Palladium-catalyzed three-component radical-polar crossover carboamination of 1,3-dienes or allenes with diazo esters and amines

• Geng-Xin Liu,
• Xiao-Ting Jie,
• Ge-Jun Niu,
• Li-Sheng Yang,
• Xing-Lin Li,
• Jian Luo and
• Wen-Hao Hu

Beilstein J. Org. Chem. 2024, 20, 661–671, doi:10.3762/bjoc.20.59

• electrophilic trapping of onium ylides generated from metal carbenes with nucleophiles, providing an ingenious difunctionalization strategy for diazo compounds to access structurally complex and diverse molecules (Scheme 1b, top) [28][29]. In recent years, radical-mediated MCRs with diazo compounds have become

• reaction of diazo compounds mediated by visible light has been reported by the group of Gevorgyan, which achieves the monofunctionalization of alkenes [52]. Inspired by these collective studies, we considered diazo compounds could be a competent activated alkyl halide equivalent to overcome the synthetic

• limitation of the photoinduced palladium-catalyzed carboamination reactions and the radical-mediated difunctionalization of alkenes with diazo compounds. We envisioned an interesting MCR strategy with mild conditions to access unsaturated γ- and ε-AA derivatives via a π-allyl Pd radical-polar crossover

Entry to new spiroheterocycles via tandem Rh(II)-catalyzed O–H insertion/base-promoted cyclization involving diazoarylidene succinimides

• Alexander Yanovich,
• Anastasia Vepreva,
• Ksenia Malkova,
• Grigory Kantin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2024, 20, 561–569, doi:10.3762/bjoc.20.48

• towards spirocyclic scaffolds as a goal of great value [6][7][8][9]. A rich synthetic platform for the design of various types of spiroheterocycles is provided by cyclic diazo compounds [10]. Recently, we and others have demonstrated the efficient use of diazoarylidene succinimides (DAS, 1) in the

Synthesis of 2,2-difluoro-1,3-diketone and 2,2-difluoro-1,3-ketoester derivatives using fluorine gas

• Alexander S. Hampton,
• David R. W. Hodgson,
• Graham McDougald,
• Linhua Wang and
• Graham Sandford

Beilstein J. Org. Chem. 2024, 20, 460–469, doi:10.3762/bjoc.20.41

• of diazo compounds using F2 [37] is the only report of a useful synthetic procedure to selectively prepare a difluoromethylene containing product using F2 but, in these cases, CFCs, now banned under the Montreal protocol, were used as the reaction medium. Here, we demonstrate that the addition of

Copper-catalyzed multicomponent reaction of β-trifluoromethyl β-diazo esters enabling the synthesis of β-trifluoromethyl N,N-diacyl-β-amino esters

• Youlong Du,
• Haibo Mei,
• Ata Makarem,
• Ramin Javahershenas,
• Vadim A. Soloshonok and
• Jianlin Han

Beilstein J. Org. Chem. 2024, 20, 212–219, doi:10.3762/bjoc.20.21

• challenging. On the other hand, several interesting transformations of nitrile ylides from diazo compounds have been developed in the past years [31][32][33][34][35][36][37][38]. In particular, acylglycine esters could be easily constructed with ester-containing diazo compounds as the starting materials. For

• esters, which enriches the studied content of fluoroalkyl diazo compounds. Results and Discussion Due to the instability of β-carbonyl diazo compounds and the occurrence of possible side reactions [58][59][60][61], screening of reaction conditions to optimize this conversion and inhibit the occurrence of

• . Stirring was continued at room temperature for 2.5 h and the solvent was removed in vacuum. Products 4 were purified on a TLC plate of 20 cm × 20 cm using petroleum ether/ethyl acetate 7:1 (v/v) as eluent. Mumm-type rearrangement of diazo compounds. Substrate scope study of this Cu-catalyzed reaction

Identification of the p-coumaric acid biosynthetic gene cluster in Kutzneria albida: insights into the diazotization-dependent deamination pathway

• Seiji Kawai,
• Akito Yamada,
• Yohei Katsuyama and
• Yasuo Ohnishi

Beilstein J. Org. Chem. 2024, 20, 1–11, doi:10.3762/bjoc.20.1

• diazotization catalyzed by CmaA6 was much higher than that of AvaA6; almost 100% of 3-ACA and 3-AAA were converted to corresponding aromatic diazo compounds 4 and 8, respectively (Figure 3C). Kinetic analysis of AvaA7 catalyzing denitrification of 3-DAA The high conversion efficiency of 3-AAA (7) to 3-DAA (8

N-Boc-α-diazo glutarimide as efficient reagent for assembling N-heterocycle-glutarimide diads via Rh(II)-catalyzed N–H insertion reaction

• Grigory Kantin,
• Pavel Golubev,
• Alexander Sapegin,
• Alexander Bunev and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2023, 19, 1841–1848, doi:10.3762/bjoc.19.136

• acknowledged to be effective in introducing substituents to the nitrogen atoms of NH-heterocycles by means of carbene insertion into the N–H bond upon catalytic or photolytic decomposition of diazo compounds [25]. Furthermore, the reaction of N-heterocycles containing multiple non-equivalent nitrogen atoms

