Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

Non-noble metal-catalyzed cross-dehydrogenation coupling (CDC) involving ether α-C(sp³)–H to construct C–C bonds

• Hui Yu and
• Feng Xu

Beilstein J. Org. Chem. 2023, 19, 1259–1288, doi:10.3762/bjoc.19.94

• , tetrahydrofuran or tetrahydropyran can smoothly react with many methyl aryl ketones to obtain the desired coupling products (Scheme 6a) [54]. The mechanism of the dehydrogenation cross-coupling reaction may undergo a radical pathway. Initially, the tert-butoxy radical produced by the dissociation of t-BuOOH may

• , and TBHP acting as both an oxidant and a radical initiator. In 2015, Wang et al. reported the synthesis of quinoline lactones by the double oxidative dehydrogenation (DOD) reaction between glycine derivatives and tetrahydrofuran using the FeCl2/HCl/TBHP system (Scheme 19) [80]. This practical coupling

• pathway. Initially, a tert-butoxyl radical is generated by thermal decomposition. Then, the tert-butoxyl radical extracts an α-hydrogen atom from tetrahydrofuran to form tetrahydrofuran radical A. Sc(OTf)3 as a Lewis acid activates pyridine forming the pyridine complex B. Then, radical A adds to the more

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

Copper-catalyzed N-arylation of amines with aryliodonium ylides in water

• Kasturi U. Nabar,
• Bhalchandra M. Bhanage and
• Sudam G. Dawande

Beilstein J. Org. Chem. 2023, 19, 1008–1014, doi:10.3762/bjoc.19.76

• iodonium ylide 2a in the presence of 10 mol % of CuSO4·5H2O as a catalyst in solvents such as tetrahydrofuran, 1,4-dioxane, methanol, water, acetonitrile, N,N-dimethylformamide and toluene at 60 °C (Table 1, entries 9–14). The detailed investigation reveals that the arylation of aniline (1a) with iodonium

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

• conditions for the use of potassium aryltrifluoroborate salts (Table 1). A quick survey of different solvents showed that the reaction proceeds efficiently only in nitromethane (Table 1, entry 1). Reactions in other common solvents, such as ethyl acetate, acetonitrile, tetrahydrofuran or dichloromethane led

Transition-metal-catalyzed domino reactions of strained bicyclic alkenes

• Austin Pounder,
• Eric Neufeld,
• Peter Myler and
• William Tam

Beilstein J. Org. Chem. 2023, 19, 487–540, doi:10.3762/bjoc.19.38

Continuous flow synthesis of 6-monoamino-6-monodeoxy-β-cyclodextrin

• János Máté Orosz,
• Dóra Ujj,
• Petr Kasal,
• Gábor Benkovics and
• Erika Bálint

Beilstein J. Org. Chem. 2023, 19, 294–302, doi:10.3762/bjoc.19.25

• solvents. Alcohols were excluded as possible solvents, as they precipitate β-CD (1) and may cause side reactions, but aprotic solvents such as tetrahydrofuran (THF) or acetonitrile (MeCN) were found to be suitable for homogenous conditions, especially a H2O/THF 2:1 mixture. This solvent mixture was

Strategies to access the [5-8] bicyclic core encountered in the sesquiterpene, diterpene and sesterterpene series

• Cécile Alleman,
• Charlène Gadais,
• Laurent Legentil and
• François-Hugues Porée

Beilstein J. Org. Chem. 2023, 19, 245–281, doi:10.3762/bjoc.19.23

• precursor towards the tetrahydrofuran-ring formation. The intramolecular atom-transfer radical cyclization was thus carried out with achiral di-tert-butylbipyridine-ligated CuI 171 to generate the [5-8-5] scaffold 172 in 55% yield, while securing the C10 stereocenter in the required configuration and

An accelerated Rauhut–Currier dimerization enabled the synthesis of (±)-incarvilleatone and anticancer studies

