Preparation of spirocyclic oxindoles by cyclisation of an oxime to a nitrone and dipolar cycloaddition

• Beth L. Ritchie,
• Alexandra Longcake and
• Iain Coldham

Beilstein J. Org. Chem. 2025, 21, 1890–1896, doi:10.3762/bjoc.21.146

• , 5.4 mmol) and DMAP (132 mg, 1.1 mmol) in CH2Cl2 (45 mL) at room temperature. After 4 d, saturated aqueous NaHCO3 (45 mL) was added and the layers were separated. The organic layer was dried (MgSO4), filtered and evaporated. The residue was purified by column chromatography on silica gel, eluting with

• , dimethyl sulphide (51.3 mL, 693 mmol) was added, and the mixture was warmed to room temperature and stirred. After 16 h, the solvent was evaporated and the residue was purified by column chromatography on silica gel, eluting with EtOAc/petrol 1:1. The product was recrystallised from n-hexane/CH2Cl2 to give

• -methylmaleimide (255 mg, 2.30 mmol) was added and the mixture was heated under reflux. After 3 h, further N-methylmaleimide (128 mg, 1.84 mmol) was added, and the mixture was heated under reflux for a further 1 h. The mixture was cooled to room temperature and the solvent was evaporated. The crude product

Chiral phosphoric acid-catalyzed asymmetric synthesis of helically chiral, planarly chiral and inherently chiral molecules

• Wei Liu and
• Xiaoyu Yang

Beilstein J. Org. Chem. 2025, 21, 1864–1889, doi:10.3762/bjoc.21.145

• enantioselective synthesis of planarly chiral macrocycles through a dynamic kinetic resolution approach [15]. Despite bearing an amino group on the phenyl ring, the configuration of the macrocyclic paracyclophane 32 was found to be unstable at room temperature. Consequently, by employing a CPA-catalyzed asymmetric

Photoswitches beyond azobenzene: a beginner’s guide

• Michela Marcon,
• Christoph Haag and
• Burkhard König

Beilstein J. Org. Chem. 2025, 21, 1808–1853, doi:10.3762/bjoc.21.143

• with a photoswitch, several factors must be considered: substituents, temperature, and solvent strongly affect the photophysical properties. For instance, the presence of electron-withdrawing (for instance -Cl, -Br, -CN, -NO2) and electron-donating groups (-alkyl, -OR, -NR2), which are directly

• the time within 50% of the metastable isomer is thermally converted to the stable one [3]. It depends on the photoswitch class, solvent, substitution pattern, and temperature. For some photoswitch classes, proton exchange and intramolecular hydrogen bonds are known to accelerate the thermal relaxation

Fe-catalyzed efficient synthesis of 2,4- and 4-substituted quinolines via C(sp²)–C(sp²) bond scission of styrenes

• Prafull A. Jagtap,
• Manish M. Petkar,
• Vaishnavi R. Sawant and
• Bhalchandra M. Bhanage

Beilstein J. Org. Chem. 2025, 21, 1799–1807, doi:10.3762/bjoc.21.142

• observed when the amount of trifluoroacetic acid (TFA) was reduced from 1.5 equiv to 1.0 equiv (Table 1, entry 12). Consequently, in the absence of the additive, the yield was significantly diminished due to the incomplete consumption of 1a (Table 1, entry 13). Lowering the temperature to 100 °C

• 26% yield. Then, in reaction 3, a one-pot, two-step reaction involving phenylglyoxalic acid (2aa) was carried out. In step 1, compounds 1a and 2aa were stirred at room temperature for 5 minutes in the presence of a catalyst and an additive. Subsequently, in step 2, styrene (2a) was added, and the

Research progress on calixarene/pillararene-based controlled drug release systems

• Liu-Huan Yi,
• Jian Qin,
• Si-Ran Lu,
• Liu-Pan Yang,
• Li-Li Wang and
• Huan Yao

Beilstein J. Org. Chem. 2025, 21, 1757–1785, doi:10.3762/bjoc.21.139

• times. This bis-vesicle structure possesses the following intelligent responsive characteristics: (1) temperature sensitivity originating from the enthalpy-driven nature of the host–guest interaction; (2) redox responsiveness due to the reversible electron transfer of MVC12; (3) competitive complexation

