Synthesis of photo- and ionochromic N-acylated 2-(aminomethylene)benzo[b]thiophene-3(2Н)-ones with a terminal phenanthroline group

• Vladimir P. Rybalkin,
• Sofiya Yu. Zmeeva,
• Lidiya L. Popova,
• Irina V. Dubonosova,
• Olga Yu. Karlutova,
• Oleg P. Demidov,
• Alexander D. Dubonosov and
• Vladimir A. Bren

Beilstein J. Org. Chem. 2024, 20, 552–560, doi:10.3762/bjoc.20.47

• a terminal phenanthroline receptor substituent was synthesized. Upon irradiation in acetonitrile or DMSO with light of 436 nm, they underwent Z–E isomerization of the C=C bond, followed by very fast N→O migration of the acyl group and the formation of nonemissive O-acylated isomers. These isomers

• sequential addition of Fe2+ and AcO−, we synthesized N-acylated 2-(aminomethylene)benzo[b]thiophene-3(2Н)-ones with a terminal phenanthroline substituent and studied the spectral-luminescent, photochromic and ionochromic properties. The phenanthroline moiety was incorporated into the molecule due to the

• ]thiophene-3(2Н)-ones 2a–c with a terminal phenanthroline substituent was (E)-2-(((1,10-phenanthrolin-5-yl)amino)methylene)benzo[b]thiophen-3(2H)-one (1), obtained by condensation of 3-hydroxybenzo[b]thiophene-2-carbaldehyde with 5-aminophenanthroline in acetonitrile (Scheme 1). (Z)-N-((3-Oxobenzo[b]thiophen

Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

• Michio Yamada

Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13

• -phenanthroline-based rotaxane 50 by employing the [2 + 2] CA–RE reaction, as shown in Scheme 17 [123]. The initial threading reaction involving the rod molecule 47 and macrocycle 48, constructed using [Cu(MeCN)4]PF6, resulted in the formation of the pseudorotaxane 49. The ensuing [2 + 2] CA–RE reaction of 49

• room-temperature solution (dichloromethane) and as a frozen matrix at 77 K [123]. This is in contrast with the typical homoleptic phenanthroline-based CuI complexes renowned for their emissions from a triplet metal-to-ligand charge transfer excited state. The absence of luminescence may be attributed

Selectivity control towards CO versus H₂ for photo-driven CO₂ reduction with a novel Co(II) catalyst

• Lisa-Lou Gracia,
• Philip Henkel,
• Olaf Fuhr and
• Claudia Bizzarri

Beilstein J. Org. Chem. 2023, 19, 1766–1775, doi:10.3762/bjoc.19.129

• interested in the development of earth-abundant systems. In particular, we chose the heteroleptic complex [Cu(dmp)DPEPhos](BF4), where dmp is 2,9-dimethyl-1,10-phenanthroline and DPEPhos is bis[(2-diphenylphosphino)phenyl] ether, which had been already successfully employed in other artificial photosynthesis

Application of N-heterocyclic carbene–Cu(I) complexes as catalysts in organic synthesis: a review

• Nosheen Beig,
• Varsha Goyal and
• Raj K. Bansal

Beilstein J. Org. Chem. 2023, 19, 1408–1442, doi:10.3762/bjoc.19.102

• -donors on the catalytic activity of NHC–Cu(I) complexes for azide–alkyne [3 + 2] cycloaddition reactions [67]. They determined binding constants of four NHC–CuCl complexes with two N-donors, which revealed that addition of phenanthroline to the NHC–CuCl enhanced the catalytic activity manifold. In fact

• , on using [(SIMes)CuCl] with 1 mol % of phenanthroline for the [3 + 2] cycloaddition of benzyl azide with phenylacetylene, the yield of the product was 78% as against 10% in the absence of the N-donor (Scheme 49). Overall, two catalytic combinations 130a,b were found to give the best results. Cazin

Pyridine C(sp²)–H bond functionalization under transition-metal and rare earth metal catalysis

• Haritha Sindhe,
• Malladi Mounika Reddy,
• Karthikeyan Rajkumar,
• Akshay Kamble,
• Amardeep Singh,
• Anand Kumar and
• Satyasheel Sharma

Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62

• strong coordination of the pyridyl N-atom with Pd in the presence of a bidentate ligand was reported by Yu and co-workers [83]. They showcased the C3-selective olefination of pyridines using 1,10-phenanthroline, a bis-dentate ligand that weakens the coordination of the Pd catalyst with the pyridyl N-atom