• Tharun K. Kotammagari,
• Sweta Misra,
• Sayantan Paul,
• Sunita Kunte,
• Rajesh G. Gonnade,
• Manas K. Santra and
• Asish K. Bhattacharya

Beilstein J. Org. Chem. 2023, 19, 204–211, doi:10.3762/bjoc.19.19

• intermediate A tetrahydrofuran intermediate B with cis-fused ring systems is formed as seen in the existing literature [7]. A proton transfer of enolate moiety B yields another enolate C followed by the β-alkoxy elimination [17] of intermediate C to form intermediate D. The intermediate D on protonation leads

1,4-Dithianes: attractive C2-building blocks for the synthesis of complex molecular architectures

• Bram Ryckaert,
• Ellen Demeyere,
• Frederick Degroote,
• Hilde Janssens and
• Johan M. Winne

Beilstein J. Org. Chem. 2023, 19, 115–132, doi:10.3762/bjoc.19.12

• blocks with respect to their homologous counterparts. This is mainly due to their problematic metalation reactions (Scheme 2). Many ‘olane-type’ saturated heterocycles do not afford stable metalated species [12][13][14][15]. The most well-known example of this is tetrahydrofuran, which decomposes in a

Synthetic study toward tridachiapyrone B

• Morgan Cormier,
• Florian Hernvann and
• Michaël De Paolis

Beilstein J. Org. Chem. 2022, 18, 1741–1748, doi:10.3762/bjoc.18.183

• chiral tetrahydrofuran (Scheme 1b). To assemble the skeleton of the natural product, we developed a new strategy in which the α,α’-dimethoxy-γ-pyrone motif 2 was first desymmetrized by a sequence encompassing the conjugate addition of 2-lithio-1,3-dithiane, elimination of methoxide lithium, and

Formal total synthesis of macarpine via a Au(I)-catalyzed 6-endo-dig cycloisomerization strategy

• Jiayue Fu,
• Bingbing Li,
• Zefang Zhou,
• Maosheng Cheng,
• Lu Yang and
• Yongxiang Liu

Beilstein J. Org. Chem. 2022, 18, 1589–1595, doi:10.3762/bjoc.18.169

• ) in tetrahydrofuran (THF), resulting in the formation of naphthol 12 [12][13], a key intermediate in the previous total synthesis of macarpine (1) reported by Ishikawa (Scheme 6). To simplify the synthetic procedure, a more straightforward strategy was proposed by using alkynyl ketone 9 [27][28][29

Preparation of an advanced intermediate for the synthesis of leustroducsins and phoslactomycins by heterocycloaddition

• Anaïs Rousseau,
• Guillaume Vincent and
• Cyrille Kouklovsky

Beilstein J. Org. Chem. 2022, 18, 1385–1395, doi:10.3762/bjoc.18.143

• completion of the total synthesis via the preparation and coupling of the fragment 5 is under study in our laboratory. Experimental Unless otherwise stated, all reactions were conducted in oven-dried glassware under an atmosphere of dry argon. Tetrahydrofuran was distilled over sodium/benzophenone ketyl

Thermally activated delayed fluorescence (TADF) emitters: sensing and boosting spin-flipping by aggregation

• Ashish Kumar Mazumdar,
• Gyana Prakash Nanda,
• Nisha Yadav,
• Upasana Deori,
• Upasha Acharyya,
• Bahadur Sk and
• Pachaiyappan Rajamalli

Beilstein J. Org. Chem. 2022, 18, 1177–1187, doi:10.3762/bjoc.18.122

• . (TL: toluene, DIO: 1,4-dioxane, THF: tetrahydrofuran, DCM: dichloromethane). Transient photoluminescence decay (λex = 375 nm) of (a) BPy-pTC and (b) BPy-p3C in degassed THF (10 µM) at room temperature. AIEE studies: Emission spectra (λex = 375 nm, 10 µM) of (a) BPy-pTC and (d) BPy-p3C in THF with

