Asymmetric organocatalyzed synthesis of coumarin derivatives

• Natália M. Moreira,
• Lorena S. R. Martelli and
• Arlene G. Corrêa

Beilstein J. Org. Chem. 2021, 17, 1952–1980, doi:10.3762/bjoc.17.128

• -catalyzed cross-coupling reactions of coumarin derivatives [24]. Coumarins are a promising scaffold for design and development of bioactive agents, however it possesses a flat system [25]. One of the attractive benefits of introducing chirality in a drug candidate is that it leads to increased complexity to

On the application of 3d metals for C–H activation toward bioactive compounds: The key step for the synthesis of silver bullets

• Renato L. Carvalho,
• Amanda S. de Miranda,
• Mateus P. Nunes,
• Roberto S. Gomes,
• Guilherme A. M. Jardim and
• Eufrânio N. da Silva Júnior

Beilstein J. Org. Chem. 2021, 17, 1849–1938, doi:10.3762/bjoc.17.126

Sustainable manganese catalysis for late-stage C–H functionalization of bioactive structural motifs

• Jongwoo Son

Beilstein J. Org. Chem. 2021, 17, 1733–1751, doi:10.3762/bjoc.17.122

• selectivity, which is observed at the more electron-rich and the less sterically hindered position. Manganese-catalyzed late-stage C–H alkynylation Alkynes are invaluable intermediates in organic synthesis and are conventionally prepared via palladium-catalyzed cross-coupling reactions [62]. Moreover, they

Methodologies for the synthesis of quaternary carbon centers via hydroalkylation of unactivated olefins: twenty years of advances

• Thiago S. Silva and
• Fernando Coelho

Beilstein J. Org. Chem. 2021, 17, 1565–1590, doi:10.3762/bjoc.17.112

• ]. Nickel catalysis is a viable alternative for this kind of cross-coupling reactions due to its particular radical mechanism, instead of the common metal-oxidative addition to organohalides [102][103][104]. Examples of the coupling between primary, secondary, and even tertiary alkyl halides with

• stability of some of them [105][106]. The combination of Ni complexes with silyl reductants could avoid these issues by transforming the olefins in the nucleophile partners in cross-coupling reactions under mild conditions [107]. In 2018, the Fu group developed an enantioconvergent cross-coupling between

Substituted nitrogen-bridged diazocines

• Pascal Lentes,
• Jeremy Rudtke,
• Thomas Griebenow and
• Rainer Herges

Beilstein J. Org. Chem. 2021, 17, 1503–1508, doi:10.3762/bjoc.17.107

• makes them promising candidates for applications in photopharmacology. The halogen substituents allow further functionalization via cross-coupling reactions. Keywords: bridged azobenzene; diazocine; photopharmacology; photoswitch; triazocine; visible light switch; water-soluble switch; Introduction

Organocatalytic asymmetric Michael/acyl transfer reaction between α-nitroketones and 4-arylidenepyrrolidine-2,3-diones

• Chandrakanta Parida and
• Subhas Chandra Pan

Beilstein J. Org. Chem. 2021, 17, 1447–1452, doi:10.3762/bjoc.17.100

• ) derivatives (Table 3, entries 3–5). These products could be particularly useful for further transformations via cross-coupling reactions. The ortho-fluoroarylidene-substituted pyrrolidine-2,3-dione 1g also participated in the reaction to deliver product 3t in 86% ee (Table 3, entry 6). 2,4-Disubstitution at

Manganese/bipyridine-catalyzed non-directed C(sp³)–H bromination using NBS and TMSN₃

• Kumar Sneh,
• Takeru Torigoe and
• Yoichiro Kuninobu

Beilstein J. Org. Chem. 2021, 17, 885–890, doi:10.3762/bjoc.17.74

• variety of functionalities, such as boron-, silicon-, nitrogen-, and oxygen-based functional groups, and in C−C bond forming reactions, such as cross-coupling reactions [1][2][3][4][5][6]. The traditional method used for the preparation of alkyl bromides is the reaction of their corresponding alkyl

Highly regio- and stereoselective phosphinylphosphination of terminal alkynes with tetraphenyldiphosphine monoxide under radical conditions

• Dat Phuc Tran,
• Yuki Sato,
• Yuki Yamamoto,
• Shin-ichi Kawaguchi,
• Shintaro Kodama,
• Akihiro Nomoto and
• Akiya Ogawa