• groups used Pd(OAc)2 as catalyst with 1,10-phenanthroline as ligand. The group of Yu used aryl halides 137 as coupling partner, whereas the group of Tan utilized aryl tosylates 142 as coupling partner (Scheme 26). The Yu group also applied the developed protocol for the synthesis of the drug molecule

• product 172 releasing a Rh(I) species. The Rh(III) species is regenerated in the presence of the copper salt. In another case of C3-(hetero)arylation, Yu and group [104] using palladium for C–H activation of pyridine with phenanthroline as a ligand developed a method in 2016 (Scheme 34). The authors

A new route for the synthesis of 1-deazaguanine and 1-deazahypoxanthine

• Raphael Bereiter,
• Marco Oberlechner and
• Ronald Micura

Beilstein J. Org. Chem. 2022, 18, 1617–1624, doi:10.3762/bjoc.18.172

• 3,4-dihydropyran in dimethylformamide to obtain the corresponding tetrahydropyranyl-protected amine 17. Subsequently, a copper-catalyzed C–O bond formation at C6 using benzyl alcohol in the presence of caesium carbonate, copper(I) iodide, and 1,10-phenanthroline furnished benzyl ether 18 in excellent

• -(tetrahydro-2H-pyran-2-yl)-1-deazapurine (18) Compound 17 (1.72 g, 5.23 mmol), copper(I) iodide (CuI, 99.52 mg, 0.52 mmol), 1,10-phenanthroline (188.35 mg, 1.05 mmol), caesium carbonate (Cs2CO3, 2.38 g, 7.32 mmol) and benzyl alcohol (BnOH, 1.13 g, 1.07 mL, 10.45 mmol) were suspended in 2.62 mL toluene (0.5 mL

• )), 154.08 (H-C(2)), 162.52 (H-C(6)); ESIMS (m/z): [M + H]+ calcd for 151.06; found, 151.06. O6-Benzyl-1-deazahypoxanthine (31) Compound 17 (500 mg, 1.52 mmol), copper(I) iodide (CuI, 28.93 mg, 152 µmol), 1,10-phenanthroline (54.75 mg, 304 µmol), caesium carbonate (Cs2CO3, 692.93 mg, 2.13 mmol) and benzyl

Synthesis of N-phenyl- and N-thiazolyl-1H-indazoles by copper-catalyzed intramolecular N-arylation of ortho-chlorinated arylhydrazones

• Yara Cristina Marchioro Barbosa,
• Guilherme Caneppele Paveglio,
• Claudio Martin Pereira de Pereira,
• Sidnei Moura,
• Cristiane Storck Schwalm,
• Gleison Antonio Casagrande and
• Lucas Pizzuti

Beilstein J. Org. Chem. 2022, 18, 1079–1087, doi:10.3762/bjoc.18.110

• '-dimethylethanolamine (DMEA) and trans-1,2-diaminocyclohexane (DACH) were evaluated as ligands (Table 1, entries 18 and 19). However, the yield was lower compared to that obtained with 1,10-phenanthroline (phen). Control experiments were performed without catalyst (Table 1, entry 20), base (Table 1, entry 21), or

Synthesis of novel alkynyl imidazopyridinyl selenides: copper-catalyzed tandem selenation of selenium with 2-arylimidazo[1,2-a]pyridines and terminal alkynes

• Mio Matsumura,
• Kaho Tsukada,
• Kiwa Sugimoto,
• Yuki Murata and
• Shuji Yasuike

Beilstein J. Org. Chem. 2022, 18, 863–871, doi:10.3762/bjoc.18.87

• reaction between terminal alkynes and diimidazopyridinyl diselenides, generated from imidazo[1,2-a]pyridines and Se powder, using 10 mol % of CuI and 1,10-phenanthroline as the catalytic system under aerobic conditions. The C(sp2)–Se and C(sp)–Se bond-formation reaction can be performed in one-pot by using

• ]. Guo, Han and Ma et al. also performed the synthesis of aryl imidazopyridinyl selenides in the presence of Ag2CO3 (2 equiv) and Cs2CO3 (2 equiv) using the CuI/1,10-phenanthroline catalytic system by replacing the aryl group donor with arylboronic acids [23]. Zhou et al. reported the reaction of Se

• or dialkyl diselenides, followed by C–H selenation with imidazopyridines to form the corresponding compounds. We also reported the one-pot two-step reaction of Se powder with imidazopyridine and triarylbismuthines using the CuI/1,10-phenanthroline catalytic system without bases, which formed similar

Heteroleptic metallosupramolecular aggregates/complexation for supramolecular catalysis

