Enolates ambushed – asymmetric tandem conjugate addition and subsequent enolate trapping with conventional and less traditional electrophiles

• Péter Kisszékelyi and
• Radovan Šebesta

Beilstein J. Org. Chem. 2023, 19, 593–634, doi:10.3762/bjoc.19.44

• properties. In several cases the α-SCF3-substituted ketones 44 were isolated in good yields and enantioselectivities but with low diastereoselectivities. Even though no asymmetric catalyst was involved, Kawano et al. recently demonstrated an attractive one-pot procedure for preparing complex bicyclic and

• developed a copper/Rev-Josiphos-catalyzed asymmetric conjugate addition of Grignard reagents to 2-methylcyclopentenone (78), which provided 2,3-disubstituted cyclopentanones in high yields and enantiomeric purities [53]. The one-pot alkylation reaction of the in situ formed magnesium enolate with alkylating

• Phebox-based rhodium complex (C3) to catalyze the tandem conjugate addition of a terminal alkene followed by reacting the bicyclic dienol silyl ether intermediate with Michael acceptors in a one-pot procedure (Scheme 50) [92]. The bridged cyclic products 196a,b, formed by a double Michael addition

Mechanochemical solid state synthesis of copper(I)/NHC complexes with K₃PO₄

• Ina Remy-Speckmann,
• Birte M. Zimmermann,
• Mahadeb Gorai,
• Martin Lerch and
• Johannes F. Teichert

Beilstein J. Org. Chem. 2023, 19, 440–447, doi:10.3762/bjoc.19.34

• of green chemistry. Syntheses via mechanochemical methods offer elegant and atom-economic alternatives to liquid state synthesis approaches [33][34][35][36][37][38][39][40][41][42][43]. In accordance with the in situ transmetallation route in liquid state synthesis, a one-pot two-step procedure in a

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

• Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

• subunits. Bryden and Boyle [29] presented a mild and facile one-pot synthesis of meso-substituted zinc(II) azido-porphyrin 39a–c in excellent yield by using a diazo-transfer reagent and utilized it for the preparation of 1,2,3-triazole-linked porphyrin conjugates 40a,b using copper(I)-catalyzed click

Synthesis and reactivity of azole-based iodazinium salts

• Thomas J. Kuczmera,
• Annalena Dietz,
• Andreas Boelke and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2023, 19, 317–324, doi:10.3762/bjoc.19.27

• imidazoiodaziniums, we show highly delicate post-oxidation functionalizations retaining the hypervalent iodine center. Keywords: building block; heterocycles; hypervalent compounds; iodonium salts; one-pot synthesis; Introduction The chemistry of hypervalent iodine compounds, in particular aryl-λ3-iodanes, is

• reactivity and utility in XB catalysis. We also established one-pot methods for generating six-membered carbon-, oxygen-, and nitrogen-bridged iodonium salts, such as the iodazinium triflate 3 [32][33]. Based on these promising findings, we further wanted to elaborate this chemistry and herein we present the

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

An efficient metal-free and catalyst-free C–S/C–O bond-formation strategy: synthesis of pyrazole-conjugated thioamides and amides

• Shubham Sharma,
• Dharmender Singh,
• Sunit Kumar,
• Vaishali,
• Rahul Jamra,
• Naveen Banyal,
• Deepika,
• Chandi C. Malakar and
• Virender Singh

Beilstein J. Org. Chem. 2023, 19, 231–244, doi:10.3762/bjoc.19.22

• an operationally simple one-pot procedure for the preparation of highly diversified thioamide and amide-linked pyrazole analogues. Results and Discussion Initially, the synthesis of pyrazole C-3/4/5 carbaldehydes and 4-iodopyrazole-3-carbaldehydes was achieved by employing the recently reported

• -carbaldehyde 1, morpholine (C) and elemental sulfur under the standard reaction conditions as depicted in Scheme 5. It was noticed that this one-pot operation was completed within 2.5 hours and smoothly furnished the desired product, (5-(4-fluorophenyl)-1-phenyl-1H-pyrazol-3-yl)(morpholino)methanethione (1C