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

• donor–acceptor interaction [21]. With this strategy, fusing those systems should lead to greater π-delocalisation [15][22]. Moreover, the fused core system is flanked by thiophene groups with ethylhexyl groups which impart solubility [5] in common organic solvents such as tetrahydrofuran, chloroform or

• iodine, anhydrous diethyl ether, 45 °C, 2 h, 3-bromothiophene, [1,3-bis(diphenylphosphino)propane]dichloronickel(II), 45 °C, 14.5 h, 40% [47]; b) n-butyllithium, 2,2,6,6-tetramethylpiperidine, anhydrous tetrahydrofuran, −80 °C, iodomethane, then rt, overnight, 86% [48]; c) n-butyllithium, anhydrous

• tetrahydrofuran, −5 °C, 1 h, then −78°C, trimethyl borate, then rt, overnight, 25% [49][50]. Synthesis of the soluble target structure EtH-T-DI-DTT (1): a) 32, Pd(PPh3)4, K2CO3, THF, H2O, 70 °C, 45 h, 76% [40]; b) LiOH, THF, H2O, 70 °C [15], 6 d, 91%; c) oxalyl chloride, anhydrous DMF (cat.), anhydrous CH2Cl2, rt

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

• others. Experimental General procedures and materials Tetrahydrofuran (THF) for use on vacuum line was freshly distilled from sodium/benzophenone prior to use. n-BuLi (hexane) were obtained from Energy Chemical; prior to use, its concentration was determined by titration with N-pivaloyl-o-toluidine [42

Synthesis of bis-spirocyclic derivatives of 3-azabicyclo[3.1.0]hexane via cyclopropene cycloadditions to the stable azomethine ylide derived from Ruhemann's purple

• Alexander S. Filatov,
• Olesya V. Khoroshilova,
• Anna G. Larina,
• Vitali M. Boitsov and
• Alexander V. Stepakov

Beilstein J. Org. Chem. 2022, 18, 769–780, doi:10.3762/bjoc.18.77

• tetrahydrofuran (THF), and the resulting mixture was maintained at reflux. After heating for 2 h, completion of the reaction was indicated by both the colour change of the reaction mixture and TLC (thin-layer chromatography) analysis. The proposed cycloadduct was isolated after recrystallization from methanol

• 1 and 2a into product 3a in both cases (Table 1, entries 8 and 9). Accordingly, it was concluded that tetrahydrofuran is the most appropriate solvent for carrying out the cycloaddition reaction between 1 and 2a. To reach full conversion of the reactants, it is necessary to conduct the reaction at

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

• alcohols 20 (Scheme 5) [35]. In the first step, a solution of terpenyl pinacol boronates 17 and bromochloromethane in tetrahydrofuran is mixed with n-butyllithium in n-hexane at −40 °C. By using a specifically designed, 3D-printed micromixer made from stainless steel, ultrafast mixing of both solutions is

• odor”. Alternatively, the reaction mixture is pumped to an oxidation module in which the pinacol boronates are mixed with a solution of sodium perborate in water/tetrahydrofuran to perform oxidation to the corresponding alcohols 20 at 40 °C in 60 s. In order to quench remaining oxidants, the reaction

Complementarity of solution and solid state mechanochemical reaction conditions demonstrated by 1,2-debromination of tricyclic imides

• Petar Štrbac and
• Davor Margetić

Beilstein J. Org. Chem. 2022, 18, 746–753, doi:10.3762/bjoc.18.75

• ] could be simplified by in situ generation of the catalyst. Moreover, in the debromination of norbornene imide 11, the expected Diels−Alder adduct with furan was not obtained, but compound 12 incorporating a tetrahydrofuran ring at position 2, presumably by radical reaction (Figure 2) [19][20]. We

• envisaged that the absence of solvent under mechanochemical conditions should prevent the formation of products from tetrahydrofuran and therefore allow cycloaddition to take place. Results and Discussion Reaction optimization Anthracene addition to dibromide 10 (Scheme 1) was used as the model reaction

