Asymmetric synthesis of fluorinated derivatives of aromatic and γ-branched amino acids via a chiral Ni(II) complex

• Maurizio Iannuzzi,
• Thomas Hohmann,
• Michael Dyrks,
• Kilian Haoues,
• Katarzyna Salamon-Krokosz and
• Beate Koksch

Beilstein J. Org. Chem. 2025, 21, 659–669, doi:10.3762/bjoc.21.52

• synthesis of alkyl iodides was investigated. A tosylate functionality was employed as a leaving group in the iodination reaction. Finally, the desired fluorinated tosylate 9 could be isolated on a gram-scale in a moderate yield of 27% (Scheme 3a). Subsequently, the iodination of the tosylate has been

Synthesis of the aggregation pheromone of Tribolium castaneum

• Biyu An,
• Xueyang Wang,
• Ao Jiao,
• Qinghua Bian and
• Jiangchun Zhong

Beilstein J. Org. Chem. 2025, 21, 510–514, doi:10.3762/bjoc.21.38

• is a destructive stored product pest. The aggregation pheromone of this pest was prepared via a new and effective strategy. The key steps include the ring-opening reaction of chiral 2-methyloxirane, the stereospecific inversion of chiral secondary tosylate, Li2CuCl4-catalyzed coupling of tosylate

• olefine (5R,9R)-12, which could be obtained through Li2CuCl4-catalyzed coupling of chiral tosylate (S)-10 with a Grignard reagent derived from (R)-1-bromo-2-methylbutane ((R)-11). The key chiral building block (S)-10 was envisaged to be prepared through a sequence of hydrolyzation, decarboxylation, borane

• -amine reduction and tosylation from diethyl (S)-2-(hex-5-en-2-yl)malonate ((S)-6). The stereocenter in geminal ester (S)-6 could be derived from (R)-2-methyloxirane ((R)-2) via a ring-opening reaction and a stereospecific inversion of the chiral secondary tosylate (R)-5. Following the similar procedure

Recent advances in organocatalytic atroposelective reactions

• Henrich Szabados and
• Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

Structure and thermal stability of phosphorus-iodonium ylids

• Andrew Greener,
• Stephen P. Argent,
• Coby J. Clarke and
• Miriam L. O’Duill

Beilstein J. Org. Chem. 2024, 20, 2931–2939, doi:10.3762/bjoc.20.245

• , with the tosylate trans to the arene in one (θ2 = 177.8) and trans to the ylid in the other (θ1 = 169.5), which suggests that this isomerisation is fast at room temperature and the position of the anion has no significant effect on the stability of these compounds. This hypothesis is further supported

Recent advances in transition-metal-free arylation reactions involving hypervalent iodine salts

• Ritu Mamgain,
• Kokila Sakthivel and
• Fateh V. Singh

Beilstein J. Org. Chem. 2024, 20, 2891–2920, doi:10.3762/bjoc.20.243

• decarboxylation of α,α-difluoro-β-keto acid esters 11 with the help of aryl(TMP)iodonium tosylates 12 in toluene at 100 °C to yield α,α-difluoroketones 13 in excellent yield (Scheme 4). The reaction proceeds via ligand exchange between the fluorinated carboxylate and the tosylate anion of the hypervalent iodine

N-Glycosides of indigo, indirubin, and isoindigo: blue, red, and yellow sugars and their cancerostatic activity

• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 2840–2869, doi:10.3762/bjoc.20.240

• an orange solid (Scheme 29) [46]. In the first step, a base-mediated aldol reaction was carried out. The corresponding alcohol was directly used as the crude product and treated with tosyl chloride, NEt3, and DMAP (stirring for 2 h at 20 °C) to give the corresponding tosylate which was further

A review of recent advances in electrochemical and photoelectrochemical late-stage functionalization classified by anodic oxidation, cathodic reduction, and paired electrolysis

• Nian Li,
• Ruzal Sitdikov,
• Ajit Prabhakar Kale,
• Joost Steverlynck,
• Bo Li and
• Magnus Rueping

Beilstein J. Org. Chem. 2024, 20, 2500–2566, doi:10.3762/bjoc.20.214

• constant voltage (CV) conditions and light irradiation under a nitrogen atmosphere. This method demonstrates broad compatibility with various functional groups and complex substrates, including alcohol, carboxylic acid, esters, alkyl chloride, and tosylate groups. Notably, the LSF of compounds such as

Multicomponent syntheses of pyrazoles via (3 + 2)-cyclocondensation and (3 + 2)-cycloaddition key steps