• for the construction of biologically interesting highly diversified pyrazole-linked thioamide and amide conjugates has been developed. The pyrazole C-3/4/5-tethered thioamide conjugates were prepared via a one-pot reaction between highly diversified pyrazole carbaldehydes, cyclic secondary amines, 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

• configuration of each enantiomer was determined by single-crystal X-ray analysis. In addition, a one-pot synthesis of (±)-incarviditone has been achieved from rac-rengyolone by using KHMDS as a base. We have also assessed the anticancer activity of all the synthesized compounds in breast cancer cells

• ). The formation of (±)-incarvilleatone (1), perhaps due to RC dimerized product (±)-4, first undergoes oxa-Michael followed by aldol reaction in one-pot. The aldol reaction take place with intermediate 5 in basic medium due to the close proximity of the two carbonyl groups. Finally, the structure of

• achieved the total synthesis of (±)-incarvilleatone (1) starting from rac-rengyolone (3) through accelerated RC intermolecular dimerization catalyzed by TBAF to synthesize a heterochiral dimerized product (±)-4, followed by a one-pot oxa-Michael and aldol reaction sequence using KHMDS as a base. The

Sequential hydrozirconation/Pd-catalyzed cross coupling of acyl chlorides towards conjugated (2E,4E)-dienones

• Benedikt Kolb,
• Daniela Silva dos Santos,
• Sanja Krause,
• Anna Zens and
• Sabine Laschat

Beilstein J. Org. Chem. 2023, 19, 176–185, doi:10.3762/bjoc.19.17

• substituents in the one-pot reaction and showed that regardless of the substitution pattern, the reactions lead to the stereoselective formation (≥95% (2E,4E)) of the respective dienones under mild conditions. It was found that enynes with alkyl chains gave higher yields than the corresponding aryl-substituted

Total synthesis of insect sex pheromones: recent improvements based on iron-mediated cross-coupling chemistry

• Eric Gayon,
• Guillaume Lefèvre,
• Olivier Guerret,
• Adrien Tintar and
• Pablo Chourreu

Beilstein J. Org. Chem. 2023, 19, 158–166, doi:10.3762/bjoc.19.15

• . (7E,9Z)-Dodeca-7,9-dien-1-yl acetate (3), the sex pheromone of European grapevine moth (Lobesia botrana), was thus obtained at a 14 g scale, with an overall 85% yield for the one-pot sequence involving the iron-catalyzed cross coupling followed by acetylation with Ac2O (Scheme 4b) [21]. Illustrating

Organophosphorus chemistry: from model to application

• György Keglevich

Beilstein J. Org. Chem. 2023, 19, 89–90, doi:10.3762/bjoc.19.8

• . elaborated a Lewis acid-catalyzed one-pot synthesis of phosphinates and phosphonates staring from pyridinecarboxaldehydes and diarylphosphine oxides [2]. This protocol is the analogy of the Pudovik reaction, followed by the phospha-Brook rearrangement applied mainly for the synthesis of phosphoric ester

NaI/PPh₃-catalyzed visible-light-mediated decarboxylative radical cascade cyclization of N-arylacrylamides for the efficient synthesis of quaternary oxindoles

• Dan Liu,
• Yue Zhao and
• Frederic W. Patureau

Beilstein J. Org. Chem. 2023, 19, 57–65, doi:10.3762/bjoc.19.5

• reactions constitute a powerful synthetic approach to construct multiple C–C or C–X bonds in one pot. As such, these tend to allow facile access to many complex natural molecules and drugs [1][2][3][4][5][6]. Recently, radical-initiated cascade cyclizations involving acrylamides have attracted considerable

Two-step continuous-flow synthesis of 6-membered cyclic iodonium salts via anodic oxidation

• Julian Spils,
• Thomas Wirth and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2023, 19, 27–32, doi:10.3762/bjoc.19.2

• also been investigated as useful building blocks for the synthesis of larger diaryl-based molecules, (hetero)aromatic tricyclic systems, or new aryl-moieties [24][25]. Most methods that generate DIS utilize iodoarenes as starting materials [26][27]. In these one-pot procedures, iodoarenes react with

• , we improved the formation of iodoarenes through a Brønsted acid-mediated Friedel–Crafts reaction followed by an oxidative cyclization to form the desired CDIS 1 (Scheme 1A). This one-pot approach is based on ortho-iodinated benzyl alcohols as starting materials. It allows access to a variety of