• Prodip Howlader and
• Michael Schmittel

Beilstein J. Org. Chem. 2022, 18, 597–630, doi:10.3762/bjoc.18.62

• procedure developed by Sauvage on the basis of topological control [33] has found ample use in the preparation of rotaxane-based machines and devices [34]. A key element is a macrocyclic phenanthroline with an endotopic binding site as it precludes homoleptic complex formation. A further principle

• PYridine and Phenanthroline complexes [85][86]), HETPHEN (HETeroleptic bisPHENanthroline complexes [87]) and HETTAP (HETeroleptic Terpyridine And Phenanthroline complexes [88]) interactions (Figure 12). Due to the different amount of donor atoms about the metal ion, the binding strength will decrease in

• activity [94] (Figure 14). Because in any moment of the rotation there should at least one copper(I) phenanthroline be freed from contact with the monodentate rotator X, one would expect that the temporarily exposed copper(I) ions are catalytically active. It is important to note that this copper ion due

BINOL as a chiral element in mechanically interlocked molecules

• Matthias Krajnc and
• Jochen Niemeyer

Beilstein J. Org. Chem. 2022, 18, 508–523, doi:10.3762/bjoc.18.53

• ]. The template complex (S)-3 was assembled by mixing the macrocycle (S)-1 (containing both a phenanthroline ligand and a BINOL unit) with [Cu(CH3CN4)]PF6 and the acyclic phenanthroline precursor 2. Then, the BINOL-based diiodide (S)-4 and Cs2CO3 were added successively over 18 hours. This resulted in

• . Accordingly, demetalation leads to an almost complete disappearance of the CD signals in this area (see Figure 2). Saito and coworkers demonstrated that the homochiral [2]rotaxane (R)-10 can be efficiently synthesized using an active metal template approach [44][45]. The macrocyclic phenanthroline (R)-7 was

• treated with copper iodide to obtain the phenanthroline–Cu(I) complex (R)-8. A Glaser-type coupling with the terminal alkynes 9, followed by demetalation, proceeds smoothly in 78% yield. This furnishes the desired chiral rotaxane (R)-10, consisting of a BINOL-based macrocycle and a diyne thread. The CD

Recent developments and trends in the iron- and cobalt-catalyzed Sonogashira reactions

• Surendran Amrutha,
• Sankaran Radhika and
• Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 262–285, doi:10.3762/bjoc.18.31

• steric effects. Anilkumar and co-workers reported an iron-catalyzed Sonogashira coupling of aryl iodides with terminal alkynes in the presence of a catalytic system made up of the greenest solvent, water, in the presence of 10 mol % FeCl3·6H2O and 20 mol % 1,10-phenanthroline as ligand under aerobic

• , but their efficiencies were found to be lower than that of 1,10-phenanthroline. Metal impurities in FeCl3·6H2O were detected by using ICP mass spectrometry. Lipshutz and co-workers prepared nanoparticles from inexpensive iron(III) chloride containing reusable palladium in ppm level and XPhoS as ligand

• synthesized 2-arylbenzo[b]furans by intramolecular arylation and Sonogashira cross-coupling of o-iodophenol with phenylacetylene/1-substituted-2-trimethylsilylacetylene under iron(III) catalysis in the presence of 5 mol % 1,10-phenanthroline as ligand and Cs2CO3 as base (Scheme 14) [31]. The use of 1,10

Iron-catalyzed domino coupling reactions of π-systems

• Austin Pounder and
• William Tam

Beilstein J. Org. Chem. 2021, 17, 2848–2893, doi:10.3762/bjoc.17.196

Visible-light-mediated copper photocatalysis for organic syntheses

• Yajing Zhang,
• Qian Wang,
• Zongsheng Yan,
• Donglai Ma and
• Yuguang Zheng

Beilstein J. Org. Chem. 2021, 17, 2520–2542, doi:10.3762/bjoc.17.169

• cooperative steric hindrance based on bulky substituents at the 2,9-position of the phenanthroline moiety [32][33]. Alternatively, heteroleptic CuI complexes with phenanthroline and bulky chelating phosphine ligands were also synthesized [30][34][35]. The photophysical properties are dramatically modified by

• studies included visible-light catalysis. In 2012, Reiser’s group [44] reported the allylation of α-haloketones 1 with olefins under irradiation (λ = 530 nm) in the presence of [Cu(dap)2Cl] (dap = 2,9-di(p-anisyl)-1,10-phenanthroline) as the catalyst. They conducted control experiments to establish that