• making the system sensitive to cyclodextrins. Experiments have confirmed that this carrier can efficiently encapsulate DOX and trigger drug release through multiple stimuli, demonstrating good potential for anticancer therapy in vitro. This intelligent delivery system, integrating temperature, redox, and

• binary vesicle system based on WP6 and SAINT molecules (G5), which exhibits multiple stimulus-responsive characteristics to pH, Ca2+ and temperature (Figure 20). WP6 and G5, as amphiphilic molecules containing pyridine groups and alkyl chains, form supramolecular amphiphiles through host−guest

Unique halogen–π association detected in single crystals of C–N atropisomeric N-(2-halophenyl)quinolin-2-one derivatives and the thione analogue

• Mai Uchibori,
• Nanami Murate,
• Kanako Shima,
• Tatsunori Sakagami,
• Ko Kanehisa,
• Gary James Richards,
• Akiko Hori and
• Osamu Kitagawa

Beilstein J. Org. Chem. 2025, 21, 1748–1756, doi:10.3762/bjoc.21.138

• vapour diffusion of hexane into a methanol solution of the compound at room temperature) and their X-ray crystal structural analyses were performed (Figure 2) [33]. In the crystals of rac-1a, a π-type intermolecular interaction between the bromine atom and the benzene ring of the quinolinone was found

• observed in the crystals of optically pure forms (P)-1a,b (Figure 3, single crystals of (P)-1a,b were obtained by vapour diffusion of hexane into a methanol solution of the compound at room temperature) [34]. Meanwhile, the halogen atoms in (P)-1a,b were found to interact with the C4 atom on the lactam

• racemic quinolinones rac-1 in Figure 2 (single crystals of rac-2a were obtained from slow evaporation of hexane/methanol (1:1) mixture at room temperature) [37]. That is, in contrast to rac-1, in which homochiral layered polymer chains were formed, crystallization of quinoline-2-thione rac-2a led to the

Convenient alternative synthesis of the Malassezia-derived virulence factor malassezione and related compounds

• Karu Ramesh and
• Stephen L. Bearne

Beilstein J. Org. Chem. 2025, 21, 1730–1736, doi:10.3762/bjoc.21.135

• are uncorrected. tert-Butyl 3-(2-methoxy-2-oxoethyl)-1H-indole-1-carboxylate (21). A solution of indol-3-yl acetic acid (20, 5.1 g, 29.0 mmol, 1.0 equiv) in dry MeOH (200 mL) was cooled to 0 °C, and SOCl2 (10.5 mL, 145 mmol, 5.0 equiv) was added slowly. After stirring for 12 h at room temperature, the

• DMAP (0.63 g, 5.2 mmol, 0.2 equiv) were added [32]. The mixture was stirred for 2 h at room temperature after which the solvent was removed under reduced pressure. The residue was dissolved in EtOAc (250 mL) and subsequently washed with saturated aqueous NH4Cl (150 mL), saturated aqueous NaHCO3 (150 mL

• , 3 equiv) in H2O (250 mL) was added to a solution of 21 (5.0 g, 17.2 mmol, 1.0 equiv) in THF (300 mL) and MeOH (150 mL). After stirring for 18 h at room temperature, the mixture was concentrated in vacuo and a 10% aqueous solution of citric acid (100 mL) was added. The aqueous layer was extracted

3,3'-Linked BINOL macrocycles: optimized synthesis of crown ethers featuring one or two BINOL units

• Somayyeh Kheirjou,
• Jan Riebe,
• Maike Thiele,
• Christoph Wölper and
• Jochen Niemeyer

Beilstein J. Org. Chem. 2025, 21, 1719–1729, doi:10.3762/bjoc.21.134

• (69/61/72% over two steps, see Figure 6). However, only if temperature and reaction times in this step were carefully controlled, the reaction proceeded cleanly. Deviations from the optimized conditions (see Supporting Information File 1 for details) resulted in greatly diminished yields due to the

Approaches to stereoselective 1,1'-glycosylation

• Daniele Zucchetta and
• Alla Zamyatina

Beilstein J. Org. Chem. 2025, 21, 1700–1718, doi:10.3762/bjoc.21.133

• diminish the reactivity of N-Troc-protected GlcN-derived donors [72]. Indeed, the presence of an electron-withdrawing group at position 3 of the GlcN-derived donor 70 merely required an elevated reaction temperature (0 °C), in contrast to the conditions used for the 3-O-Nap-protected GalN-based donor 68