• alcohols as a solvent [37][38]. Therefore, we attempt to transfer our already established one-pot procedure towards CDIS 1 into a multi-step electrochemical flow process, improving reaction times, atom economy, and scalability (Scheme 1C). Results and Discussion We initially investigated the second step of

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

• deprotonation of 2-(α’-methoxy-γ-pyrone)-1,3-dithiane. The resulting vinylogous enolate intermediate was trapped with the electrophile 3, amounting to the one-pot preparation of compound 4, having a masked carbonyl function connecting both key fragments [27][28]. Isolated and characterized by Schmitz [17], the

• lithiocyclopentadiene and the enolate intercepted with an alkylating reagent to build the quaternary carbon of 6b (Scheme 2b). This one-pot procedure was reminiscent of our previous study describing the addition of an allylic carbanion, generated from allylstannane with n-BuLi, to 2 which was followed by the addition

• was carried out through a two-step sequence including dihydroxylation (K2OsO4·H2O, 90% yield) of 8 and oxidative cleavage (NaIO4, 91% yield) of the diol intermediate. Note that both ozonolysis and the one-pot Lemieux–Johnson oxidative cleavage process of 8 led instead to methyl ketone 11 in a

Total synthesis of grayanane natural products

• Nicolas Fay,
• Rémi Blieck,
• Cyrille Kouklovsky and
• Aurélien de la Torre

Beilstein J. Org. Chem. 2022, 18, 1707–1719, doi:10.3762/bjoc.18.181

• group on C6 was introduced after cyclopropane ring-opening, ketone protection, epoxidation and reductive ring-opening of the resulting epoxide. A one-pot β-keto phosphonate formation/Horner–Wadsworth–Emmons reaction with formaldehyde afforded 38, a precursor for the key oxidative dearomatization-induced

• synthetic route based on a convergent strategy to accomplish the synthesis of principinol E, grayanotoxin III and rhodomollein XX [34]. The key steps include i) a tandem reaction combining organocatalytic Mukaiyama aldol and intramolecular Hosomi–Sakurai reactions in a one-pot manner; ii) a 7-membered

• oxygen ene reaction involving the electron-rich olefin allowed the formation of an aldehyde, which was directly cleaved by an iridium-catalyzed deformylation, affording 52 in one-pot [36]. Deprotonation with KHMDS allowed the formation of an electron-rich diene which could again react with singlet oxygen

Redox-active molecules as organocatalysts for selective oxidative transformations – an unperceived organocatalysis field

• Elena R. Lopat’eva,
• Igor B. Krylov,
• Dmitry A. Lapshin and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2022, 18, 1672–1695, doi:10.3762/bjoc.18.179

• biomimetic oxidation of benzyl alcohols was developed using o-naphthoquinone [129] (Scheme 28). The reaction shows regioselectivity toward benzylic alcohol oxidation. This process could be included in one-pot synthesis strategies. The key step of the reaction is a 1,5-hydrogen transfer (the suggested

• derivatives were formed, which were reduced to amines in the second step (one pot) on a mercury cathode. The mercury cathode can be replaced by a carbon cathode, however, the yields are lower in this case [130]. Dioxirane and oxaziridine catalysis In dioxirane or oxaziridine catalysis, the nucleophilic attack

A novel spirocyclic scaffold accessed via tandem Claisen rearrangement/intramolecular oxa-Michael addition

• Anastasia Vepreva,
• Alexander Yanovich,
• Dmitry Dar’in,
• Grigory Kantin,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1649–1655, doi:10.3762/bjoc.18.177

• phenolic O–H bond, the Claisen rearrangement and the base-catalyzed cyclization to the spirocyclic product, we experimented with attempts to perform all three steps in a one-pot format. This gave inferior results in terms of product yield and purity. The best result was obtained by performing the Rh(II

• )-catalyzed insertion first, purifying the respective product 5 and then engaging it in the sequential Claisen rearrangement cyclization reactions performed in one-pot format. To expand the scope of the newly discovered transformations, several products of the Rh(II)-catalyzed O–H insertions 5 were

