Introducing a new 7-ring fused diindenone-dithieno[3,2-b:2',3'-d]thiophene unit as a promising component for organic semiconductor materials

• Valentin H. K. Fell,
• Joseph Cameron,
• Alexander L. Kanibolotsky,
• Eman J. Hussien and
• Peter J. Skabara

Beilstein J. Org. Chem. 2022, 18, 944–955, doi:10.3762/bjoc.18.94

• possible to convert 25 into the corresponding pinacol ester, 2,6-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)dithieno[3,2-b:2’,3’-d]thiophene (26) by stirring 25 with pinacol in refluxing toluene, but this has no beneficial impact on the subsequent cross-coupling. Compound 26 has been published

• aqueous lithium hydroxide, THF, 4 h, 94% [15]; e) copper powder, quinoline, 230 °C, 1 h, 81% [15]; f) N-bromosuccinimide, CHCl3/glacial acetic acid, 0 °C, 1 h, rt, 1.5 h, 94% [15] ; g) n-BuLi, −90 °C, 20 min, triisopropyl borate, −80 °C, anhydrous THF, rt, overnight, 97% [34]; h) pinacol, toluene, 115 °C

On Reuben G. Jones synthesis of 2-hydroxypyrazines

• Pierre Legrand and
• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 935–943, doi:10.3762/bjoc.18.93

• ), 2.50 (s, 3H); 13C NMR (CD3COOD) δ 158.5, 155.1, 137.5, 130.4, 130.3, 129.3, 126.4, 121.2, 18.0. Note: in some cases, the chromatography fraction containing compound 4{1,1} had to be recrystallized from toluene. General protocol for the experiments described in Table 2, description of entry 20. In a

• water, and dried under vacuum at 60 °C. A chromatography over silica gel of this solid (cyclohexane/ethyl acetate 2:1) at 60 °C gave first a fraction containing compound 4{1,2} which was further purified by dispersion in a boiling mixture of toluene and cyclohexane (0.09 g, 3.5%) and then compound 3{1,2

Post-synthesis from Lewis acid–base interaction: an alternative way to generate light and harvest triplet excitons

• Hengjia Liu and
• Guohua Xie

Beilstein J. Org. Chem. 2022, 18, 825–836, doi:10.3762/bjoc.18.83

• Lewis basic fluorescent compounds 3–14. (a) PL spectra of compound 6 in toluene after addition of 0.0 (black line), 0.1 (red line), 0.3 (green line), 0.7 (blue line), 1.3 mol equiv (orange line) B(C6F5)3. (b) EL spectra of the device with compound 6 at a constant current density of 111 mA cm−2 for 0.00

• , Weinheim. This content is not subject to CC BY 4.0. Figure 6c and 6d were reproduced from [32] with permission from The Royal Society of Chemistry. This content is not subject to CC BY 4.0. Photos of a solution of compound 12 and B(C6F5)3 at different ratios in toluene under a 365 nm UV lamp. Figure 7 was

Thiophene/selenophene-based S-shaped double helicenes: regioselective synthesis and structures

• Mengjie Wang,
• Lanping Dang,
• Wan Xu,
• Zhiying Ma,
• Liuliu Shao,
• Guangxia Wang,
• Chunli Li and
• Hua Wang

Beilstein J. Org. Chem. 2022, 18, 809–817, doi:10.3762/bjoc.18.81

• toluene through irradiation by a 450 W Hg medium-pressure lamp for 1.5 h, only one type of ring-closing product with two benzene rings formed in the same direction, i.e., S-shaped double helicenes DH-1–3 were obtained in yields of 62%, 30%, and 53%, respectively (Figure 2). The double oxidative

• toluene (6 mL), iodine (7.3 mg, 0.028 mmol, 2.0 equiv) and excess propylene oxide were added. The reaction solution was irradiated with a 450 W unfiltered Hg medium-pressure lamp for 1.5 h. The reaction was quenched with saturated Na2SO3 solution (5 mL). The reaction mixture was extracted with CH2Cl2 (3

Copper-catalyzed multicomponent reactions for the efficient synthesis of diverse spirotetrahydrocarbazoles

• Shao-Cong Zhan,
• Ren-Jie Fang,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2022, 18, 796–808, doi:10.3762/bjoc.18.80

• dienophiles in refluxing toluene afforded diverse spirotetrahydrocarbazoles. This reaction is an important development of the Levy reaction by using 2-methylindole to replace ethyl indole-2-acetate and successfully provides facile access to important polysubstituted spiro[carbazole-3,3'-indolines], spiro

