Photocatalytic deaminative benzylation and alkylation of tetrahydroisoquinolines with N-alkylpyrydinium salts

• David Schönbauer,
• Carlo Sambiagio,
• Timothy Noël and
• Michael Schnürch

Beilstein J. Org. Chem. 2020, 16, 809–817, doi:10.3762/bjoc.16.74

• , electrophilic alkyl radicals were used in several transformations, such as electrophilic cross couplings under nickel catalysis, either with boronic acids [35] or different (aryl)halides [36][37][38]. Furthermore, visible light-promoted uncatalyzed electron transfer via the formation of electron donor–acceptor

Recent advances in Cu-catalyzed C(sp³)–Si and C(sp³)–B bond formation

• Balaram S. Takale,
• Ruchita R. Thakore,
• Elham Etemadi-Davan and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2020, 16, 691–737, doi:10.3762/bjoc.16.67

• of alkyl or aryl halides. While there are reports on the formation of C–B bonds in the presence of NHC complexes [87] with Au [88], Pd [89], Pt [90], and Ir [91] catalysts, the focus here is on Cu-catalyzed reactions. Enantioselective processes have also been studied due to applications of medicinal

Efficient synthesis of 3,6,13,16-tetrasubstituted-tetrabenzo[a,d,j,m]coronenes by selective C–H/C–O arylations of anthraquinone derivatives

• Seiya Terai,
• Yuki Sato,
• Takuya Kochi and
• Fumitoshi Kakiuchi

Beilstein J. Org. Chem. 2020, 16, 544–550, doi:10.3762/bjoc.16.51

• groups to form biaryl frameworks. Traditionally, transition-metal-catalyzed cross-coupling reactions of aryl halides or pseudohalides with arylmetal reagents have been employed for the connection of two aryl units [5][6][7][8][9]. However, in search of more efficient synthetic routes, C–H arylation

Copper-catalyzed remote C–H arylation of polycyclic aromatic hydrocarbons (PAHs)

• Anping Luo,
• Min Zhang,
• Zhangyi Fu,
• Jingbo Lan,
• Di Wu and
• Jingsong You

Beilstein J. Org. Chem. 2020, 16, 530–536, doi:10.3762/bjoc.16.49

• it possible to introduce useful functional groups into the products through the further transformation of corresponding aryl halides. 2-Naphthyliodonium salt could react smoothly with 1a to provide 3p in 66% yield (Scheme 2, 3p). Moreover, thiophen-2-yliodonium salt could be tolerated, albeit with a

Copper-promoted/copper-catalyzed trifluoromethylselenolation reactions

• Clément Ghiazza and
• Anis Tlili

Beilstein J. Org. Chem. 2020, 16, 305–316, doi:10.3762/bjoc.16.30

• the desired corresponding products were generally obtained in very good yields. The application scope of the [(bpy)CuSeCF3]2 complex was then extended to aromatic halides for the formation of C(sp2)–SeCF3 bonds. The authors demonstrated that a very broad range of (hetero)aryl halides and vinyl halides

• )–SeCF3 bonds with [(bpy)CuSeCF3]2 developed by the group of Weng. Trifluoromethylselenolation of vinyl and (hetero)aryl halides with [(bpy)CuSeCF3]2 by the group of Weng. Trifluoromethylselenolation of terminal alkynes using [(bpy)CuSeCF3]2 by the group of You and Weng. Trifluoromethylselenolation of

Starazo triple switches – synthesis of unsymmetrical 1,3,5-tris(arylazo)benzenes

• Andreas H. Heindl and
• Hermann A. Wegner

Beilstein J. Org. Chem. 2020, 16, 22–31, doi:10.3762/bjoc.16.4

• Baeyer–Mills reactions and the other based on Pd-catalyzed coupling reactions of arylhydrazides and aryl halides, followed by oxidation, were investigated. The Pd-catalyzed route efficiently led to the target compounds, unsymmetrical tris(arylazo)benzenes. These triple switches were preliminarily

• example of such compounds are 1,3,5-tris(arylazo)benzenes – ‘starazos’ – introduced by Cho and co-workers in 2004 (Figure 1) [10]. Despite their successful synthesis, using Pd-catalyzed coupling reactions of aryl halides and arylhydrazides [11] followed by Cu(I)-mediated oxidation, the photochemical

Functionalization of the imidazo[1,2-a]pyridine ring in α-phosphonoacrylates and α-phosphonopropionates via microwave-assisted Mizoroki–Heck reaction

