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

• ” and only “slightly fruity” [9]. Kappe and co-workers disclosed an access to both odorants in a two-step synthesis (Scheme 1) [24]. In the first step, 4-aryl-3-buten-2-ones 3 and 4 are prepared via aldol condensation of the corresponding aldehydes 1 and 2 and acetone in 78–90% yield with a productivity

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

• was collected by suction filtration, and washed sequentially with water, dichloromethane, and acetone to give compound 3 as a colorless solid (0.37 g, 85%). Mp 59.6–60.7 °C; 1H NMR (400 MHz, DMSO-d6, 25 °C) δ 8.19 (br s, 6H), 7.38 (br s, 6H), 5.26 (br s, 12H), 5.21 (br s, 12H), 4.23 (s, 3H), 1.60 (s

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

• macrocycle (S)-61-Me22+. Only the first association constant (K11) is given. aIn acetone-d6/D2O 98:2. bIn acetone-d6/D2O 99:1. Synthesis of Beer´s [3]rotaxane (S)-68. Association constants of different anions (used as the Bu4N+-salts) to the [2]rotaxane (S)-68 and axle (S)-65. Only the first association

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

• mixture of acetone/hexane 1:4 to afford five subfractions (B3E1–B3E5). Subfraction B3E2 (5.1 mg) was purified using the same procedure as fraction A4 to afford compound 7 (2.8 mg). Subfraction B3I (454.1 mg) was separated using the same procedure as subfraction A4F6J to provide seven subfractions (B3I1

• mg) was then washed with acetone to afford compound 5 (3.7 mg). Trichocitrinovirene A (1): Colorless gum; +46.1 (c 0.67, MeOH); UV (MeOH) λmax, nm (log ε): 210 (3.32); ECD (MeOH, c 0.0008) λmax, nm (Δε): 227 (+4.3); IR (neat) νmax: 3336, 1684, 1649 cm−1; 1H and 13C NMR (CD3OD) see Table 1; HRMS–ESI

The asymmetric Henry reaction as synthetic tool for the preparation of the drugs linezolid and rivaroxaban

• Martin Vrbický,
• Karel Macek,
• Jaroslav Pochobradský,
• Jan Svoboda,
• Miloš Sedlák and
• Pavel Drabina

Beilstein J. Org. Chem. 2022, 18, 438–445, doi:10.3762/bjoc.18.46

• intermediate 11 was accompanied with simultaneous cleavage of the Boc group. However, attempts of achieving a selective deacetalation of 11 by the treatment with several reagents (e.g., I2/acetone [15], FeCl3·6H2O/acetaldehyde [16], Ce(OTf)3 [17]) were unsuccessful. Therefore, an alternative synthesis [18] was

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

• (Scheme 2, method B). Finally, the use of H2O2 thermal decomposition in acetone with catalytic methanesulfonic acid, led to compounds 10 and 18 in 47% yield with 86:14 ratio (Scheme 2, method C). In all cases, the monomethylation was not selective and even at partial conversions of naphthoquinone

Four bioactive new steroids from the soft coral Lobophytum pauciflorum collected in South China Sea

• Di Zhang,
• Zhe Wang,
• Xiao Han,
• Xiao-Lei Li,
• Zhong-Yu Lu,
• Bei-Bei Dou,
• Wen-Ze Zhang,
• Xu-Li Tang,
• Ping-Lin Li and
• Guo-Qiang Li

Beilstein J. Org. Chem. 2022, 18, 374–380, doi:10.3762/bjoc.18.42

• subjected to silica gel column chromatography (CC) eluted with two gradient systems, PE/acetone (1:0 to 1:1) and subsequently CH2Cl2/MeOH (15:1 to 1:1) to afford 8 fractions. Fraction 4 (14.6 g) was split (chromatographed on) by silica gel eluting with a gradient of PE/acetone (30:1 to 1:1) to give three

• subfractions (F41–F43). Subfraction F41 (2.1 g) was chromatographed over silica gel column (PE/acetone, 50:1 to 2:1) to give seven subfractions (F411–F417), F411 (330 mg) was purified by semi-preparative HPLC (ODS, 5 µm, 250 × 10 mm; methanol/water, 95:5, v/v; 2.0 mL/min) to afford compound 4 (2.3 mg), 5 (4.7

A Se···O bonding catalysis approach to the synthesis of calix[4]pyrroles

• Qingzhe Tong,
• Zhiguo Zhao and
• Yao Wang

Beilstein J. Org. Chem. 2022, 18, 325–330, doi:10.3762/bjoc.18.36

• between ketones and pyrrole might take place to give calix[4]pyrrole derivatives under catalysis of a selenide catalyst. In the absence of a catalyst, no reaction took place. Indeed, even in presence of 5 mol % representative catalyst Ch1 [44], the condensation reaction between acetone and pyrrole worked