Beilstein J. Org. Chem. 2021, 17, 866–872, doi:10.3762/bjoc.17.72

• as 1,2-bis(diphenylphosphino)ethane (Ph2PCH2CH2PPh2, dppe) are employed as bidentate ligands and are effective in controlling important catalytic reactions such as cross-coupling reactions [9][10][11][12][13][14][15][16][17][18]. 1,2-Bis(diphenylphosphino)ethylene (Ph2PCH=CHPPh2, dppen) is among

A chromatography-free and aqueous waste-free process for thioamide preparation with Lawesson’s reagent

• Ke Wu,
• Yichen Ling,
• An Ding,
• Liqun Jin,
• Nan Sun,
• Baoxiang Hu,
• Zhenlu Shen and
• Xinquan Hu

Beilstein J. Org. Chem. 2021, 17, 805–812, doi:10.3762/bjoc.17.69

• -coupling reactions [28][29][30][31][32][33][34][35]. The thio-substitution of amides with LR is an efficient and straightforward method, because the amide substrates and LR are readily available and the reactions are easily operated [8][9][36][37][38][39][40]. With thio-substitution of amides as a model

• incomparable chelating ability towards selected transition metals, and the corresponding complexes were applied in various areas such as chemical-sensor materials, tunable redox-potential complexes, polymer hybrid luminescence materials, building blocks for multinuclear complexes, and as catalysts for cross

The preparation and properties of 1,1-difluorocyclopropane derivatives

• Kymbat S. Adekenova,
• Peter B. Wyatt and
• Sergazy M. Adekenov

Beilstein J. Org. Chem. 2021, 17, 245–272, doi:10.3762/bjoc.17.25

Selective synthesis of α-organylthio esters and α-organylthio ketones from β-keto esters and sodium S-organyl sulfurothioates under basic conditions

• Jean C. Kazmierczak,
• Roberta Cargnelutti,
• Thiago Barcellos,
• Claudio C. Silveira and
• Ricardo F. Schumacher

Beilstein J. Org. Chem. 2021, 17, 234–244, doi:10.3762/bjoc.17.24

• -rich N-heterocycles [2][3][4], decarboxylative cross-coupling reactions with propiolic acid derivatives [5], Michael addition reaction [6], cross-couplings catalyzed by Pd [7] and Cu salts [8][9], the preparation of symmetrical and nonsymmetrical disulfides [10][11], and the synthesis of β-acetamido

Progress in the total synthesis of inthomycins

• Bidyut Kumar Senapati

Beilstein J. Org. Chem. 2021, 17, 58–82, doi:10.3762/bjoc.17.7

• functional groups and isomerizable double bonds in the conjugated triene moiety. Various stereoselective cross-coupling reactions such as Stille, Suzuki, or Sonogashira or Suzuki–Miyaura have been utilized to construct the geometrically distinctive polyene systems of inthomycins A–C (1–3). The elegant work

Metal-free synthesis of biarenes via photoextrusion in di(tri)aryl phosphates

• Hisham Qrareya,
• Lorenzo Meazza,
• Stefano Protti and
• Maurizio Fagnoni

Beilstein J. Org. Chem. 2020, 16, 3008–3014, doi:10.3762/bjoc.16.250

• challenge [11][12][13]. Common methods, such as the Ullmann and Gomberg synthesis [14][15][16] have been nowadays supplanted by the much more versatile metal-catalyzed cross-coupling reactions [17][18][19][20][21][22][23]. This excellent approach still encounters some limitation in the scope and in the

• results and of the reported literature [58][61], to the singlet monomeric excited state and to the exciplex, respectively. While aryl phosphates have been only sparsely used as substrates in thermal cross-coupling reactions [65][66][67], their photochemical behavior has been the subject of various

Palladium nanoparticles supported on chitin-based nanomaterials as heterogeneous catalysts for the Heck coupling reaction

• Tony Jin,
• Malickah Hicks,
• Davis Kurdyla,
• Sabahudin Hrapovic,
• Edmond Lam and
• Audrey Moores

Beilstein J. Org. Chem. 2020, 16, 2477–2483, doi:10.3762/bjoc.16.201

• benign conditions, outcompeting the use of other catalysts supported on biomass-based nanomaterials, including cellulose nanocrystals. These initial results show the potential for using chitinous nanomaterials as effective catalyst supports in cross-coupling reactions. Keywords: chitin; chitosan; Heck

Chan–Evans–Lam N1-(het)arylation and N1-alkеnylation of 4-fluoroalkylpyrimidin-2(1H)-ones