• Damian Kusy,
• Agata Wojciechowska,
• Joanna Małolepsza and
• Katarzyna M. Błażewska

Beilstein J. Org. Chem. 2020, 16, 15–21, doi:10.3762/bjoc.16.3

• for the 6- and 7-substituted analogs 1a–c, but no product was observed in the reaction with the 8-halogeno-imidazo[1,2-a]pyridine analog 1d [25]. As the Mizoroki–Heck reaction is sensitive to the electronic properties of the aryl halides, with electron-withdrawing substituents imparting a smaller

Diversity-oriented synthesis of spirothiazolidinediones and their biological evaluation

• Sambasivarao Kotha,
• Gaddamedi Sreevani,
• Lilya U. Dzhemileva,
• Milyausha M. Yunusbaeva,
• Usein M. Dzhemilev and
• Vladimir A. D’yakonov

Beilstein J. Org. Chem. 2019, 15, 2774–2781, doi:10.3762/bjoc.15.269

• bromide (6a) in the presence of Mo(CO)6 in acetonitrile at 90 °C under microwave irradiation (MWI) conditions to give the co-trimerized spiro derivative 8a (Scheme 2). The free NH moiety of thiazolidinedione 3 was alkylated using alkyl or aryl halides in the presence of Et3N using DCM as solvent. To our

A review of asymmetric synthetic organic electrochemistry and electrocatalysis: concepts, applications, recent developments and future directions

• Munmun Ghosh,
• Valmik S. Shinde and
• Magnus Rueping

Beilstein J. Org. Chem. 2019, 15, 2710–2746, doi:10.3762/bjoc.15.264

• the major diastereomers of 151a and 153a, respectively, allowed access to optically active mandelic acid esters (Scheme 49). In 1997, Durandetti’s group published a Ni-catalyzed method for the electroreductive coupling between aryl halides and α-chloropropionic acid derivatives 153 in which the

Installation of -SO₂F groups onto primary amides

• Jing Liu,
• Shi-Meng Wang,
• Njud S. Alharbi and
• Hua-Li Qin

Beilstein J. Org. Chem. 2019, 15, 1907–1912, doi:10.3762/bjoc.15.186

• liver [23]. The nucleotide-derived probe 5’-(para-fluorosulfonylbenzoyl)adenosine (5’-FSBA) was used for labelling the second nucleotide binding site, the adenine nucleotide regulatory site [24]. In addition, aryl fluorosulfates have also been widely applied as sustainable alternative to aryl halides in

A metal-free approach for the synthesis of amides/esters with pyridinium salts of phenacyl bromides via oxidative C–C bond cleavage

• Kesari Lakshmi Manasa,
• Yellaiah Tangella,
• Namballa Hari Krishna and
• Mallika Alvala

Beilstein J. Org. Chem. 2019, 15, 1864–1871, doi:10.3762/bjoc.15.182

• [6][7], anhydrides [8], esters [9], and acyl azides [10] with amines by employing coupling reagents [11]. Alternative protocols include the Staudinger–Vilarrasa reaction [12], Schmidt reaction [13][14], Beckmann rearrangement [15], aminocarbonylation of aryl halides [16], Staudinger ligation [17

Recent advances on the transition-metal-catalyzed synthesis of imidazopyridines: an updated coverage

• Gagandeep Kour Reen,
• Ashok Kumar and
• Pratibha Sharma

Beilstein J. Org. Chem. 2019, 15, 1612–1704, doi:10.3762/bjoc.15.165

• oxidation states (Cu(0), Cu(I), Cu(II), and Cu(III)). Copper has been known for a long time to act as a catalyst for cross-coupling reactions (Ullmann–Goldberg reaction), cyanation of aryl halides (Rosenmund–von Braun reaction), Hurtley reaction and intermolecular oxidative cyclization of haloalkynes [41

• . The Pd-catalyzed Sonogashira reaction has successfully constructed arylated internal alkynes that are important intermediates in organic synthesis, molecular electronics and polymers [56]. C–N bond forming reactions between aryl halides and amines/amides/sulfonamides have been extensively studied in

Synthesis of 9-O-arylated berberines via copper-catalyzed C_Ar–O coupling reactions

• Qiaoqiao Teng,
• Xinhui Zhu,
• Qianqian Guo,
• Weihua Jiang,
• Jiang Liu and
• Qi Meng