• Ignaz Betcke,
• Alissa C. Götzinger,
• Maryna M. Kornet and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2024, 20, 2024–2077, doi:10.3762/bjoc.20.178

• -pot process can be conducted in various solvents such as in PEG 400 [79], ionic liquids like 1-butyl-3-methylimidazolium hydroxide ((Bim)OH) [80], the nanoionic liquid 1-methylimidazolium trinitrocarbide ([[HMIM]C(NO2)3]) [81], N-methylpyridinium tosylate (NMPYT) [82], or glucose-based strong eutectic

Regioselective alkylation of a versatile indazole: Electrophile scope and mechanistic insights from density functional theory calculations

• Pengcheng Lu,
• Luis Juarez,
• Paul A. Wiget,
• Weihe Zhang,
• Krishnan Raman and
• Pravin L. Kotian

Beilstein J. Org. Chem. 2024, 20, 1940–1954, doi:10.3762/bjoc.20.170

• reactions with compound 6 afforded the N1-substituted indazole analogs 15a–q with excellent yields (>90%), except for 15m, which failed to form after multiple attempts likely due to an instability of the electrophile 14m under optimized conditions (conditions A: 1.5 equiv tosylate, 1.0 equiv 6, 2.0 equiv

• cesium carbonate (766 mg, 2.352 mmol) followed by the necessary tosylate (1.5 equiv). The resulting mixture was stirred for 2 hours at 90 °C. The mixture was poured into EtOAc (500 mL) and washed with water (100 mL) and brine. The organic layer was dried and concentrated, the obtained residue was

Novel oxidative routes to N-arylpyridoindazolium salts

• Oleg A. Levitskiy,
• Yuri K. Grishin and
• Tatiana V. Magdesieva

Beilstein J. Org. Chem. 2024, 20, 1906–1913, doi:10.3762/bjoc.20.166

• in line with the green chemistry requirements [24]. To test the assumption, the preparative oxidation of amine A1 was performed in the potentiostatic mode at 1.6 V (vs Ag/AgCl, KCl(sat.)) in a two-compartment cell in DMF; sodium tosylate was used as a supporting electrolyte. After a charge

• conditions of the potentiostatic electrolysis were the following: a two-compartment cell, a glassy carbon (GC) anode, DMF, the potential increased from 1.0 V to 1.4 V vs Ag/AgCl, KCl(sat.)), 2 F per mol of amine electricity passed, sodium tosylate (0.1 M) as a supporting electrolyte, and 2 equiv of 2.6

The Groebke–Blackburn–Bienaymé reaction in its maturity: innovation and improvements since its 21st birthday (2019–2023)

• Cristina Martini,
• Muhammad Idham Darussalam Mardjan and
• Andrea Basso

Beilstein J. Org. Chem. 2024, 20, 1839–1879, doi:10.3762/bjoc.20.162

Synthesis of polycyclic aromatic quinones by continuous flow electrochemical oxidation: anodic methoxylation of polycyclic aromatic phenols (PAPs)

• Hiwot M. Tiruye,
• Solon Economopoulos and
• Kåre B. Jørgensen

Beilstein J. Org. Chem. 2024, 20, 1746–1757, doi:10.3762/bjoc.20.153

• short distance between the electrodes, and easily reproduceable conditions. The electrochemical oxidation of phenols has been performed with platinum anodes [37][41], and carbon/platinum worked well for the oxidation of toluene dissolved in methanol with tetraethylammonium tosylate (Et4NOTs) as a

Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

• protecting group yielded the corresponding hydroxyalkynyl derivative 4. Subsequent Lindlar reduction resulted in the (Z)-alkene and a chemoselective tosylation of the primary alcohol led to the formation of tosylate 5. This intermediate underwent a stereospecific 4-exo cyclization upon exposure to iodine

Oxidative hydrolysis of aliphatic bromoalkenes: scope study and reactivity insights

• Amol P. Jadhav and
• Claude Y. Legault

Beilstein J. Org. Chem. 2024, 20, 1286–1291, doi:10.3762/bjoc.20.111

• (Scheme 3). No α-tosyloxy ketone products were observed in the crude reaction mixtures, either with catalytic or stoichiometric use of TsOH·H2O, even when the reactions were incomplete. These observations ruled out the possibility of double SN2 attack by tosylate followed by bromide. TsOH·H2O accelerates

Auxiliary strategy for the general and practical synthesis of diaryliodonium(III) salts with diverse organocarboxylate counterions