• Viktor M. Tkachuk,
• Oleh O. Lukianov,
• Mykhailo V. Vovk,
• Isabelle Gillaizeau and
• Volodymyr A. Sukach

Beilstein J. Org. Chem. 2020, 16, 2304–2313, doi:10.3762/bjoc.16.191

• uniquely advantageous means to perform C–N cross-coupling reactions [15][16][17]. The corresponding Ullmann-type reaction currently known as Chan–Evans–Lam (CEL) coupling is characterized by the combination of two nucleophilic reactants which implies that oxidative processes with atmospheric oxygen play a

Synergy between supported ionic liquid-like phases and immobilized palladium N-heterocyclic carbene–phosphine complexes for the Negishi reaction under flow conditions

• Edgar Peris,
• Raúl Porcar,
• María Macia,
• Jesús Alcázar,
• Eduardo García-Verdugo and
• Santiago V. Luis

Beilstein J. Org. Chem. 2020, 16, 1924–1935, doi:10.3762/bjoc.16.159

• modulated through systematic variations of the steric and electronic design vectors of the NHC ligand [2]. These complexes have been used as highly efficient catalysts for a wide variety of C–C and C–X cross-coupling reactions [3]. Among others, different NHC–Pd complexes have been designed as efficient

• pursuit of NHC immobilized metal complexes many different materials of organic and inorganic nature have been used as supports [5]. Several reports describe the synthesis of supported palladium–NHC complexes (Pd–NHC) and their application in cross-coupling reactions [8][9][10]. The main flaw of this type

Regiodivergent synthesis of functionalized pyrimidines and imidazoles through phenacyl azides in deep eutectic solvents

• Paola Vitale,
• Luciana Cicco,
• Ilaria Cellamare,
• Filippo M. Perna,
• Antonio Salomone and
• Vito Capriati

Beilstein J. Org. Chem. 2020, 16, 1915–1923, doi:10.3762/bjoc.16.158

• ], (c) carbon–sulfur bond-forming reactions [9], (d) directed ortho-metalation and nucleophilic acyl substitution strategies [10], (e) Pd-catalyzed aminocarbonylation of aryl iodides, Suzuki–Miyaura and Sonogashira cross-coupling reactions [11][12][13], (f) Cu-catalyzed C–N coupling reactions [14], and

• cross-coupling reactions. A 4-fluoro-substituted phenacyl chloride as well as a bromomethyl 2-naphthyl ketone proved to be competent substrates as well, thus furnishing the corresponding imidazoles 3i/3i' and 3j in 67–87% yield. Conversely, a phenacyl halide decorated with an additional phenyl group at

When metal-catalyzed C–H functionalization meets visible-light photocatalysis

• Lucas Guillemard and
• Joanna Wencel-Delord

Beilstein J. Org. Chem. 2020, 16, 1754–1804, doi:10.3762/bjoc.16.147

Tuneable access to indole, indolone, and cinnoline derivatives from a common 1,4-diketone Michael acceptor

• Dalel El-Marrouki,
• Sabrina Touchet,
• Abderrahmen Abdelli,
• Hédi M’Rabet,
• Mohamed Lotfi Efrit and
• Philippe C. Gros

Beilstein J. Org. Chem. 2020, 16, 1722–1731, doi:10.3762/bjoc.16.144

• ][38][39] or triketones [10][13] and enaminones [40][41][42][43] as starting materials. For the synthesis of cinnoline derivatives, aryldiazenes and aryltriazenes are substrates of choice for transition-metal-catalyzed (Rh, Pd, Cu) cross-coupling reactions, followed by intramolecular cyclizations [44

Disposable cartridge concept for the on-demand synthesis of turbo Grignards, Knochel–Hauser amides, and magnesium alkoxides

• Mateo Berton,
• Kevin Sheehan,
• Andrea Adamo and
• D. Tyler McQuade

Beilstein J. Org. Chem. 2020, 16, 1343–1356, doi:10.3762/bjoc.16.115

• of the corresponding Grignard intermediate in the presence of ZnCl2 and LiCl, which were subsequently used in Negishi cross-coupling reactions [41]. The most recent example, by the Löb group, reported a pilot plant reactor including a Mg replenish unit that allowed to generate phenylmagnesium bromide

Highly selective Diels–Alder and Heck arylation reactions in a divergent synthesis of isoindolo- and pyrrolo-fused polycyclic indoles from 2-formylpyrrole

