Deep-blue emitting 9,10-bis(perfluorobenzyl)anthracene

• Long K. San,
• Sebastian Balser,
• Brian J. Reeves,
• Tyler T. Clikeman,
• Yu-Sheng Chen,
• Steven H. Strauss and
• Olga V. Boltalina

Beilstein J. Org. Chem. 2025, 21, 515–525, doi:10.3762/bjoc.21.39

• ratio was found to be 1.74 (theoretical = 1.75), confirming the composition to be ANTH(BnF)2. Slow evaporation of a CH2Cl2 solution of 9,10-ANTH(BnF)2 at 2 °C afforded off-white plates suitable for X-ray diffraction. The structure shown in Figure 2 (top panel) confirmed the 9,10-substitution pattern

Extension of the π-system of monoaryl-substituted norbornadienes with acetylene bridges: influence on the photochemical conversion and storage of light energy

• Robin Schulte,
• Dustin Schade,
• Thomas Paululat,
• Till J. B. Zähringer,
• Christoph Kerzig and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 3061–3068, doi:10.3762/bjoc.20.254

• is no obvious correlation between the quantum yields of the photoreactions and substitution pattern of the norbornadiene in this series, except for a rough trend that naphthyl-linked derivatives, in particular the ones substituted in the 2-position, have lower quantum yields than the phenyl-linked

Copper-catalyzed yne-allylic substitutions: concept and recent developments

• Shuang Yang and
• Xinqiang Fang

Beilstein J. Org. Chem. 2024, 20, 2739–2775, doi:10.3762/bjoc.20.232

• developments and illustrates the influences of copper salt, ligand, and substitution pattern of the substrate on the regioselectivity and stereoselectivity. Keywords: copper-catalysis; copper vinyl allenylidene intermediate; 1,3-enyne; 1,4-enyne; yne-allylic substitution; Introduction Copper is earth

Synthesis of benzo[f]quinazoline-1,3(2H,4H)-diones

• Ruben Manuel Figueira de Abreu,
• Peter Ehlers and
• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 2708–2719, doi:10.3762/bjoc.20.228

• properties All synthesized compounds exhibit photoluminescence by excitation with UV light. Hence, we studied the photophysical properties of all obtained derivatives 5 by steady-state absorption and fluorescence spectroscopy. The influence of the substitution pattern on the photophysical properties is

• presence of only one donor group is advantageous. Interestingly, the quantum yields of 5a (12%), 5g (13%), 5h (8%), and 5i (3%) are comparatively lower than in case of 5g and 5f. It is reasonable to assume that this large difference is caused by the chosen substitution pattern and can be used for further

Computational design for enantioselective CO₂ capture: asymmetric frustrated Lewis pairs in epoxide transformations

• Maxime Ferrer,
• Iñigo Iribarren,
• Tim Renningholtz,
• Ibon Alkorta and
• Cristina Trujillo

Beilstein J. Org. Chem. 2024, 20, 2668–2681, doi:10.3762/bjoc.20.224

• into readily available substrates such as epoxides, resulting in the formation of polycarbonates or monomeric cyclic carbonates [22]. Depending on the substitution pattern in the epoxide, a chiral centre is present in the product. The insertion of CO2 into epoxides has been the subject of numerous

Transition-metal-free decarbonylation–oxidation of 3-arylbenzofuran-2(3H)-ones: access to 2-hydroxybenzophenones

• Bhaskar B. Dhotare,
• Seema V. Kanojia,
• Chahna K. Sakhiya,
• Amey Wadawale and
• Dibakar Goswami

Beilstein J. Org. Chem. 2024, 20, 2655–2667, doi:10.3762/bjoc.20.223

• substitution at the 4-position of benzofuranone hindered the reaction, leading to a very poor yield of the desired benzophenone product. Further, to confirm the structure and the substitution pattern in the 2-hydroxybenzophenones, single crystal XRD data were collected for the representative compounds 4ja, 4fb

Natural resorcylic lactones derived from alternariol

• Joachim Podlech

Beilstein J. Org. Chem. 2024, 20, 2171–2207, doi:10.3762/bjoc.20.187

Harnessing the versatility of hydrazones through electrosynthetic oxidative transformations

• Aurélie Claraz

Beilstein J. Org. Chem. 2024, 20, 1988–2004, doi:10.3762/bjoc.20.175

• -methoxymethylpyrrolidine)hydrazones could be also key intermediates for the asymmetric synthesis of α-substituted aldehydes and ketones [18][19]. Interestingly, depending on the substitution pattern, the C=N bond can feature different electronic properties [20]. For instance, various hydrazones have been employed for the

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

• ]. As expected, the use of the flow reaction system significantly increased yields, although the yields obtained in the reactions of substrates having an electron-donating methoxy group were low to moderate regardless of the substitution pattern (Table 2, entries 1, 2, and 6). Indeed, when a methoxy