• ]. Similarly, electron-donating groups (such as 4-methoxy) in the arylidene portion of 1 complicated the course of the reaction. Having amassed a sizable arsenal of O–H insertion products 5a–n, we proceeded to study their behavior in the two-step, one-pot sequence of the Claisen rearrangement/intramolecular

A novel bis-triazole scaffold accessed via two tandem [3 + 2] cycloaddition events including an uncatalyzed, room temperature azide–alkyne click reaction

• Ksenia Malkova,
• Andrey Bubyrev,
• Vasilisa Krivovicheva,
• Dmitry Dar’in,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1636–1641, doi:10.3762/bjoc.18.175

• intermediate before the click reaction was established by 1H NMR analysis of the reaction mixture). However, the product of this two-step, one-pot reaction (19) was isolated in respectable 61% yield. The structure of compound 19 was confirmed by the single-crystal X-ray analysis which demonstrated that the

One-pot double annulations to confer diastereoselective spirooxindolepyrrolothiazoles

• Juan Lu,
• Bin Yao,
• Desheng Zhan,
• Zhuo Sun,
• Yun Ji and
• Xiaofeng Zhang

Beilstein J. Org. Chem. 2022, 18, 1607–1616, doi:10.3762/bjoc.18.171

• 10.3762/bjoc.18.171 Abstract A novel four-component reaction in one pot as an atom- and step-economic process was developed to synthesize diastereoselectively spirooxindolepyrrolothiazoles through sequential N,S-acetalation of aldehydes with cysteine and decarboxylative [3 + 2] cycloaddition with olefinic

• nitrogen-based heterocycles, such as multicomponent reactions (MCRs) [18][19][20][21][22][23], one-pot cascade reactions [24][25][26][27][28][29][30][31][32] as good examples of PASE synthesis. We have reported a series of multicomponent reactions, like Groebke–Blackburn–Bienayme for making BET inhibitors

• one-pot reactions were also developed by Zhang using the 4-aminoquinoline synthesis, for example, in amino acids(esters)-based [3 + 2] cycloadditions [38][39][40][41][42][43][44][45][46][47][48] and in the synthesis of pyrrolidine-containing systems [49][50][51][52][53][54][55][56][57][58][59

Functionalization of imidazole N-oxide: a recent discovery in organic transformations

• Koustav Singha,
• Imran Habib and
• Mossaraf Hossain

Beilstein J. Org. Chem. 2022, 18, 1575–1588, doi:10.3762/bjoc.18.168

• either one-pot or multistep reaction processes. Here, substrate scope and proposed mechanistic pathways of the different methodologies are summarized in detail. We hope that this review will provide researchers and scientists an idea on the works related to imidazole N-oxides currently going on and to do

• chloride and bromide where bromination occurred at higher rate, N-tosylpyridinium halide was the acylating agent in both cases. In 2017, M. Hossain and co-workers suggested a quite unique one-pot deoxygenative chlorination reaction procedure of 2-unsubstituted imidazole N-oxides using oxalyl chloride as

Cyclometalated iridium complexes-catalyzed acceptorless dehydrogenative coupling reaction: construction of quinoline derivatives and evaluation of their antimicrobial activities

• Hongling Shui,
• Yuhong Zhong,
• Renshi Luo,
• Zhanyi Zhang,
• Jiuzhong Huang,
• Ping Yang and
• Nianhua Luo

Beilstein J. Org. Chem. 2022, 18, 1507–1517, doi:10.3762/bjoc.18.159

• Abstract The acceptorless dehydrogenative coupling (ADC) reaction is an efficient method for synthesizing quinoline and its derivatives. In this paper, various substituted quinolines were synthesized from 2-aminobenzyl alcohols and aryl/heteroaryl/alkyl secondary alcohols in one pot via a cyclometalated

• . In addition, Aravinda's group [11] prepared 3-(1,3-dioxolan-2-yl)benzo[h]quinolines containing thiol and selenol groups in one pot by microwave irradiation, and tested the antibacterial activity of the compounds. The results showed that the antibacterial effect of some compounds was better than

One-pot synthesis of 2-arylated and 2-alkylated benzoxazoles and benzimidazoles based on triphenylbismuth dichloride-promoted desulfurization of thioamides