• (reaction temperature −60 °C). Permanent ether-type protecting groups, such as benzyl, or those that require harsh acidic or basic conditions for removal, are often incompatible with the labile functional groups present in complex biomolecules derived from synthetic nonreducing disaccharides. To address

• reduced reaction temperatures (−20 to −60 °C), N-phenyl trifluoroacetimidate (PTFA) donors are sufficiently stable to be used in glycosylation reactions at 0 °C or ambient temperature, while remaining reactive enough to glycosylate conformationally hindered nucleophiles in the presence of catalytic TMSOTf

Continuous-flow-enabled intensification in nitration processes: a review of technological developments and practical applications over the past decade

• Feng Zhou,
• Chuansong Duanmu,
• Yanxing Li,
• Jin Li,
• Haiqing Xu,
• Pan Wang and
• Kai Zhu

Beilstein J. Org. Chem. 2025, 21, 1678–1699, doi:10.3762/bjoc.21.132

• /selectivity through optimized parameters (microwave energy, temperature, feed composition) [11]. Recent years have witnessed growing adoption of the continuous-flow technology in nitration processes across laboratory and industrial scales, driven by the reaction's classification as a highly hazardous chemical

• reactors. For intensely exothermic nitration reactions with rapid kinetics, this technology enables uniform mixing, efficient heat removal, and precise control of critical parameters including reaction temperature and reactant stoichiometry. Crucially, continuous operation permits scalable production of

• generated during the dilution process. While many nitration processes usually exhibit rapid kinetics, specific transformations like partial dinitration reactions demonstrate notably slower reaction rates, substantially compromising process throughput. Although thermal activation via temperature elevation

Structural analysis of stereoselective galactose pyruvylation toward the synthesis of bacterial capsular polysaccharides

• Tsun-Yi Chiang,
• Mei-Huei Lin,
• Chun-Wei Chang,
• Jinq-Chyi Lee and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2025, 21, 1671–1677, doi:10.3762/bjoc.21.131

• function. Careful manipulation of reaction conditions such as solvent and temperature is necessary to achieve sufficient diastereomeric purity in pyruvate modification. This research contributes to the development in the field of polysaccharide synthesis and draws upon established methodologies, reflecting

Influence of the cation in hypophosphite-mediated catalyst-free reductive amination

• Natalia Lebedeva,
• Fedor Kliuev,
• Olesya Zvereva,
• Klim Biriukov,
• Evgeniya Podyacheva,
• Maria Godovikova,
• Oleg I. Afanasyev and
• Denis Chusov

Beilstein J. Org. Chem. 2025, 21, 1661–1670, doi:10.3762/bjoc.21.130

• the further study. Using the optimal K2CO3/H3PO2 ratio 0.125/0.5, it was found that 78% yield of the model amine could be reached at lower temperature (110 °C) under prolonged reaction time (Scheme 2). The water content in the system had a crucial influence on the reaction outcome: an excess of the

Synthesis of optically active folded cyclic dimers and trimers

• Ena Kumamoto,
• Kana Ogawa,
• Kazunori Okamoto and
• Yasuhiro Morisaki

Beilstein J. Org. Chem. 2025, 21, 1603–1612, doi:10.3762/bjoc.21.124

• samples were analyzed in CHCl3 at room temperature. Photoluminescence (PL) spectra were recorded on a JASCO FP-8500 spectrofluorometer, and samples were analyzed in CHCl3 at room temperature. Absolute PL quantum efficiency was calculated on a JASCO FP-8500 with an ILF-835 integrating sphere. The PL

• with CHCl3 as a solvent at room temperature. Circularly polarized luminescence (CPL) spectra were recorded on a JASCO CPL-300 with CHCl3 as a solvent at room temperature. Materials Commercially available compounds used without purification are as follows: Pd2(dba)3, SPhos (2-dicyclohexylphosphino-2',6

• mmol), Pd2(dba)3 (6.1 mg, 0.0067 mmol), SPhos (5.6 mg, 0.014 mmol), CuI (1.8 mg, 0.0095 mmol), toluene (40 mL) and Et3N (40 mL) was placed in a round-bottom flask equipped with a magnetic stirring bar. After degassing the reaction mixture several times, the mixture was heated at reflux temperature for

3-Aryl-2H-azirines as annulation reagents in the Ni(II)-catalyzed synthesis of 1H-benzo[4,5]thieno[3,2-b]pyrroles