• efficiently at room temperature. We note that this reaction did not stop at a bis(pyrrole)methane stage, but consecutive condensations between four molecules of acetone and four molecules of pyrrole took place to give calix[4]pyrrole 2a in 91% yield after 4 h (Scheme 2). Further investigations revealed that

• changing acetone to pentan-3-one, the chemical yield decreased significantly and product 2b was obtained in 42% yield. Using cyclopentanone as a reactant, product 2c was obtained in 45% yield. Moreover, cyclohexanone and cycloheptanone could also be used as effective reactants, and products 2d and 2e were

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

• steps. In 2017, Lesyk and co-workers observed the indole C3 regioselective ring closure in the reaction between 4-aminoindoles 7 and acetone in the presence of hydrochloric acid as a catalyst (Scheme 4) [13]. Based on NMR spectroscopy and X-ray crystallographic analysis, the products were unambiguously

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

• derivative 7 was generated in 79% yield by treatment of amine 6 with chloroacetyl chloride. Next, the aminoacetyl group in 7 was benzyl-protected to give 8 in 88% yield. Halogen exchange reaction using excess sodium iodide in acetone gave the desired iodo-alkyl derivative 9 in 79% yield. Lastly, our attempt

Green synthesis of C5–C6-unsubstituted 1,4-DHP scaffolds using an efficient Ni–chitosan nanocatalyst under ultrasonic conditions

• Soumyadip Basu,
• Sauvik Chatterjee,
• Suman Ray,
• Suvendu Maity,
• Prasanta Ghosh,
• Asim Bhaumik and
• Chhanda Mukhopadhyay

Beilstein J. Org. Chem. 2022, 18, 133–142, doi:10.3762/bjoc.18.14

• . We mainly focused on the synthesis under green aspects and towards a high product diversity. We initially chose three green solvents with a relatively low boiling point, ethanol, water, and acetone, respectively, as a reaction medium. A series of reactions was examined in these solvents, using an

• added to the mixture, and the solid catalyst was separated from the mixture by an external magnet. The recovered catalyst was washed with water and acetone, dried in a desiccator, and stored for a consecutive reaction. The crude products were obtained by evaporation of the solvent in a rotary evaporator

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

• solvent composition. In a very early 1927 study [4] of the solvolyses of benzenesulfonyl chloride (C6H5SO2Cl) and its p-methyl and m-nitro derivatives, solvolyzing in 50% acetone/50% water (v/v) at 25.0 °C, it was found that the differences in specific rates were quite small, at 0.0106 min−1 for the p

• of the review, the study is of solvolysis mechanisms and the reactions involve the solvolyses of a series of para and meta-ring-substituted substrates. Applying the Hammett equation to the rate measurements of Berger and Oliver [4], we arrive, in 50% water/50% acetone (v/v) at a reaction constant ρ

• and Scott showed [9] that in 50% acetone/50% water at 0.5 °C, a hydroxide ion was about 106 times more reactive than a water molecule towards benzenesulfonyl chloride. Also, for the same solvent, at 25.0 °C, they found [10] that the fluoride, with a considerably stronger carbon–halogen bond, reacted

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

Recent advances and perspectives in ruthenium-catalyzed cyanation reactions

• Thaipparambil Aneeja,
• Cheriya Mukkolakkal Abdulla Afsina,
• Padinjare Veetil Saranya and
• Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 37–52, doi:10.3762/bjoc.18.4

• the oxidative cyanation of tertiary amines using Ru as the catalyst (Scheme 11) [35]. In this reaction, the comparatively safer acetone cyanohydrin was utilized as the cyanating agent. Better yields of products were obtained for both electron-rich and electron-deficient tertiary amines. Cyclic amines

• such as piperidine, tetrahydroisoquinoline derivatives, and pyrrolidine were also tolerated well in this reaction. The use of the non-toxic and inexpensive acetone cyanohydrin makes this method more advantageous compared to the known methods. 2 Cyanation of arenes and heteroarenes 2.1 Cyanation of

• complexes. From our discussion it is evident that the most commonly used cyanating reagents include highly toxic compounds such as K4[Fe(CN)6], NaCN, CuCN, TMSCN etc. However, some of the reported works involve the use of safer and greener cyanation sources like NCTS, acetone cyanohydrin, ethyl cyanoformate

A photochemical C=C cleavage process: toward access to backbone N-formyl peptides