• Arisu Koyanagi,
• Yuki Murata,
• Shiori Hayakawa,
• Mio Matsumura and
• Shuji Yasuike

Beilstein J. Org. Chem. 2022, 18, 1479–1487, doi:10.3762/bjoc.18.155

• with various carbonyl compounds, such as carboxylic acid derivatives or aldehydes [6][7][8][9]. These classic reactions require harsh conditions, such as using strong acids or high temperatures. The syntheses of azoles using one-pot reactions are attracting increasing attention as alternatives to

Mechanochemical synthesis of unsymmetrical salens for the preparation of Co–salen complexes and their evaluation as catalysts for the synthesis of α-aryloxy alcohols via asymmetric phenolic kinetic resolution of terminal epoxides

• Shengli Zuo,
• Shuxiang Zheng,
• Jianjun Liu and
• Ang Zuo

Beilstein J. Org. Chem. 2022, 18, 1416–1423, doi:10.3762/bjoc.18.147

• ]. Inspired by the mechanochemical chemistry technology to simplify chemical processes and eliminate the use of organic solvents, salen compounds have been synthesized by the “green” grinding strategy previously [30][31][32][33][34][35][36][37][38][39]. Herein, we report a one-pot two-step mechanochemical

• The mechanochemical study examined the synthesis of several unsymmetrical salens using monoammonium salts and salicylaldehydes (Scheme 2). Agate mortar and pestle were used for the one-pot two-step mechanochemical reactions (see Supporting Information File 1). Initially, 1,2-diaminocyclohexane or

• –salen catalysts. Synthetic approach to our unsymmetrical Co–salen catalyst 2f for the asymmetric synthesis of α-aryloxy alcohols. Mechanochemical one-pot two-step synthesis of unsymmetrical salens 1a–h. Reaction conditions: salicylaldehyde (1 mmol) and diamine unilateral hydrochloride salt (2 mmol) were

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

• coupling revealed the incompatibility of the lactone function; therefore, it was reduced with DIBAL-H then transformed into 19 by a one pot acetalization–desilylation procedure (91:9 mixture of diastereomers) [17]. Hydrozirconation followed by treatment with iodine furnished the target vinyl iodide 20

Make or break: the thermodynamic equilibrium of polyphosphate kinase-catalysed reactions

• Michael Keppler,
• Sandra Moser,
• Henning J. Jessen,
• Christoph Held and
• Jennifer N. Andexer

Beilstein J. Org. Chem. 2022, 18, 1278–1288, doi:10.3762/bjoc.18.134

• an analytical scale, this reaction reached conversions of up to 94%, which agrees with the thermodynamic equilibrium for acetate kinase of at least 90%:10% ATP:ADP [26]. A comparable one-pot synthesis was recently published by the group of Li (Table 1) using two PPKs (PPK2-II and PPK2-I) with polyP

A one-pot electrochemical synthesis of 2-aminothiazoles from active methylene ketones and thioureas mediated by NH₄I

• Shang-Feng Yang,
• Pei Li,
• Zi-Lin Fang,
• Sen Liang,
• Hong-Yu Tian,
• Bao-Guo Sun,
• Kun Xu and
• Cheng-Chu Zeng

Beilstein J. Org. Chem. 2022, 18, 1249–1255, doi:10.3762/bjoc.18.130

• the in situ generation of α-iodocarbonyl ketones from constant current electrolysis (CCE) of ketones in the presence of iodide ions. It is worth noting that we have also reported an electrochemical method for the synthesis of 2-aminothiazoles via the one-pot direct α-C–H functionalization of ketones

• -alanine-assisted one-pot electrochemical synthesis of 2-aminothiazoles from active methylene ketones and thioureas mediated by NH4I (Scheme 1d). This electrochemical method features external-oxidant-free conditions and avoids the prefunctionalization of the substrates. Results and Discussion To

• dehydration to give the heterocyclic product 3. At the cathode, protons are reduced to release H2. Conclusion In conclusion, we have developed a one-pot electrochemical strategy for the synthesis of 2-amniothiazoles by the reaction of active methylene ketones with thioureas. The electrochemical synthesis was