• Julia I. Pavlenko,
• Pavel A. Sakharov,
• Anastasiya V. Agafonova,
• Derenik A. Isadzhanyan,
• Alexander F. Khlebnikov and
• Mikhail S. Novikov

Beilstein J. Org. Chem. 2025, 21, 1595–1602, doi:10.3762/bjoc.21.123

• reaction. The highest yield of 3a (85%) was achieved by treating 1 with 3.2 equiv of the azirine in MeOH at 100 °С with 50 mol % of Ni(hfacac)2 (Table 1, entry 13). Lowering the temperature and the catalyst loading resulted in a slight deterioration in the yield and a significant slowing of the reaction

Chemical synthesis of glycan motifs from the antitumor agent PI-88 through an orthogonal one-pot glycosylation strategy

• Shaokang Yang,
• Xingchun Sun,
• Hanyingzi Fan and
• Guozhi Xiao

Beilstein J. Org. Chem. 2025, 21, 1587–1594, doi:10.3762/bjoc.21.122

• in mannosyl PVB 8 (1.0 equiv) in the presence of TMSOTf as catalyst proceeded smoothly at 0 °C to room temperature, affording the α-Man-(1→3)-Man PVB disaccharide. The further coupling of the above PVB disaccharide with the poorly reactive 2-OH in mannoside 9 (0.9 equiv) under activation with NIS and

• TMSOTf at 0 °C to room temperature, successfully furnished the desired α-Man-(1→3)-α-Man-(1→3)-α-Man trisaccharide 10 in 87% yield in a one pot manner. Removal of TBDPS group in 10 with 70% HF·pyridine and subsequent phosphitylation of the resulting free alcohol with phosphoramidite 11 provided the

• all Bz groups with 1 M NaOH (dioxane/MeOH/H2O, room temperature). The monophosphorylated trisaccharide 1 was obtained in 60% overall yield over two steps from 12 after purification over a SephadexTM LH-20 column. It was noted that the switch of deprotection sequences (first Bz groups, second Bn and

Thermodynamic equilibrium between locally excited and charge transfer states in perylene–phenothiazine dyads

• Issei Fukunaga,
• Shunsuke Kobashi,
• Yuki Nagai,
• Hiroki Horita,
• Hiromitsu Maeda and
• Yoichi Kobayashi

Beilstein J. Org. Chem. 2025, 21, 1577–1586, doi:10.3762/bjoc.21.121

• -carborane exhibit such behavior, where LE and CT states dynamically interconvert depending on solvent polarity and temperature [10][11][12]. When the interconversion is faster than radiative decay, the two states can reach thermodynamic equilibrium, and their relative populations are determined by the

• the degree of electronic interaction between the donor PTZ and acceptor Pe moieties, as indicated by the decreased overlap between HOMO and LUMO. UV–vis absorption spectra of the Pe–PTZ derivatives were recorded in benzene at room temperature (Figure 3a). All compounds exhibited characteristic

• phenothiazine derivative, 12-phenyl-12H-benzo[a]phenothiazine, in toluene at room temperature has been estimated to be 28 ps (with an additional minor 0.7 ps component attributed to small-scale structural changes) [17]. It is also noted that the relaxation dynamics depend on the molecular structure and the

pH-Controlled isomerization kinetics of ortho-disubstituted benzamidines: E/Z isomerism and axial chirality

• Ryota Kimura,
• Satoshi Ichikawa and
• Akira Katsuyama

Beilstein J. Org. Chem. 2025, 21, 1568–1576, doi:10.3762/bjoc.21.120

• bond rotation was investigated by variable temperature nuclear magnetic resonance (VT-NMR) spectra (Figure 3) in DMSO-d6 [27]. In the case of the molecular form of amidine 1 (Figure 3a), the signals corresponding to the two methyl groups resulting from the amidine E/Z isomerism were observed separately

• at 313 K (1.17 and 0.95 ppm), and they gradually fused as the temperature increased. The activation energy of E/Z isomerization was calculated to be 77 kJ·mol−1 from the observed coalescence temperature (Tc = 378 K). On the other hand, the two methyl signals of amidine 1 trifluoroacetate salt were

• . Notably, at pH 9.2, racemization proceeded minimally, even under high temperature conditions. Furthermore, it was confirmed that racemization requires a higher pH where a higher proportion of the amidine exists in its molecular form. This result was consistent with our DFT calculations, which showed that