• served as model substrates for the optimization of reaction conditions. Inspired by our previous work [75][76][77], we first screened different catalysts (Table 1, entries 1−5) with toluene as the solvent and found that CuSO4 was the best choice, providing 1a in 58% isolated yield. Notably, the yield of

• ), benzaldehyde (0.6 equiv), and 3-methyleneoxindole (1.0 equiv) with CuSO4 (0.1 mmol) as the catalyst in toluene (10.0 mL) reacting at 110 °C for 3 h were selected as the optimal reaction conditions. Having established the optimal reaction conditions, we first sought to determine the generality of the aromatic

Synthesis of odorants in flow and their applications in perfumery

• Merlin Kleoff,
• Paul Kiler and
• Philipp Heretsch

Beilstein J. Org. Chem. 2022, 18, 754–768, doi:10.3762/bjoc.18.76

• solution of (R)-carvone (25) in toluene is merged with a stream of hydrogen and the resulting segmented flow is passed through a column reactor containing a dimethylpolysilane-modified platinum catalyst (DMPS-Pt, 26), immobilized on carbon/calcium phosphate. At a temperature of 25 °C using 1.4 equivalents

Tri(n-butyl)phosphine-promoted domino reaction for the efficient construction of spiro[cyclohexane-1,3'-indolines] and spiro[indoline-3,2'-furan-3',3''-indolines]

• Hui Zheng,
• Ying Han,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2022, 18, 669–679, doi:10.3762/bjoc.18.68

• and 2 in Table 1). Additionally, no reaction was observed when triphenylphosphine was used as catalyst (Table 1, entry 3). However, in the presence of tri(n-butyl)phosphine, the reaction in methylene dichloride, chloroform, and toluene at room temperature gave the expected functionalized spiro

• triphenylphosphine. It should be pointed out that the synthesis of polysubstituted cyclohexanones was reported by a tri(n-butyl)phosphine-catalyzed reaction of 1,4-dien-3-ones with 2-aryl-1,1-dicyanoalkenes [36]. At higher temperature (50 °C), the yield of the product 3a increased to 40% (in CH2Cl2), 65% (in toluene

A study of the photochemical behavior of terarylenes containing allomaltol and pyrazole fragments

• Constantine V. Milyutin,
• Andrey N. Komogortsev,
• Boris V. Lichitsky and
• Valeriya G. Melekhina

Beilstein J. Org. Chem. 2022, 18, 588–596, doi:10.3762/bjoc.18.61

• in a solution of DMSO-d6. UV irradiation at a wavelength of 365 nm for 48 h in an NMR tube did not lead to any transformations of the starting pyrazole 16. Our attempts to carry out the photocyclization of pyrazole 16 in various solvents (DMF, acetonitrile, toluene, ethanol, methylene chloride

Synthesis of sulfur karrikin bioisosteres as potential neuroprotectives

• Martin Pošta,
• Václav Zima,
• Lenka Poštová Slavětínská,
• Marika Matoušová and
• Petr Beier

Beilstein J. Org. Chem. 2022, 18, 549–554, doi:10.3762/bjoc.18.57

• positions of oxygen to sulfur exchange. i) P4S10, THF; ii) 2-chloropropionyl chloride, Et3N; iii) Ph3P, NaOAc, Ac2O. i) Lawesson’s reagent, HMDO, toluene, MW irradiation, 120 °C, 60 min. i) P4S10 or Lawesson’s reagent, see table for conditions; ii) 2-chloropropionyl chloride, Et3N, DCM, 0 °C; iii) AcONa

• , Ph3P, Ac2O, reflux. aReported yields are 1H NMR yields. bIsolated yield. i) LiHMDS, MeI, THF, −78 °C. i) a) NaOH, MeOH/H2O, rt, Amberlyst 15 [H+], b) AcOH 70% aq, reflux, 2 h; ii) a) EtOCOCl, pyridine, b) Et3N, CH2Cl2; iii) (Ph3P)4Pd, BSA, THF. i) Lawesson’s reagent, HMDO, toluene, MW irradiation (120

Chemistry of polyhalogenated nitrobutadienes, 17: Efficient synthesis of persubstituted chloroquinolinyl-1H-pyrazoles and evaluation of their antimalarial, anti-SARS-CoV-2, antibacterial, and cytotoxic activities

• Viktor A. Zapol’skii,
• Isabell Berneburg,
• Ursula Bilitewski,
• Melissa Dillenberger,
• Katja Becker,
• Stefan Jungwirth,
• Aditya Shekhar,
• Bastian Krueger and
• Dieter E. Kaufmann