A new platform for the synthesis of diketopyrrolopyrrole derivatives via nucleophilic aromatic substitution reactions

• Vitor A. S. Almodovar and
• Augusto C. Tomé

Beilstein J. Org. Chem. 2024, 20, 1933–1939, doi:10.3762/bjoc.20.169

• . Furthermore, the reaction with 4-(acetylamino)benzenethiol led to the selective formation of the disubstituted compound 3c in 53% yield. Phenols are less nucleophilic than thiols and, depending on the substitution pattern, a stronger base is often required to generate the corresponding alkoxide, which is the

Electrophotochemical metal-catalyzed synthesis of alkylnitriles from simple aliphatic carboxylic acids

• Yukang Wang,
• Yan Yao and
• Niankai Fu

Beilstein J. Org. Chem. 2024, 20, 1497–1503, doi:10.3762/bjoc.20.133

• conversion of simple aliphatic carboxylic acids into alkylnitriles. Notably, this new decarboxylative cyanation protocol exhibited extraordinary insensitivity to substitution pattern of alkyl acids, affording the corresponding alkylnitriles including primary and tertiary alkylnitriles with good reaction

• functional group compatibility and is applicable to alkyl acids with all substitution pattern. Due to the wide utility of alkylnitriles, we expect this method to be widely adopted within the synthetic and medicinal chemistry communities. The present work also demonstrated electrophotochemical transition

Photoswitchable glycoligands targeting Pseudomonas aeruginosa LecA

• Yu Fan,
• Ahmed El Rhaz,
• Stéphane Maisonneuve,
• Emilie Gillon,
• Maha Fatthalla,
• Franck Le Bideau,
• Guillaume Laurent,
• Samir Messaoudi,
• Anne Imberty and
• Juan Xie

Beilstein J. Org. Chem. 2024, 20, 1486–1496, doi:10.3762/bjoc.20.132

• the half-live varied from 26 h to 29 days at room temperature depending on the type of glycosidic linkage and the substitution pattern on the azobenzene moiety. The bistability of the azobenzene derivatives is suitable for the investigation of azobenzene isomers on the binding affinity with LecA. All

Synthesis of substituted triazole–pyrazole hybrids using triazenylpyrazole precursors

• Simone Gräßle,
• Laura Holzhauer,
• Nicolai Wippert,
• Olaf Fuhr,
• Martin Nieger,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2024, 20, 1396–1404, doi:10.3762/bjoc.20.121

• benzylic residues differed depending on the benzylic residue's functional groups and the pyrazole substitution pattern. For starting materials 15a and 15d, an excess of product 17 was usually observed. With the ester-functionalized triazene 15c and m-substituted benzylic reagents, regioisomer 18 was the

Phenotellurazine redox catalysts: elements of design for radical cross-dehydrogenative coupling reactions

• Alina Paffen,
• Christopher Cremer and
• Frederic W. Patureau

Beilstein J. Org. Chem. 2024, 20, 1292–1297, doi:10.3762/bjoc.20.112

• this reaction: PTeZ1 (3aa, 73% after 3 h). In other words, the cyclic phenotellurazine character of the catalyst does not seem to be essential in the context of this particular reaction, as opposed to the ortho/para substitution pattern of Te- and N-atoms. Nevertheless, all results considered, we

Domino reactions of chromones with activated carbonyl compounds

• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 1256–1269, doi:10.3762/bjoc.20.108

• was observed for the yields depending on the substitution pattern. Instead, the individual purity and quality of the dienes played an important role. Reflux of an EtOH solution of 23a in the presence of PTSA (para-toluenesulfonic acid) afforded benzophenone 24a in 50% yield. The reaction of 6a–r with

• building blocks is their dense functionalization in combination with their (commercial) availability. On the other hand, highly substituted or functionalized chromones have to be prepared in multi-step syntheses. In general, the substitution pattern of the chromone does not seem to have a great influence

Synthesis and optical properties of bis- and tris-alkynyl-2-trifluoromethylquinolines

• Stefan Jopp,
• Franziska Spruner von Mertz,
• Peter Ehlers,
• Alexander Villinger and
• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 1246–1255, doi:10.3762/bjoc.20.107

• steady state absorption and fluorescence spectroscopy which give insights of the influence of the substitution pattern and of the type of substituents on the optical properties. Keywords: alkynes; catalysis; fluorescence; heterocycles; palladium; Introduction Quinoline is a well-known core structure

• properties of selected products, bis- and tris-alkynylated quinolines, were studied to gain insights into how the substitution pattern at different positions may alter the optical properties. Results and Discussion The starting material, 4,8-dibromo-2-(trifluoromethyl)quinoline (4), was synthesized from 2

• first insights on how the optical properties can be fine-tuned by the substitution pattern of the arylalkyne. The key optical properties are summarized in Table 2. All molecules display relatively high quantum yields (QYs) with the highest being 0.66 for 6a and the lowest 0.54 for 12a. This is in