Synthesis of an aza[5]helicene-incorporated macrocyclic heteroarene via oxidation of an o-phenylene-pyrrole-thiophene icosamer

• Yusuke Matsuo,
• Aoi Nakagawa,
• Shu Seki and
• Takayuki Tanaka

Beilstein J. Org. Chem. 2025, 21, 1561–1567, doi:10.3762/bjoc.21.119

• acyclic heteroaromatics [26][27]. Thus, to a solution of 4 in CH2Cl2 was added 15 equivalents of PIFA at −78 °C and stirred for 3 h. The mixture was then allowed to warm to room temperature to give a dark solution. The system was worked-up with NaBH4/MeOH for 10 minutes followed by extraction with CH2Cl2

• and evaporation of the solvent to afford a crude product, which was recrystallized from THF to give 5 in 58% yield. Due to its poor solubility in common organic solvents, the 1H NMR spectrum could only be recorded in DMSO. At room temperature, the 1H NMR spectrum in DMSO-d6 exhibited broad signals in

• at 399 nm (Figure 5b). A broad emission was observed at 528 nm, resulting in a relatively large Stokes shift of 6100 cm−1, which can be attributed to the structural relaxation in the excited state, as inferred by the observed broad 1H NMR spectrum at room temperature. Due to the thermal energy loss

Facile synthesis of hydantoin/1,2,4-oxadiazoline spiro-compounds via 1,3-dipolar cycloaddition of nitrile oxides to 5-iminohydantoins

• Juliana V. Petrova,
• Varvara T. Tkachenko,
• Victor A. Tafeenko,
• Anna S. Pestretsova,
• Vadim S. Pokrovsky,
• Maxim E. Kukushkin and
• Elena K. Beloglazkina

Beilstein J. Org. Chem. 2025, 21, 1552–1560, doi:10.3762/bjoc.21.118

• dipolarophiles into the 32CA, it is reasonable to utilize conditions that minimize the side reactions of the dipole. This could include lowering the temperature [32] and slowly adding a base [33]. In this work we have tested two alternative techniques for the dipolar cycloaddition. In the first method, a

• ]. The most dramatic discrepancy in spiro-compound yields was observed during the reaction with this nitrile oxide, suggesting that classical conditions (low temperature and inert atmosphere) may prove more fruitful in preventing the degradation of the dipole. The influence of the concentration of the

• decomposing even at room temperature. Taking these into account, we have synthesized compound 5c using an alternative route starting from the chloro oxime 4a and 5-iminothiohydantoin 2j (Scheme 4), obtained similarly to other dipolarophiles [22]. The total yield of the product 5c in this case turned out to be

Azide–alkyne cycloaddition (click) reaction in biomass-derived solvent Cyrene^TM under one-pot conditions

• Zoltán Medgyesi and
• László T. Mika

Beilstein J. Org. Chem. 2025, 21, 1544–1551, doi:10.3762/bjoc.21.117

• capillary column (15 m × 0.25 mm × 0.25 µm) using H2 as a carrier gas. For the analysis, 10 μL of the reaction mixture was dissolved in 1 mL of ethyl acetate, followed by adding 10 μL toluene as the internal standard. Heating profile of GC–FID analysis: The initial temperature was 100 °C and was hold for

• 0.5 min. Heating rate: 40 °C/min up to the final temperature of 270 °C. The final temperature was held for 4.25 min. The water content of CyreneTM was measured on a Methrom 684 KF Coulometer at Balint Analitika Ltd, Budapest, Hungary. CyreneTM was purchased from Sigma-Aldrich Kft. Budapest, Hungary

• , and 0.01 mmol CuI, were dissolved in 2.5 mL CyreneTM. The reaction mixture was stirred overnight at a given temperature. After the reaction, 20 mL of cold distilled water was added, followed by intensive stirring. The solid product was filtered, washed with distilled water (3 × 5 mL), and dried until

General method for the synthesis of enaminones via photocatalysis

• Paula Pérez-Ramos,
• Raquel G. Soengas and
• Humberto Rodríguez-Solla

Beilstein J. Org. Chem. 2025, 21, 1535–1543, doi:10.3762/bjoc.21.116

• by DME, DMSO or acetone diminished the product yields (Table 1, entries 7–9). The reactivity of acridinium PC1 was superior to that of other photocatalysts, including 4-CzlPN (PC2) and [Ir(dF(CF3)ppy)2(dtbbpy)]PF6 (PC3) (Table 1, entries 10 and 11). Attempts to increase the temperature of the process