Beilstein J. Org. Chem. 2022, 18, 524–532, doi:10.3762/bjoc.18.54

• compared to chlorine [28]. The reaction of oxazolidine 6 with 2.3 equivalents of 7-chloro-4-hydrazinylquinoline in toluene at 90–95 °C for 30 h led to the formation of pyrazole 7 (yield 23%) together with considerable amounts of a resin (Scheme 5). We suggest that the lower yield of alcohol 7 is due to the

Substituent effect on TADF properties of 2-modified 4,6-bis(3,6-di-tert-butyl-9-carbazolyl)-5-methylpyrimidines

• Irina Fiodorova,
• Tomas Serevičius,
• Rokas Skaisgiris,
• Saulius Juršėnas and
• Sigitas Tumkevicius

Beilstein J. Org. Chem. 2022, 18, 497–507, doi:10.3762/bjoc.18.52

• to 200 meV), beneficial for efficient thermal triplet upconversion. Absorption and emission properties Absorption (10−5 M toluene solutions) and emission spectra (1 wt % PMMA films) of the carbazole–pyrimidine TADF compounds are shown in Figure 3 and details are enclosed in Table 2. The absorption

• toluene solutions as well as 1 wt % PMMA (poly(methyl methacrylate)) films. The solid-state samples were prepared by dissolving the compounds and polymer or host material at appropriate ratios in toluene solution and then wet-casting the solutions on quartz substrates. The absorption spectra were recorded

• package Gaussian 09 [52]. The solvation behaviour of the surrounding toluene was estimated by the polarizable continuum model. Although the B3LYP/6-31G(d) theory level due to the neglected long-range exchange interaction can give less accurate results for calculated molecular geometries and transition

Bioinspired tetraamino-bisthiourea chiral macrocycles in catalyzing decarboxylative Mannich reactions

• Hao Guo,
• Yu-Fei Ao,
• De-Xian Wang and
• Qi-Qiang Wang

Beilstein J. Org. Chem. 2022, 18, 486–496, doi:10.3762/bjoc.18.51

• % yield) and only a slightly diminished selectivity (58% ee). Reactions in other more polar solvents including toluene, ethyl acetate, halohydrocarbons, and acetonitrile gave overall very good conversions, but with very low selectivity except for the reaction in ethyl acetate which afforded the product in

Tosylhydrazine-promoted self-conjugate reduction–Michael/aldol reaction of 3-phenacylideneoxindoles towards dispirocyclopentanebisoxindole derivatives

• Sayan Pramanik and
• Chhanda Mukhopadhyay

Beilstein J. Org. Chem. 2022, 18, 469–478, doi:10.3762/bjoc.18.49

• less polar solvent like toluene or DCM the desired product was not obtained. After investigatiing different solvents, it was revealed that CH3CN is the perfect solvent of choice (Table 1). Together, this screening resulted in the optimal conditions, which are: 1a (1 mmol), 2 (0.5 mmol) and Et3N (0.5

Comparative study of thermally activated delayed fluorescent properties of donor–acceptor and donor–acceptor–donor architectures based on phenoxazine and dibenzo[a,j]phenazine

• Saika Izumi,
• Prasannamani Govindharaj,
• Anna Drewniak,
• Paola Zimmermann Crocomo,
• Satoshi Minakata,
• Leonardo Evaristo de Sousa,
• Piotr de Silva,
• Przemyslaw Data and
• Youhei Takeda

Beilstein J. Org. Chem. 2022, 18, 459–468, doi:10.3762/bjoc.18.48

• (λPL = 502 nm) to toluene (λPL = 608 nm), and no PL was observed in a more polar solvent such as THF and CHCl3 (Figure 2). In addition, the shape of the PL spectrum changed from a vibrationally resolved shape typical of the emission from a locally excited state (1LE) to a Gaussian-type broad one

• typical to the emission from a charge–transfer excited state (CT). The CT emission was totally quenched in a solvent that is more polar than toluene (Figure 2). These photophysical observations are consistent with those of the D–A–D-type compound POZ-DBPHZ [17], indicating that one D–A pair is sufficient

• collected in Table S1 (Supporting Information File 1). The Tamm–Dancoff (TDA) approximation was used in all excited state calculations and solvent effects were included by means of the polarizable continuum model (PCM) associated with a perturbative state specific solvation method using toluene as solvent

Menadione: a platform and a target to valuable compounds synthesis

• Acácio S. de Souza,
• Ruan Carlos B. Ribeiro,
• Dora C. S. Costa,
• Fernanda P. Pauli,
• David R. Pinho,
• Matheus G. de Moraes,
• Fernando de C. da Silva,
• Luana da S. M. Forezi and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