Synthesis and properties of 6-alkynyl-5-aryluracils

• Ruben Manuel Figueira de Abreu,
• Till Brockmann,
• Alexander Villinger,
• Peter Ehlers and
• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 898–911, doi:10.3762/bjoc.20.80

• synthesized by other methods and the single Suzuki reaction on uracil is well studied [42][69][70][71]. Physical properties The photophysical properties of selected derivatives were investigated by steady-state absorption and photoluminescence spectroscopy. The influence of the substitution pattern on the

• compounds show a very similar absorption band, indicating that the first transition state (S0 → S1) does not seem to be affected by the substitution pattern. Furthermore, all compounds show broadened absorption bands and no major differences in the first absorption band were observed. The greatest

• could be observed with an absorption band at 273 nm and a shoulder at 306 nm. The second highest peak was observed for 5f, followed by 5m. Only one broadened peak was observed in both cases. The influence of the substitution pattern could be revealed by comparing the two regioisomers 5d and 5k. As a

(Bio)isosteres of ortho- and meta-substituted benzenes

• H. Erik Diepers and
• Johannes C. L. Walker

Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78

• ortho-benzenes have, with different substitution patterns, also been suggested as potential bioisosteric replacements of meta-benzenes. In some cases, similar synthetic approaches may be adopted, but in many a new route is required to access the new substitution pattern. 1,3-Disubstituted bicyclo[2.1.1

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

• be achieved by changing the substitution pattern of the terpyridine from 6,6” to 4,4” (Figure 12). Due to the repulsion between the nitrogen lone pairs, the 4,4”-substituted terpy adopts a “U” conformation in the non-complexed state and can be switched by metal coordinating to a “W” open conformation

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

• , acetonitrile, and the triflate counterion [66]. Theoretical calculation of binding constants predict that esters coordinate more strongly than alkynes, and water [68]. Alkenes have been shown in some cases to coordinate more strongly than alkynes, but the trend depends on substitution pattern (alkynes can

Photochromic derivatives of indigo: historical overview of development, challenges and applications

• Gökhan Kaplan,
• Zeynel Seferoğlu and
• Daria V. Berdnikova

Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23

• the photoreaction, is advantageous for applications in bulk materials because the photoisomers have decreased absorbance at the excitation wavelength [9]. Depending on the substitution pattern, the quantum yields for the E–Z photoisomerization of indigo photochromes vary from 0.001 to 0.46 and the

Photoinduced in situ generation of DNA-targeting ligands: DNA-binding and DNA-photodamaging properties of benzo[c]quinolizinium ions

• Julika Schlosser,
• Olga Fedorova,
• Yuri Fedorov and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 101–117, doi:10.3762/bjoc.20.11

• , both as photo-controllable DNA binder and as DNA-damaging photosensitizer. Still, some key parameters have to be optimized by variation of the substitution pattern. For example, the water solubility of the styrylpyridine substrates has to be increased, and the excitation wavelength for the

Synthesis of 7-azabicyclo[4.3.1]decane ring systems from tricarbonyl(tropone)iron via intramolecular Heck reactions

• Aaron H. Shoemaker,
• Elizabeth A. Foker,
• Elena P. Uttaro,
• Sarah K. Beitel and
• Daniel R. Griffith

Beilstein J. Org. Chem. 2023, 19, 1615–1619, doi:10.3762/bjoc.19.118

• the same substitution pattern as substrate 7 tend to give poor yields in similar intramolecular Heck reactions [20]. Moreover, it was found that substrates on which the halide is cis to an additional methyl substituent (used to forge the ethylidene-substituted polycycle common to many alkaloids) often

Consecutive four-component synthesis of trisubstituted 3-iodoindoles by an alkynylation–cyclization–iodination–alkylation sequence

• Nadia Ledermann,
• Alae-Eddine Moubsit and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2023, 19, 1379–1385, doi:10.3762/bjoc.19.99

• that are accessible in two steps from indole carboxylates [36]. Our two-step approach taking advantage of a de novo formation of 3-iodoindoles with variable substitution pattern in a consecutive four-component process provides a concise access to the aforementioned class of emitters. For example the

Palladium-catalyzed enantioselective three-component synthesis of α-arylglycine derivatives from glyoxylic acid, sulfonamides and aryltrifluoroborates

• Bastian Jakob,
• Nico Schneider,
• Luca Gengenbach and
• Georg Manolikakes

Beilstein J. Org. Chem. 2023, 19, 719–726, doi:10.3762/bjoc.19.52

• . However, depending on the nature/substitution pattern of the arylboronic acid, some of the arylglycine products could only be obtained in very low enantioselectivities. This can be attributed to a fast, uncatalyzed racemic background reaction of the boronic acids, in particular for electron-rich or