Azobenzene protonation as a tool for temperature sensing

• Antti Siiskonen,
• Sami Vesamäki and
• Arri Priimagi

Beilstein J. Org. Chem. 2025, 21, 1528–1534, doi:10.3762/bjoc.21.115

• changes in their absorption and photochemical properties. While azobenzene protonation has been recently used as a tool in photoswitching studies, the factors influencing protonation itself have received little attention. Here, we report a strong temperature dependence of azobenzene protonation in 1,2

• -dichloroethane and highlight its potential for temperature sensing applications. Density functional theory calculations were performed to support our findings and to investigate the mechanisms of azobenzene–acid interactions, aiming to guide the design of azobenzene-based temperature sensors in future research

• . Keywords: azobenzene; protonation; sensing; spectral changes; temperature; Introduction Molecular switches are molecules that can reversibly shift between distinct (meta)stable states in response to external stimuli such as light, pH changes, or electric fields [1]. Over the past decades, they have

Calcium waste as a catalyst in the transesterification for demanding esters: scalability perspective

• Anton N. Potorochenko and
• Konstantin S. Rodygin

Beilstein J. Org. Chem. 2025, 21, 1520–1527, doi:10.3762/bjoc.21.114

• % yields, respectively. The transesterification of soybean oil (1a) with methanol (2a) was carried out as a gram-scale batch reaction using 21 g of soybean oil, 210 mg of catalyst (1 wt %), and 11.7 mL of methanol (Scheme 3). The temperature and reaction time conditions used were the same as in the

Ambident reactivity of enolizable 5-mercapto-1H-tetrazoles in trapping reactions with in situ-generated thiocarbonyl S-methanides derived from sterically crowded cycloaliphatic thioketones

• Grzegorz Mlostoń,
• Małgorzata Celeda,
• Marcin Palusiak,
• Heinz Heimgartner,
• Marta Denel-Bobrowska and
• Agnieszka B. Olejniczak

Beilstein J. Org. Chem. 2025, 21, 1508–1519, doi:10.3762/bjoc.21.113

• slightly higher temperature (60 °C). In both cases, evolution of nitrogen was completed after ca. 3 h and pure thiiranes 8a and 8b were isolated as sole products in 62%, and 58% yield, respectively (Scheme 4). Thus, their formation clearly evidenced formation of the respective thiocarbonyl S-methanides 1c

• stable 9 into the more stable 10 was observed in some cases (derived from 1c) in the CDCl3 solution at room temperature. Therefore, it seems likely that the first step of the reaction is the N–H insertion process. The compositions of the obtained crude mixtures suggest that the final addition step

• the sterically most hindered dispiro-cyclohexyl-substituted thiocarbonyl S-methanide 2d. Notably, in some cases spontaneous isomerization of the generally less stable thioaminals 9 in CDCl3 solution at room temperature was also observed. It seems likely that this isomerization follows an

Highly distinguishable isomeric states of a tripodal arylazopyrazole derivative on graphite through electron/hole-induced switching at ambient conditions

• Himani Malik,
• Sudha Devi,
• Debapriya Gupta,
• Ankit Kumar Gaur,
• Sugumar Venkataramani and
• Thiruvancheril G. Gopakumar

Beilstein J. Org. Chem. 2025, 21, 1496–1507, doi:10.3762/bjoc.21.112

• isomer of azobenzene (AB) is a few days. Arylazopyrazole-based molecular switches are one of the profoundly explored systems in recent times due to their superior bidirectional photoswitching and long half-life (over a thousand days at room temperature) of Z isomers. Herein, we utilize an efficient solid

• experimental conditions. The choice of molecules that can be studied under ultra-high vacuum (UHV) is limited due to the requirement of their thermal stability and UHV compatible sublimation temperature. Therefore, the solution-based preparation method and solid-state measurements at ambient conditions hold

• barrier and the long lifetime of the non-equilibrium states are at the origin of their remarkable stability at room temperature. The remarkable stability of the states at ambient conditions provides an opportunity to use a single FNAAP molecule as an 8-bit operation. We propose to switch the molecule