• )ruthenium(II) dichloride as catalyst. Then, a BF3·OEt2-catalzyed migration of the methyl group to the C-2 position and removal of the tert-butoxy group in a 1,1,1,3,3,3-hexafluoroisopropanol (HFIP)/toluene mixture afforded 2-methyl-1,4-benzoquinone (29). Finally, a Diels–Alder reaction was performed with

Site-selective reactions mediated by molecular containers

• Rui Wang and
• Yang Yu

Beilstein J. Org. Chem. 2022, 18, 309–324, doi:10.3762/bjoc.18.35

• mixture of different products will form through various pathways [50][51][52][53]. By applying the cage host A, the authors realized a highly site-selective radical addition reaction of o-quinone 10 and substituted toluene 11, giving rise to the unusual 1,4-adduct 15 (Figure 3) [54]. Specifically, upon

Unexpected chiral vicinal tetrasubstituted diamines via borylcopper-mediated homocoupling of isatin imines

• Marco Manenti,
• Leonardo Lo Presti,
• Giorgio Molteni and
• Alessandra Silvani

Beilstein J. Org. Chem. 2022, 18, 303–308, doi:10.3762/bjoc.18.34

• . Results and Discussion We began our investigation using the known (R)-1-methylisatin-derived N-tert-butanesulfinyl ketimine 1a, bis(pinacolato)diboron, CuSO4/(Cy)3P catalyst and benzylamine, as reported in Scheme 1. The first reaction was carried out at room temperature in toluene/water (5:1), as

• of water to the minimum necessary to solubilize the copper sulfate. Thus, performing the reaction in toluene/water 100:1, ketimine hydrolysis was almost entirely prevented and the yield of compound 2a raised to 52% (Table 1, entry 6). With regard to the ligand (Table 1, entries 7 and 8), PPh3 behaved

Regioselectivity of the S_EAr-based cyclizations and S_EAr-terminated annulations of 3,5-unsubstituted, 4-substituted indoles

• Jonali Das and
• Sajal Kumar Das

Beilstein J. Org. Chem. 2022, 18, 293–302, doi:10.3762/bjoc.18.33

• -workers in 2019 (Scheme 6) [16]. The authors observed that 17 could be cyclized under PhSO3H catalysis in toluene at 130 °C to tetrahydrobenzo[cd]indoles 18 in 57–90% yields as major products, together with minor amounts of the corresponding tetrahydrocyclopenta[e]indoles 19 (18:19 = 60:40 to >95:5). In

New efficient synthesis of polysubstituted 3,4-dihydroquinazolines and 4H-3,1-benzothiazines through a Passerini/Staudinger/aza-Wittig/addition/nucleophilic substitution sequence

• Long Zhao,
• Mao-Lin Yang,
• Min Liu and
• Ming-Wu Ding

Beilstein J. Org. Chem. 2022, 18, 286–292, doi:10.3762/bjoc.18.32

• 3,4-dihydroquinazoline 8a was then optimized (Table 1). As K2CO3 in different solvents (DMF, CH2Cl2 and toluene) were used, 0–72% yields of the product 8a were obtained (Table 1, entries 2–4). Utilizing a stronger base (NaOH and EtONa) resulted in a dark solution and no product was received (entries 5

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

• 30 mol % of dmeda as ligand in toluene at 135 °C for 72 h (Scheme 7). On the other hand, acetylenes with alkyl substitution showed lower reactivity. In addition, to increase the importance of iron catalysts as a versatile tool in organic synthesis, a novel iron-catalyzed domino Sonogashira coupling

• of Fe(acac)3 and a ligand (Scheme 10) [27]. The optimized reaction of phenylacetylene with 1-iodobenzene comprised 10 mol % of Fe(acac)3, 20 mol % of 2,2’-bipyridyl and 2 equiv of Cs2CO3 in toluene at 135 °C for 42 h. By using Fe(acac)3 as catalyst and 2,2’-bipyridine (25) as the ligand the best

Organocatalytic asymmetric nitroso aldol reaction of α-substituted malonamates

• Ekta Gupta,
• Narendra Kumar Vaishanv,
• Sandeep Kumar,
• Raja Krishnan Purshottam,
• Ruchir Kant and
• Kishor Mohanan