• Naoki Miyamoto,
• Daichi Koseki,
• Kohei Sumida,
• Elghareeb E. Elboray,
• Naoko Takenaga,
• Ravi Kumar and
• Toshifumi Dohi

Beilstein J. Org. Chem. 2024, 20, 1020–1028, doi:10.3762/bjoc.20.90

• triflate (TfO−) [14], tetrafluoroborate (BF4−) [15], tosylate (TsO−) [16], and others [17], has been extensively studied, as they play a key factor in the participation of iodonium salts in diverse arylation reactions. Recently, efficient syntheses of diaryliodonium(III) trifluoroacetates have been

Benzoimidazolium-derived dimeric and hydride n-dopants for organic electron-transport materials: impact of substitution on structures, electrochemistry, and reactivity

• Swagat K. Mohapatra,
• Khaled Al Kurdi,
• Samik Jhulki,
• Georgii Bogdanov,
• John Bacsa,
• Maxwell Conte,
• Tatiana V. Timofeeva,
• Seth R. Marder and
• Stephen Barlow

Beilstein J. Org. Chem. 2023, 19, 1651–1663, doi:10.3762/bjoc.19.121

• iodomethane (or methyl tosylate) to afford the benzimidazolium iodides (or tosylates), 1+I− (or 1+OTs−), which were metathesized to the corresponding hexafluorophosphates, 1+PF6−. Either I− or PF6− salt can then be converted to the corresponding 1H derivative using NaBH4 in MeOH. The PF6− salts are somewhat

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

• reacted immediately (one-pot procedure) with sodium borohydride to give 4.4. It must be noted that this sequence does not induce racemization and that 4.4 can be stored for months with 0.5% of solid KOH acting as a stabilizer [72]. Then, 4.4 was alkylated with stearyl tosylate to produce 4.5. The two

• benzylation produced 4.13. Then, the deprotection of the primary alcohol in acidic conditions allows introducing the phosphocholine polar head group by using POCl3 and the choline tosylate salt as reagents to yield 4.14. Finally, the debenzylation of the secondary alcohol and its acylation produce PAF 4.15. b

• from allyl alcohol (Figure 7) [82]. The Sharpless asymmetric epoxidation of allyl alcohol followed by tosylation produced glycidyl tosylate 7.1a (Figure 7). The reaction of palmityl alcohol (C16H33-OH) in the presence of a catalytic amount of BF3 open regio- and stereoselectively the epoxide to produce

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

Synthesis, α-mannosidase inhibition studies and molecular modeling of 1,4-imino-ᴅ-lyxitols and their C-5-altered N-arylalkyl derivatives

• Martin Kalník,
• Sergej Šesták,
• Juraj Kóňa,
• Maroš Bella and
• Monika Poláková

Beilstein J. Org. Chem. 2023, 19, 282–293, doi:10.3762/bjoc.19.24

• in two steps from known ʟ-ribitol 1 [34] in good overall yield. Next, it was converted to the C-5 deoxygenated N-benzylpyrrolidine 6 via trityl ether cleavage, tosylation of the deprotected OH group, and reduction of the tosylate 5. Hydrogenolysis of the N-benzyl group in 6 followed by a removal of

Investigation of cationic ring-opening polymerization of 2-oxazolines in the “green” solvent dihydrolevoglucosenone

• Solomiia Borova and
• Robert Luxenhofer

Beilstein J. Org. Chem. 2023, 19, 217–230, doi:10.3762/bjoc.19.21

• polymerization initiated with methyl triflate (black), methyl tosylate (red), 2-ethyl-3-methyl-2-oxazolinium triflate (blue), benzyl bromide (green) after 3 h of incubation and acyl chloride (dark red), propionyl chloride (purple) after 24 h of incubation in DLG. Peaks marked with asterisks originate from

Preparation of β-cyclodextrin-based dimers with selectively methylated rims and their use for solubilization of tetracene

• Konstantin Lebedinskiy,
• Volodymyr Lobaz and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2022, 18, 1596–1606, doi:10.3762/bjoc.18.170

• as the price of some reagents and relatively low yields. In this work, we describe a method using low-cost reactants, such as methyl tosylate and DIPEA, which provides moderate to high yields and is a reasonable alternative to the existing methods. The acetylation of compound 1 using standard

• conditions gave the secondary side peracetylated 6 in a high yield. The selective deprotection of silyl groups, yielding compound 7, was also performed standardly using BF3O·Et2O. Our new procedure is based on the methylation of this acetyl-protected β-CD 7 using a DIPEA/methyl tosylate mixture without