Photoredox catalysis in nickel-catalyzed C–H functionalization

• Lusina Mantry,
• Rajaram Maayuri,
• Vikash Kumar and
• Parthasarathy Gandeepan

Beilstein J. Org. Chem. 2021, 17, 2209–2259, doi:10.3762/bjoc.17.143

• transfer (HAT) and nickel catalysis [54]. The catalytic system consisting of iridium photocatalyst Ir[dF(CF3)ppy]2(dtbbpy)PF6, nickel catalyst NiBr2·3H2O, ligand 4,7-dimethoxy-1,10-phenanthroline (4,7-dOMe-phen), and 3-acetoxyquinuclidine was found to be optimal to afford the desired α-amino C–C coupled

Sustainable manganese catalysis for late-stage C–H functionalization of bioactive structural motifs

• Jongwoo Son

Beilstein J. Org. Chem. 2021, 17, 1733–1751, doi:10.3762/bjoc.17.122

• azidation was 7.5:1. Mn-catalyzed late-stage C–H azidation of bioactive molecules via electrophotocatalysis. a2.5 mol % of MnF2 was used. bNaN3 (5.0 equiv), MnF2 (10 mol %), 1,10-phenanthroline (20 mol %), TFA (4.0 equiv), and LiClO4 (2.0 equiv) were used with 4.5 mA for 15 h (5.0 mmol scale

A recent overview on the synthesis of 1,4,5-trisubstituted 1,2,3-triazoles

• Pezhman Shiri,
• Ali Mohammad Amani and
• Thomas Mayer-Gall

Beilstein J. Org. Chem. 2021, 17, 1600–1628, doi:10.3762/bjoc.17.114

•  24) [52]. A one-pot and multicomponent protocol for the synthesis of 5-selanyltriazoles 85 from the reaction of ethynylstibanes 82, organic azides 83, and diaryl diselenides 84 using catalytic amounts of CuI and 1,10-phenanthroline in DMSO at 60 °C under air with good to high yield was presented by

Recent advances in palladium-catalysed asymmetric 1,4–additions of arylboronic acids to conjugated enones and chromones

• Jan Bartáček,
• Jan Svoboda,
• Martin Kocúrik,
• Jaroslav Pochobradský,
• Alexander Čegan,
• Miloš Sedlák and
• Jiří Váňa

Beilstein J. Org. Chem. 2021, 17, 1048–1085, doi:10.3762/bjoc.17.84

• excellent in almost every example (Table 35) [14][15]. Selected addition products were used as intermediates in the total syntheses of various biologically active compounds (Scheme 24) [14][15][16]. Catalytic systems based on different groups of ligands The use of the chiral 1,10-phenanthroline ligand L15

Synthetic accesses to biguanide compounds

• Oleksandr Grytsai,
• Cyril Ronco and
• Rachid Benhida

Beilstein J. Org. Chem. 2021, 17, 1001–1040, doi:10.3762/bjoc.17.82

• -phenanthroline in refluxing DMF as an optimal catalytic system, the formation of the biguanide intermediate proceeded cleanly, followed by N-arylation to provide a series of N1-aryl heptasubstituted biguanides in gratifying 63–81% yield (Scheme 41). Interestingly, Štrukil et al. reported that the use of two

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

• Shivani Gulati,
• Stephy Elza John and
• Nagula Shankaraiah

Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71

• . One such demonstration was reported by Padmini and co-workers [64] wherein a four-component reaction between substituted aldehydes 5, phenanthroline (63), malononitrile (51) and isocyanides 21 afforded pyrrolo[1,10]-phenanthrolines 64 in ethanol as a solvent with excellent yields. The conventional

• phenanthroline. 6 Pyrimidines/fused pyrimidines 6.1 Pyrimidines Pyrimidines are six-membered aromatic heterocycles containing two nitrogen atoms at positions 1 and 3. These are an important class of compounds depicting a wide range of biological activities such as COX inhibitors, anti-inflammatory, anticancer

Using multiple self-sorting for switching functions in discrete multicomponent systems

• Amit Ghosh and
• Michael Schmittel

Beilstein J. Org. Chem. 2020, 16, 2831–2853, doi:10.3762/bjoc.16.233

• from [Cu(25)]+ and translocated to the free phenanthroline sites of the deck 27. The ensuing complex [Cu3(27)]3+ now commanded the nanoslider 26•29 to dismantle and to transfer the biped 29 thus enabling the formation of the alternative device [Cu3(27)(29)]3+. In essence, a single input (Zn2+) was

• the concurrent generation of [Cu2(28)(31)]2+, with the latter complex representing a three-component nanorotor operating at 46 kHz at room temperature (state SelfSORT-II). In [Cu2(28)(31)]2+ the rotator 28 exchanged rapidly between the two peripheral copper(I) phenanthroline sites of 31. Importantly