Beilstein J. Org. Chem. 2019, 15, 1575–1580, doi:10.3762/bjoc.15.161

• structure. Considering the great abundance of aryl halides, the method allows the preparation of more diverse BBR derivatives in the future. The relevant biological study of the newly synthesized compounds is currently underway in our laboratory. Synthetic pathway of 9-O-R BBR. Resonance of berberrubine

Selenophene-containing heterotriacenes by a C–Se coupling/cyclization reaction

• Pierre-Olivier Schwartz,
• Sebastian Förtsch,
• Astrid Vogt,
• Elena Mena-Osteritz and
• Peter Bäuerle

Beilstein J. Org. Chem. 2019, 15, 1379–1393, doi:10.3762/bjoc.15.138

• , and potassium hydroxide as base in DMSO (Scheme 1). This method has been previously used for the synthesis of symmetrical diaryl selenides from aryl halides [28]. Attempts to use the corresponding 3,3’-dibromo-2,2’-bithiophene as starting material for the synthesis of either DTS 2 with the same

Multicomponent reactions (MCRs): a useful access to the synthesis of benzo-fused γ-lactams

• Edorta Martínez de Marigorta,
• Jesús M. de Los Santos,
• Ana M. Ochoa de Retana,
• Javier Vicario and
• Francisco Palacios

Beilstein J. Org. Chem. 2019, 15, 1065–1085, doi:10.3762/bjoc.15.104

• reaction of propiolic acid and aryl halides [78]. Furthermore, the authors have been able to carry out the reaction in a sequential manner starting from propiolic acid and aryl iodides in the presence of caesium carbonate and a palladium catalyst. Next, addition of 2-iodobenzoic acid and ammonium acetate

Metal-free C–H mercaptalization of benzothiazoles and benzoxazoles using 1,3-propanedithiol as thiol source

• Yan Xiao,
• Bing Jing,
• Xiaoxia Liu,
• Hongyu Xue and
• Yajun Liu

Beilstein J. Org. Chem. 2019, 15, 279–284, doi:10.3762/bjoc.15.24

• reaction conditions were obtained as follows: benzothiazole (1.0 mmol), 1,3-propanedithiol (2.0 equiv), KOH (5.0 equiv), DMSO (3 mL), 130 °C, 12 h. We further investigated several common thiol surrogates, which are often used in the C–H mercaptalization of aryl halides. Under the optimized conditions, 1

Learning from B₁₂ enzymes: biomimetic and bioinspired catalysts for eco-friendly organic synthesis

• Keishiro Tahara,
• Ling Pan,
• Toshikazu Ono and
• Yoshio Hisaeda

Beilstein J. Org. Chem. 2018, 14, 2553–2567, doi:10.3762/bjoc.14.232

• using various electrophiles such as alkyl halides [13], vinyl halides [14][15][16], aryl halides [17][18] and epoxides [19][20] in homogeneous solutions (Figure 1b). 1-2. Design of biomimetic and bioinspired B12 catalytic systems Schematic representations of B12 enzymes and enzyme-involving systems are

Synthesis of aryl sulfides via radical–radical cross coupling of electron-rich arenes using visible light photoredox catalysis

• Amrita Das,
• Mitasree Maity,
• Simon Malcherek,
• Burkhard König and
• Julia Rehbein

Beilstein J. Org. Chem. 2018, 14, 2520–2528, doi:10.3762/bjoc.14.228

• prefunctionalized sulfenylating reagents. Recently Lei and co-workers reported a DDQ-mediated selective radical–radical cross coupling between electron-rich arenes and thiols [40]. Miyake et al. reported the visible light-promoted cross-coupling reaction between aryl halides and arylthiols via an intermolecular

Synergistic approach to polycycles through Suzuki–Miyaura cross coupling and metathesis as key steps

• Sambasivarao Kotha,
• Milind Meshram and
• Chandravathi Chakkapalli

Beilstein J. Org. Chem. 2018, 14, 2468–2481, doi:10.3762/bjoc.14.223

• DDQ to give biaryl products 99a,b. Further, aryl halides 99a,b were subjected to SM coupling by employing various boronic acids (e.g., 4-formylphenylboronic acid (100) to produce biaryl derivative 101 (80% from 99a and 74% from 99b). Very recently, Suresh Babu and co-workers [47] demonstrated a new

Cobalt- and rhodium-catalyzed carboxylation using carbon dioxide as the C1 source