• Carlos H. Escalante,
• Eder I. Martínez-Mora,
• Carlos Espinoza-Hicks,
• Alejandro A. Camacho-Dávila,
• Fernando R. Ramos-Morales,
• Francisco Delgado and
• Joaquín Tamariz

Beilstein J. Org. Chem. 2020, 16, 1320–1334, doi:10.3762/bjoc.16.113

• similar chemoselectivity has been previously observed, being explained as a consequence of the acidity of the C–H bond being cleaved [6][44]. Additional intramolecular cross-coupling reactions were carried out by utilizing dimethyl malonates 8k and 8l, which were prepared through the N-benzylation of 16c

• approach to the fused aza-heterocyclic pentacycle 12. Preparation of 1,2-substituted pyrroles 8a–h.a Diels–Alder reactions of 2-vinylpyrroles 8a–j and 16a,b with maleimides 7b,c.a Heck cross-coupling reactions of 9g–j and 9m for the preparation of pentacycles 11a–e.a Synthesis of tetrahydropyrrolo[3,4-e

Palladium-catalyzed regio- and stereoselective synthesis of aryl and 3-indolyl-substituted 4-methylene-3,4-dihydroisoquinolin-1(2H)-ones

• Valeria Nori,
• Antonio Arcadi,
• Armando Carlone,
• Fabio Marinelli and
• Marco Chiarini

Beilstein J. Org. Chem. 2020, 16, 1084–1091, doi:10.3762/bjoc.16.95

• stereoselective Pd-catalyzed cascade reactions, consisting of the addition of in situ-generated arylpalladium complexes over a proximate carbon–carbon triple bond, followed by cross-coupling reactions, have been reported [26][27][28][29][30][31]. Our continuing interest in the palladium-catalyzed reactions of

Fluorinated phenylalanines: synthesis and pharmaceutical applications

• Laila F. Awad and
• Mohammed Salah Ayoup

Beilstein J. Org. Chem. 2020, 16, 1022–1050, doi:10.3762/bjoc.16.91

• reported herein different methods for their synthesis. 1.1. Negishi cross coupling of aryl halide and organozinc compounds Jackson and co-workers reported the synthesis of a range of phenylalanine derivatives via Negishi cross-coupling reactions of aryl halides and Zn homoenolates of the protected (R

• targeted compounds 88a,b (Scheme 20). Cross-coupling reactions with boronic acids were found to be successful only for the synthesis of para and meta-derivatives. Several attempts were made to prepare the ortho-substituted derivatives 93 and 95. The synthesis of ᴅ,ʟ-93 or ʟ-95 was achieved by vinylation of

Aryl-substituted acridanes as hosts for TADF-based OLEDs

• Naveen Masimukku,
• Dalius Gudeika,
• Oleksandr Bezvikonnyi,
• Ihor Syvorotka,
• Rasa Keruckiene,
• Dmytro Volyniuk and
• Juozas V. Grazulevicius

Beilstein J. Org. Chem. 2020, 16, 989–1000, doi:10.3762/bjoc.16.88

• according to the reported procedure [28]. The subsequent alkylation of 1 using bromoethane afforded the N-ethylated dibromo compound 2 in 80% yield. The target compounds 3–6 were then obtained by Suzuki cross-coupling reactions between brominated acridan 2 and the respective phenylboronic acids in the

Accelerating fragment-based library generation by coupling high-performance photoreactors with benchtop analysis

• Quentin Lefebvre,
• Christophe Salomé and
• Thomas C. Fessard

Beilstein J. Org. Chem. 2020, 16, 982–988, doi:10.3762/bjoc.16.87

• collections. These are of high value to medicinal chemists to provide defined exit vectors and facilitate rational lead evolution [2][3][4][5][6][7]. Thus, we were interested in developing reliable synthetic methods and technologies to apply metal-catalyzed cross-coupling reactions to such scaffolds, which

• -catalyzed cross-coupling reactions [9]. Recently, milder cross-coupling methods using more abundant and affordable metals such as nickel, in combination with photochemistry or electrochemistry, significantly improved accessibility to N-arylated complex amines [10][11][12]. Results and Discussion As we

• reactions, and ranged from 6% to 50% for copper-catalyzed cross-coupling reactions [13]. Much information could be obtained from this screening. Electron-deficient aryl bromides led to better yields than neutral and electron-rich partners, as observed in previous reports on photochemically- or