• between the states was accomplished by the addition of twice 2-ferrocenyl-1,10-phenanthroline (69) followed by the addition of copper(I) ions (Figure 19). In the state SelfSORT-I, representing an incomplete self-sorted mixture of ten components, piperidine (70) was firmly bound at the zinc porphyrin

Synthesis and investigation of quadruplex-DNA-binding, 9-O-substituted berberine derivatives

• Jonas Becher,
• Daria V. Berdnikova,
• Heiko Ihmels and
• Christopher Stremmel

Beilstein J. Org. Chem. 2020, 16, 2795–2806, doi:10.3762/bjoc.16.230

• a lower affinity [38]. Along the same line, the influence of the length and substituents of the side chains at the G4-DNA ligands have been assessed for quinolinium [43], indoloquinoline [44][45], phenanthroline [46], phenothiazine [47], and thiazole orange [48] derivatives. In these studies, the

Catalytic trifluoromethylation of iodoarenes by use of 2-trifluoromethylated benzimidazoline as trifluoromethylating reagent

• Tatsuhiro Uchikura,
• Nanami Kamiyama,
• Taisuke Ishikawa and
• Takahiko Akiyama

Beilstein J. Org. Chem. 2020, 16, 2442–2447, doi:10.3762/bjoc.16.198

• -withdrawing (–CF3, 4g) groups furnished 3a in low yields. Moreover, other electron-withdrawing ligands, i.e., phenanthroline derivatives (4h and 4i), and electron-donating ligands such as 2,2’-biimidazole (4j) and tetramethylethylenediamine (4k) gave inferior results. We next screened for the generality of

Oxime radicals: generation, properties and application in organic synthesis

• Igor B. Krylov,
• Stanislav A. Paveliev,
• Alexander S. Budnikov and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2020, 16, 1234–1276, doi:10.3762/bjoc.16.107

• that the presence of 1,10-phenanthroline is necessary to stabilize the intermediate CuCF3. Aromatic oximes with various electron-donating and electron-withdrawing substituents afford cyclization products in high yields (products 147a–d). In addition to aryl oximes, benzyl and tert-butyl substituted

• aliphatic amine ligands (N,N,N′,N′-tetramethylethylenediamine and 1,1,4,7,10,10-hexamethyltriethylenetetramine) showed moderate results and aromatic nitrogen-containing ligands (2,2’-bipyridine and phenanthroline) were even less efficient for the synthesis of target the isoxazolines. Both aromatic (products

Activated carbon as catalyst support: precursors, preparation, modification and characterization

• Melanie Iwanow,
• Tobias Gärtner,
• Volker Sieber and
• Burkhard König

Beilstein J. Org. Chem. 2020, 16, 1188–1202, doi:10.3762/bjoc.16.104

• et al. demonstrated the preparation of carbon materials with high surface areas from protic ionic liquids and salts. The precursors have low-molecular weights, are available and cheap. Preparation of the carbon materials is simple: Neutralization of the nitrogen-containing bases, e.g., phenanthroline

Synthesis and anticancer activity of bis(2-arylimidazo[1,2-a]pyridin-3-yl) selenides and diselenides: the copper-catalyzed tandem C–H selenation of 2-arylimidazo[1,2-a]pyridine with selenium

• Mio Matsumura,
• Tsutomu Takahashi,
• Hikari Yamauchi,
• Shunsuke Sakuma,
• Yukako Hayashi,
• Tadashi Hyodo,
• Tohru Obata,
• Kentaro Yamaguchi,
• Yasuyuki Fujiwara and
• Shuji Yasuike

Beilstein J. Org. Chem. 2020, 16, 1075–1083, doi:10.3762/bjoc.16.94

• anticancer activity are described. The double C–H selenation of imidazo[1,2-a]pyridine with Se powder was catalyzed by CuI (10 mol %) ligated with 1,10-phenanthroline (10 mol %) at 130 °C under aerobic conditions. The selenides or diselenides were prepared almost selectively using selenium powder in an

• -phenanthroline catalytic system [28]. Guo, Han, et al. reported a method that used a Cu(OAc)2/1,10-phenanthroline catalyst in the presence of KOH (2 equiv); this method replaced the aryl source from an arylboronic acid with an aryl iodide [30]. Zhou et al. reported the reactions of imidazopyridines, Se powder

• , and aryl halides in the presence of Na2CO3 (2 equiv) using a NiBr2/2,2-bipyridine system [31]. We also developed reactions of imidazopyridines, Se powder, and triarylbismuthanes using a CuI/1,10-phenanthroline catalytic system that did not require a base or an additive [32]. On the other hand, the