions for open-cage C₇₀ production

• Cristina Castanyer,
• Anna Pla-Quintana,
• Anna Roglans,
• Albert Artigas and
• Miquel Solà

Beilstein J. Org. Chem. 2024, 20, 272–279, doi:10.3762/bjoc.20.28

• group was substituted by a mesyl substituent and BIPHEP was used as a model phosphine ligand instead of Tol-BINAP to reduce the computational cost. The calculations, conducted at the B3LYP-D3/cc-pVTZ-PP(SMD=o-DCB)//B3LYP-D3/cc-pVDZ-PP level (see full computational details in Supporting Information File

Using the phospha-Michael reaction for making phosphonium phenolate zwitterions

• Matthias R. Steiner,
• Max Schmallegger,
• Larissa Donner,
• Johann A. Hlina,
• Christoph Marschner,
• Judith Baumgartner and
• Christian Slugovc

Beilstein J. Org. Chem. 2024, 20, 41–51, doi:10.3762/bjoc.20.6

• the mentioned reactions, the first step of the catalytic cycle is the nucleophilic attack of the phosphine on the electrophile, in many cases an electron-deficient olefin. The zwitterion formed from this conjugate addition can subsequently act as a nucleophile or as a base [3][4][5]. The efficiency of

• alkylphosphine, an aldehyde and an alkyne [32]. Another example resulting from phosphine addition to α,β-unsaturated aldehydes was published shortly afterwards [33]. Phosphonium carboxylate zwitterions have been obtained by the reaction of phosphines with acrylic acid [8] and ortho-carboxylated arylphosphines

• 3.09 ppm, respectively, and two novel signals for tertiary butyl groups. Accordingly, we reasoned that the phosphine has reacted presumably with acrylonitrile forming a stable species not suited to catalyze the oxa-Michael reaction. In order to identify this compound, we reacted 1 with acrylonitrile or