• Tetsuaki Fujihara and
• Yasushi Tsuji

Beilstein J. Org. Chem. 2018, 14, 2435–2460, doi:10.3762/bjoc.14.221

• carboxylation of aryl halides and pseudohalides using CO2 is an important reaction to yield benzoic acid derivatives. In 2009, Martin reported the Pd-catalyzed carboxylation of aryl bromides using ZnEt2 as the reductant [31]. In 2012, we first reported the Ni-catalyzed carboxylation of aryl chlorides and vinyl

• . found the direct carboxylation reaction with CO2 under photo-irradiation reaction conditions [46]. Jamison et al. also reported the synthesis of α-amino acid derivatives using amine and CO2 [47]. Iwasawa disclosed the Pd-catalyzed carboxylation of aryl halides using CO2 in the presence of an Ir photo

Synthesis of indolo[1,2-c]quinazolines from 2-alkynylaniline derivatives through Pd-catalyzed indole formation/cyclization with N,N-dimethylformamide dimethyl acetal

• Antonio Arcadi,
• Sandro Cacchi,
• Giancarlo Fabrizi,
• Francesca Ghirga,
• Antonella Goggiamani,
• Antonia Iazzetti and
• Fabio Marinelli

Beilstein J. Org. Chem. 2018, 14, 2411–2417, doi:10.3762/bjoc.14.218

• -catalyzed reaction of o-(o-aminophenylethynyl) trifluoroacetanilides 5 with aryl halides and aryldiazonium salts led to the formation of 12-arylindolo[1,2-c]quinazolin-6(5H)-ones 8 in moderate to excellent yields (Scheme 2a) [23]. Very likely, under these reaction conditions, the palladium-catalyzed

• )anilines 15 (see below). Results and Discussion We have previously reported that arylboronic acids 12 can be used in place of aryl halides in the Pd-catalyzed synthesis of indoles through aminopalladation/reductive elimination reaction from 2-alkynyltrifluoroacetanilides [24]. This reaction is carried out

D-Fructose-based spiro-fused PHOX ligands: synthesis and application in enantioselective allylic alkylation

• Michael R. Imrich,
• Jochen Kraft,
• Cäcilia Maichle-Mössmer and
• Thomas Ziegler

Beilstein J. Org. Chem. 2018, 14, 2082–2089, doi:10.3762/bjoc.14.182

• nitrile is slower compared to the unstabilized 9b. The Stoltz and co-workers reported the preparation of a series of PHOX ligands using Buchwald’s copper-catalyzed C–P bond construction [48][49]. This reaction allows the Ullmann coupling of aryl halides with secondary phosphines to afford tertiary

Applications of organocatalysed visible-light photoredox reactions for medicinal chemistry

• Michael K. Bogdos,
• Emmanuel Pinard and
• John A. Murphy

Beilstein J. Org. Chem. 2018, 14, 2035–2064, doi:10.3762/bjoc.14.179

• reduction of aryl halides to the corresponding non-halogenated aromatics. This was extended to the coupling of aryl halides to a variety of substituted pyrroles, using N,N-bis(2,6-diisopropylphenyl)perylene-3,4,9,10-bis(dicarboximide) (PDI) as the photocatalyst, under blue LED irradiation, in DMSO and in

Synthesis of 9-arylalkynyl- and 9-aryl-substituted benzo[b]quinolizinium derivatives by Palladium-mediated cross-coupling reactions

• Siva Sankar Murthy Bandaru,
• Darinka Dzubiel,
• Heiko Ihmels,
• Mohebodin Karbasiyoun,
• Mohamed M. A. Mahmoud and
• Carola Schulzke

Beilstein J. Org. Chem. 2018, 14, 1871–1884, doi:10.3762/bjoc.14.161

• for subsequent synthesis, as it has been reported that organotrifluoroborates may also be employed as starting materials in Suzuki–Miyaura coupling reactions of aryl halides [52][53]. Indeed, starting from benzo[b]quinolizinium-9-trifluoroborate (3b) and the corresponding aryldiazonium ions the 9

Water-soluble SNS cationic palladium(II) complexes and their Suzuki–Miyaura cross-coupling reactions in aqueous medium

• Alphonse Fiebor,
• Richard Tia,
• Banothile C. E. Makhubela and
• Henok H. Kinfe

Beilstein J. Org. Chem. 2018, 14, 1859–1870, doi:10.3762/bjoc.14.160

• coupling reaction is a powerful method for the synthesis of ubiquitous biaryls and has been extensively employed in the synthesis of natural products, pharmaceuticals, agrochemicals, and polymers. The reaction usually involves a palladium-catalysed coupling of aryl boronates with aryl halides in organic