• Haopei Wang and
• Zachary T. Ball

Beilstein J. Org. Chem. 2021, 17, 2932–2938, doi:10.3762/bjoc.17.202

• . Unfortunately, no products other than the formyl compound were isolated after photocleavage of compound 1 or 6 in acidic conditions. Instead, when irradiation of alkenyl amide 1 was conducted in acetone, crude NMR analysis indicated the appearance of product 8 as well as new peaks in the aromatic region

• 1 in acetone. Preparation and hydrolysis kinetics (inset) of N-formyl product 11. Dashed line: first-order decay fit used in calculating the rate constant. Proposed mechanism for the formation of aldehyde 3 and N-formyl product 8. Supporting Information Supporting Information File 280: Experimental

Total synthesis of the O-antigen repeating unit of Providencia stuartii O49 serotype through linear and one-pot assemblies

• Tanmoy Halder and
• Somnath Yadav

Beilstein J. Org. Chem. 2021, 17, 2915–2921, doi:10.3762/bjoc.17.199

• (TCCA) in aqueous acetone [51] resulting in compound 11. Treatment of compound 11 with trichloroacetonitrile and DBU in dry DCM resulted in the formation of the desired trichloroacetimidate donor 12 in 93% yield (Scheme 4). The first stage of the one-pot synthesis was carried out using donor 12 and

Highly stereocontrolled total synthesis of racemic codonopsinol B through isoxazolidine-4,5-diol vinylation

• Lukáš Ďurina,
• Anna Ďurinová,
• František Trejtnar,
• Ľuboš Janotka,
• Lucia Messingerová,
• Jana Doháňošová,
• Ján Moncol and
• Róbert Fischer

Beilstein J. Org. Chem. 2021, 17, 2781–2786, doi:10.3762/bjoc.17.188

• reported 2-chloropyridine reduced the product yield slightly to 60% [25]. The subsequent epoxidation of 9 with in situ-generated DMDO (a combination of oxone and NaHCO3 in acetone/water) provided isoxazolidinyl epoxide 10 in almost quantitative yield as a sole trans isomer (dr > 95:5). Finally, the acid

• -catalyzed hydrolysis of 10 with concentrated hydrochloric acid in acetone/water afforded diol 3 in excellent 93% yield. The crystallization of the crude product from a hexanes/CH2Cl2 mixture led to the preferential formation of the thermodynamically more stable 4,5-cis isomer (determined on the basis of a

• rt, 16 h, 68%; (c) oxone, NaHCO3, acetone/H2O 3:2, 0 °C to rt, 80 min, 99%; (d) HCl (37 wt % in H2O), acetone/H2O 4:1, 0 °C, 30 min, 93%. Synthesis of final pyrrolidines (±)-1 and (±)-2. Reagents and conditions: (a) vinyl-MgBr, CeCl3, THF, 0 °C to rt, 16 h, 73%; (b) Zn dust, AcOH, 40 °C, 24 h, 85

Isolation and characterization of new phenolic siderophores with antimicrobial properties from Pseudomonas sp. UIAU-6B

• Emmanuel T. Oluwabusola,
• Olusoji O. Adebisi,
• Fernando Reyes,
• Kojo S. Acquah,
• Mercedes De La Cruz,
• Larry L. Mweetwa,
• Joy E. Rajakulendran,
• Digby F. Warner,
• Deng Hai,
• Rainer Ebel and
• Marcel Jaspars

Beilstein J. Org. Chem. 2021, 17, 2390–2398, doi:10.3762/bjoc.17.156

• nitrogen stream. The hydrolysates were treated with 1 M NaHCO3 solution (20 µL) and 1% solution of ʟ-FDAA (Marfey's reagent, 1-fluoro-2-4-dinitrophenyl-5-ʟ-alanine amide) in acetone (40 µL). The reaction mixtures were gently heated at 40 °C for 1 h, after which the solutions were neutralized by the

A visible-light-induced, metal-free bis-arylation of 2,5-dichlorobenzoquinone

• Pieterjan Winant and
• Wim Dehaen

Beilstein J. Org. Chem. 2021, 17, 2315–2320, doi:10.3762/bjoc.17.149

• reaction site) of the aryldiazonium salt were required to obtain significant conversion of the starting material. Changing the solvent to acetone significantly increased the reaction yield, while dichloromethane as a solvent only resulted in trace amounts of the product (Table 1, entries 2 and 3). Due to

Transition-metal-free intramolecular Friedel–Crafts reaction by alkene activation: A method for the synthesis of some novel xanthene derivatives