• mixture decreases during the first several hours due to the quaternization of DIPEA. We found that adding small portions of the base over the reaction course allows us to avoid this problem and finish the process successfully. Purifying the reaction mixture requires the removal of excess methyl tosylate

Mechanochemical halogenation of unsymmetrically substituted azobenzenes

• Dajana Barišić,
• Mario Pajić,
• Ivan Halasz,
• Darko Babić and
• Manda Ćurić

Beilstein J. Org. Chem. 2022, 18, 680–687, doi:10.3762/bjoc.18.69

• of L6–8 with N-chlorosuccinimide (NCS) gave no chlorinated product, which was also observed in the reaction of L1 with NCS (Table 2, entries 1–4) [51]. Since the monomeric monopalladated tosylate complex of azobenzene I1-I was identified as an intermediate in the solid-state bromination of L1 (Figure

•  1) [51], the analogous complexes of L6 and L7 were prepared to investigate whether the halogenation of the para-halogenated azobenzene derivatives follows the reaction pathway of the bromination of L1. The molecular structures of the isolated monopalladated tosylate complexes I6-I and I7-I solved

• from laboratory powder X-ray diffraction (PXRD) data (Figure 4 and Figures S31 and S32 in Supporting Information File 1), are similar to that of complex I1-I [51] in which the palladium center is bound to the MeCN and tosylate (OTs) via nitrogen and oxygen, respectively, and to the azobenzene via the

Mechanistic studies of the solvolysis of alkanesulfonyl and arenesulfonyl halides

• Malcolm J. D’Souza and
• Dennis N. Kevill

Beilstein J. Org. Chem. 2022, 18, 120–132, doi:10.3762/bjoc.18.13

• expanded to give a two-term Equation 2 [34][36][37], where l is the sensitivity to changes in N, which is a measure of solvent nucleophilicity. The original N scale was based on the specific rates of solvolysis of methyl tosylate [38] but, with this as the standard, there is a significant problem in

• fluorosulfates [76]. In discussing the k4OE/k97TFE ratios, a good starting point is with the bridgehead-substituted 1-adamantyl chlorides, where a rear side SN2 process is impossible, with a value for the ratio of 0.83. The ratio raises to 1.38 for the tosylate but such variations are to be expected because

Stepwise PEG synthesis featuring deprotection and coupling in one pot

• Logan Mikesell,
• Dhananjani N. A. M. Eriyagama,
• Yipeng Yin,
• Bao-Yuan Lu and
• Shiyue Fang

Beilstein J. Org. Chem. 2021, 17, 2976–2982, doi:10.3762/bjoc.17.207

• heating was to prevent the removal of the base-labile protecting group in 3 by the excess strong base by allowing the excess base to be consumed selectively via β-elimination of the tosylate in 1. The product of premature removal of the base-labile protecting group – an alkoxide – would complicate the

• reaction, while the product of β-elimination of the tosylate – a vinyl ether – is inert under the reaction conditions. Compounds 3a–l were subjected to the study. All the compounds except 3h were found to be stable under the coupling conditions while product 5 was formed as indicated by TLC analysis

• mixture was cooled to −78 °C, and then the monomer solution was added and the reaction mixture was warmed to room temperature slowly before heating to 60 °C. The careful manipulation of the temperature allowed the excess base to be selectively consumed via β-elimination of the tosylate of the monomer

Synthesis and antimicrobial activity of 1H-1,2,3-triazole and carboxylate analogues of metronidazole

• Satya Kumar Avula,
• Syed Raza Shah,
• Khdija Al-Hosni,
• Muhammad U. Anwar,
• Rene Csuk,
• Biswanath Das and
• Ahmed Al-Harrasi

Beilstein J. Org. Chem. 2021, 17, 2377–2384, doi:10.3762/bjoc.17.154

• group. The first step was initiated by the protection of the primary hydroxy group of metronidazole (1) with p-toluenesulfonyl chloride in dry DCM in the presence of triethylamine at 0 °C to room temperature. The reaction afforded the desired metronidazole tosylate 2 in high yield (96%) [17]. In the

• next step, the metronidazole tosylate 2 under treatment with NaN3 in DMF at 70 °C afforded the corresponding metronidazide 3 in 88% yield [18]. The 1H NMR spectrum of metronidazide 3 showed a singlet at δ 7.93 for the 1H-imidazole proton. Two triplet signals at δ 4.40 and δ 3.74 were assigned to four