Beilstein J. Org. Chem. 2022, 18, 217–224, doi:10.3762/bjoc.18.25

• (2a) in toluene at 25 °C. Pleasingly, the hydroxyamination reaction proceeded smoothly to give the nitroso aldol product 4a in 80% yield and 60% ee (Table 1, entry 1). The influence of temperature was evaluated subsequently, and the reaction conducted at 0 °C without altering other parameters gave a

• attempts to enhance the enantioselectivity centered on the variation of solvents. The reaction was screened using various polar and nonpolar solvents, and toluene was found suitable in terms of the reaction rate, yield, and enantioselectivity (Table 1, entries 9–13). Other solvents such as EtOAc, DCM

• -methylmalonamate 1a (57 mg, 0.20 mmol, 1 equiv), nitrosobenzene 2a (26 mg, 0.24 mmol, 1.2 equiv) and (R,R)-TUC 3a (17 mg, 0.04 mmol, 0.2 equiv). Then, the round-bottomed flask was sealed, evacuated, and backfilled with nitrogen. The mixture was dissolved in 3 mL of anhydrous toluene and was kept stirring at 0 °C

Anomeric 1,2,3-triazole-linked sialic acid derivatives show selective inhibition towards a bacterial neuraminidase over a trypanosome trans-sialidase

• Peterson de Andrade,
• Sanaz Ahmadipour and
• Robert A. Field

Beilstein J. Org. Chem. 2022, 18, 208–216, doi:10.3762/bjoc.18.24

• steps from N-acetylneuraminic acid [26] – and terminal alkyne (72 µmol) in DMF/H2O 4:1 (1 mL) in a glass vial. The mixture was stirred for 24 h at 60 °C [33] and solvents were evaporated under vacuum with addition of toluene (3 × 5 mL). EtOAc (10 mL) was added to the crude and washed with H2O (3 × 5 mL

High-speed C–H chlorination of ethylene carbonate using a new photoflow setup

• Takayoshi Kasakado,
• Takahide Fukuyama,
• Tomohiro Nakagawa,
• Shinji Taguchi and
• Ilhyong Ryu

Beilstein J. Org. Chem. 2022, 18, 152–158, doi:10.3762/bjoc.18.16

• quite low (0.12 mL/min of toluene), the residence time was less than 14 seconds. More recent studies on flow C–H chlorination reactions focused on the use of Cl2 gas in situ generated by photolysis of sulfuryl chloride [10] or by acid treatment of NaOCl [11][12]. We thought that if rationally designed

• after the first report on the microflow chlorination of a toluene derivative by Jähnisch and co-workers, we propose a new photoflow setup for C–H chlorination using chlorine gas, applicable to scalable flow C–H chlorination. In our test reaction using C–H chlorination of ethylene carbonate (1

Chemical and chemoenzymatic routes to bridged homoarabinofuranosylpyrimidines: Bicyclic AZT analogues

• Sandeep Kumar,
• Jyotirmoy Maity,
• Banty Kumar,
• Sumit Kumar and
• Ashok K. Prasad

Beilstein J. Org. Chem. 2022, 18, 95–101, doi:10.3762/bjoc.18.10

• ) immobilized on polyacrylate (Lewatit), commonly known as Novozyme® 435 and Thermomyces lanuginosus lipase immobilized on silica, commonly known as Lipozyme® TL IM in different organic solvents, such as THF, acetonitrile, toluene, acetone, DIPE and 2-Me-THF. Vinyl acetate was used as acetyl donor at

Efficient synthesis of ethyl 2-(oxazolin-2-yl)alkanoates via ethoxycarbonylketene-induced electrophilic ring expansion of aziridines

• Yelong Lei and
• Jiaxi Xu

Beilstein J. Org. Chem. 2022, 18, 70–76, doi:10.3762/bjoc.18.6

• improve the yield (Table 1, entries 7–9). Solvent screening indicated that the same yield of 71% was obtained in toluene (Table 1, entry 13). However, lower yields were obtained in MeCN, THF, and 1,4-dioxane (Table 1, entries 10–12). Further optimizations in toluene were carried out. However, the yield

• solubility to all substrates than toluene, the optimal reaction conditions were selected as: diazo ester 1a (0.36 mmol) and 2a (0.3 mmol) in DCE (1 mL) were heated at 130 °C for 20 min with microwave heating. With the optimal reaction conditions in hand, we evaluated the scopes and generalities of both diazo

• , MeCN, and 1,4-dioxane were refluxed over CaH2; toluene was refluxed over Na with benzophenone as an indicator, and all solvents were freshly distilled prior to use. Flash column chromatography was performed using silica gel (normal phase, 200–300 mesh) from Branch of Qingdao Haiyang Chemical. Petroleum