Synthesis of a new water-soluble hexacarboxylated tribenzotriquinacene derivative and its competitive host–guest interaction for drug delivery

• Man-Ping Li,
• Nan Yang and
• Wen-Rong Xu

Beilstein J. Org. Chem. 2022, 18, 539–548, doi:10.3762/bjoc.18.56

• pentahydrate (0.93 g, 3.7 mmol) and sodium ascorbate (1.48 g, 7.4 mmol) in a cosolvent of tetrahydrofuran/water (60 mL/30 mL) was stirred vigorously under nitrogen atmosphere at 60 °C for 24 h. After the solvent was removed by rotary evaporation, a 0.1 M aqueous solution of EDTA (20 mL) was added and the

Sesquiterpenes from the soil-derived fungus Trichoderma citrinoviride PSU-SPSF346

• Wiriya Yaosanit,
• Vatcharin Rukachaisirikul,
• Souwalak Phongpaichit,
• Sita Preedanon and
• Jariya Sakayaroj

Beilstein J. Org. Chem. 2022, 18, 479–485, doi:10.3762/bjoc.18.50

• intensities of Hb-3, H-5, and Hab-15, indicating that the carboxyl moiety was α-orientated. Biosynthetically, compound 2 might be derived from compound 4 or compound 5 by oxa-Michael reaction of 7-OH to the α,β-unsaturated carboxylic acid moiety to form a tetrahydrofuran unit followed by ring opening of the

Synthesis of piperidine and pyrrolidine derivatives by electroreductive cyclization of imine with terminal dihaloalkanes in a flow microreactor

• Yuki Naito,
• Naoki Shida and
• Mahito Atobe

Beilstein J. Org. Chem. 2022, 18, 350–359, doi:10.3762/bjoc.18.39

• electrodes and subjected to the electrolytic reaction. Tetrahydrofuran (THF), which is easily oxidized, was employed as the electrolytic solvent, so the reaction at the anode (counter electrode) is thought to be preferentially caused by the oxidative decomposition of THF, and the re-oxidation of the cathodic

Synthesis and late stage modifications of Cyl derivatives

• Phil Servatius and
• Uli Kazmaier

Beilstein J. Org. Chem. 2022, 18, 174–181, doi:10.3762/bjoc.18.19

• , we treated 11 with thioacetic acid and BEt3/air in THF to give 82% of the thiol-ene click product (Scheme 4). Careful analysis of the NMR spectra revealed that the intermediately formed radical cyclized in an intramolecular 5-exo-trig fashion with the internal double bond to form a tetrahydrofuran

Ready access to 7,8-dihydroindolo[2,3-d][1]benzazepine-6(5H)-one scaffold and analogues via early-stage Fischer ring-closure reaction

• Irina Kuznetcova,
• Felix Bacher,
• Daniel Vegh,
• Hsiang-Yu Chuang and
• Vladimir B. Arion

Beilstein J. Org. Chem. 2022, 18, 143–151, doi:10.3762/bjoc.18.15

• steps as shown in Scheme 3. First, reduction of commercially available indole-2-carboxylate with lithium aluminum hydride in dry tetrahydrofuran gave (1H-indole-2-yl)methanol (10) in 89% yield. The obtained alcohol was exposed to benzoyl chloride and triethylamine to furnish benzoate 11, which was

Synthesis of new pyrazolo[1,2,3]triazines by cyclative cleavage of pyrazolyltriazenes

• Nicolai Wippert,
• Martin Nieger,
• Claudine Herlan,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2021, 17, 2773–2780, doi:10.3762/bjoc.17.187

• , failed under similar procedures. Abbreviations TFA, trifluoroacetic acid; DMSO, dimethyl sulfoxide; THF, tetrahydrofuran, TLC, thin-layer chromatography, LC–MS, liquid chromatography/mass spectrometry. Structural differences of several known (2–4) and so far unknown (5 and 6) pyrazolo[3,4-d][1,2,3]-3H