• Tülay Yıldız,
• İrem Baştaş and
• Hatice Başpınar Küçük

Beilstein J. Org. Chem. 2021, 17, 2203–2208, doi:10.3762/bjoc.17.142

• 78% (Table 1, entry 2). The second-best yield was 65% when FeCl3·6H2O was used (Table 1, entry 1). Then the solvent was investigated. Toluene, methyl alcohol, ethyl acetate, THF, DMF, dichloromethane, chloroform, acetone, and acetonitrile were tested as solvents. As a result, it was determined that

Preparation of mono-substituted malonic acid half oxyesters (SMAHOs)

• Tania Xavier,
• Sylvie Condon,
• Christophe Pichon,
• Erwan Le Gall and
• Marc Presset

Beilstein J. Org. Chem. 2021, 17, 2085–2094, doi:10.3762/bjoc.17.135

• route where the substituent was introduced prior to the protection step. Commercially available substituted malonic acids 9 were first protected with acetone under acid conditions [46], and the desired intermediates 7 were simply isolated after aqueous work-up, usually in good yields (Table 3). The

2,4-Bis(arylethynyl)-9-chloro-5,6,7,8-tetrahydroacridines: synthesis and photophysical properties

• Najeh Tka,
• Mohamed Adnene Hadj Ayed,
• Mourad Ben Braiek,
• Mahjoub Jabli,
• Noureddine Chaaben,
• Kamel Alimi,
• Stefan Jopp and
• Peter Langer

Beilstein J. Org. Chem. 2021, 17, 1629–1640, doi:10.3762/bjoc.17.115

• cooled to room temperature and concentrated to give a slurry. The residue was diluted with dichloromethane, neutralized with aqueous NaHCO3, and washed with brine. The organic layer was dried over anhydrous K2CO3 and concentrated to afford a yellow solid. It was recrystallized from acetone to give 2 as

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

• complex (ʟ-proline-MCM-41-CuCl) was obtained by the reaction of ʟ-proline-MCM-41 with CuCl in acetone at mild temperature (Scheme 21) [51]. A possible mechanism for this reaction is shown in Scheme 22. Initially, copper(I)-substituted acetylide intermediate 70 is produced via the reaction of copper

Breaking paracyclophane: the unexpected formation of non-symmetric disubstituted nitro[2.2]metaparacyclophanes

• Suraj Patel,
• Tyson N. Dais,
• Paul G. Plieger and
• Gareth J. Rowlands

Beilstein J. Org. Chem. 2021, 17, 1518–1526, doi:10.3762/bjoc.17.109

• , 143.4, 137.0, 132.1, 131.0, 129.9, 129.3, 129.1, 69.6, 42.9, 34.5, 33.1, 31.1; 1H NMR (700 MHz, acetone-d6) δ (ppm) 7.45 (d, J = 7.9 Hz, 1H, H-13), 7.15 (dd, J = 1.6, 7.7 Hz, 1H, H-12), 6.70 (dd, J = 1.6, 7.7 Hz, 1H, H-15), 6.56 (dd, J = 1.7, 7.7 Hz, 1H, H-16), 6.47 (dd, J = 2.9, 10.0 Hz, 1H, H-5), 5.87

• , acetone-d6) δ (ppm) 186.8, 147.0, 146.6, 143.1, 137.7, 130.7, 130.0, 198.8, 194.4, 128.3, 128.3, 68.6, 43.2, 34.1, 32.8, 30.8; HRMS-EI m/z: [M + Na]+ calcd for C16H16O2Na, 263.1043; found, 263.1054; ESIMS (m/z): [M]+ 241, 224, 118, 104; IR: 3386, 2918, 2849, 1651, 1622, 1261, 1020, 829, 813 cm−1; mp: 206

Total synthesis of ent-pavettamine

• Memory Zimuwandeyi,
• Manuel A. Fernandes,
• Amanda L. Rousseau and
• Moira L. Bode

Beilstein J. Org. Chem. 2021, 17, 1440–1446, doi:10.3762/bjoc.17.99

• that the new route doubled the overall yield to 16% for a similar number of steps. The specific optical rotation for 4 of +28.1° in acetone was comparable to that obtained previously [1]. Single crystal X-ray analysis of compound 4 (Figure 3), further confirmed the identity and stereochemistry of the

• compound 9. Stereoselective reduction of intermediate 8 as key step towards intermediate 4. Reaction conditions: a) i) ZnCl2, rt, 2 h; ii) DIBALH, THF, −78 °C to rt, 2 h, 87%; b) TBAF, THF, 0 °C, 4 h, 87%; c) 5% p-TsOH, 2,2-dimethoxypropane, acetone, rt, 1 h, 86%. Synthesis of the C5 fragments from