N-Sulfenylsuccinimide/phthalimide: an alternative sulfenylating reagent in organic transformations

• Fatemeh Doraghi,
• Seyedeh Pegah Aledavoud,
• Mehdi Ghanbarlou,
• Bagher Larijani and
• Mohammad Mahdavi

Beilstein J. Org. Chem. 2023, 19, 1471–1502, doi:10.3762/bjoc.19.106

• traditional heating methods. In the meanwhile, Qiu and Xu et al. reported the coupling reaction between diazo compounds 163 and N-sulfenylsuccinimides 1 under catalyst-, base-, and additive-free conditions (Scheme 71) [101]. The reaction proceeded via a radical pathway, in which a free carbene was generated

• HCl-promoted 1,2-thiofunctionalization of aromatic alkenes. Coupling reaction of diazo compounds with N-sulfenylsuccinimides. Multicomponent reactions of disulfides with isocyanides and other nucleophiles. α-Sulfenylation and β-sulfenylation of α,β-unsaturated carbonyl compounds.

First synthesis of acylated nitrocyclopropanes

• Kento Iwai,
• Rikiya Kamidate,
• Khimiya Wada,
• Haruyasu Asahara and
• Nagatoshi Nishiwaki

Beilstein J. Org. Chem. 2023, 19, 892–900, doi:10.3762/bjoc.19.67

• ). These structural features enable the construction of a five-membered ring upon treatment with alkenes [9], diazo compounds (reaction g) [10], and nitriles [11]. Several approaches are available for the synthesis of cyclopropanedicarboxylates 1a, which consist of three steps: 1) conjugate addition, 2

Access to cyclopropanes with geminal trifluoromethyl and difluoromethylphosphonate groups

• Ita Hajdin,
• Romana Pajkert,
• Mira Keßler,
• Jianlin Han,
• Haibo Mei and
• Gerd-Volker Röschenthaler

Beilstein J. Org. Chem. 2023, 19, 541–549, doi:10.3762/bjoc.19.39

• good to very good yields. Keywords: alkenes; cyclopropanation; diazo compounds; difluoromethylphosphonate; DFT calculations; Introduction Cyclopropanes constitute a fascinating class of organic compounds due to their unique structure and bond properties [1]. However, their synthetic utility is

• fluorinated diazo compounds might be rationalized by their low accessibility and high volatility [44]. As a part of our continuing investigations in fluorinated carbene chemistry [45][46][47][48][49], we hypothesized that the synthesis of cyclopropanes with geminal trifluoromethyl and

Practical synthesis of isocoumarins via Rh(III)-catalyzed C–H activation/annulation cascade

• Qian-Ci Gao,
• Yi-Fei Li,
• Jun Xuan and
• Xiao-Qiang Hu

Beilstein J. Org. Chem. 2023, 19, 100–106, doi:10.3762/bjoc.19.10

• ]. Compared with highly sensitive diazo compounds, iodonium ylides are known to show ready availability and good stability [29][30]. Our group has recently demonstrated that iodonium ylides can be used as carbene precursors in the Rh-catalyzed [4 + 2] cyclization of pyrazolidinones [31]. During the

A facile approach to spiro[dihydrofuran-2,3'-oxindoles] via formal [4 + 1] annulation reaction of fused 1H-pyrrole-2,3-diones with diazooxindoles

• Pavel A. Topanov,
• Anna A. Maslivets,
• Maksim V. Dmitriev,
• Irina V. Mashevskaya,
• Yurii V. Shklyaev and
• Andrey N. Maslivets

Beilstein J. Org. Chem. 2022, 18, 1532–1538, doi:10.3762/bjoc.18.162

• room temperature, therefore, these conditions were taken as a standard for further reactions. Next, the reagent scope of the reaction was explored by involving diazooxindoles 2a–d into the reaction with FPD 1a (Table 2). Compared to substrate 2a, the presence of substituents in diazo compounds 2b–d led

• . Benzoxazine, quinoxaline, and morpholine FPDs were successfully involved into the reaction, with the modification of diazo compounds decreasing the reaction yield. The reaction time of the cycloaddition was found to be independent on substituents in the aroyl moiety of FPDs 1. The described reaction is the

• first example of a catalyst-free formal [4 + 1] cycloaddition reaction of enones and complex diazo compounds. The synthesized compounds 3 have a pharmaceutically interesting fungal metabolites-like structure with a spiro[dihydrofuran-2,3'-oxindole] moiety. Selected examples of biologically active

Facile and diastereoselective arylation of the privileged 1,4-dihydroisoquinolin-3(2H)-one scaffold

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

Beilstein J. Org. Chem. 2022, 18, 1070–1078, doi:10.3762/bjoc.18.109

• cytotoxic agents. Keywords: 1,4-dihydroisoquinol-3-one; heterocyclic diazo compounds; hydroarylation; Regitz diazo transfer; triflic acid; Introduction Besides being derivatives of (or a precursor to) the 1,2,3,4-tetrahydroisoquinoline core which itself bears a special significance from the standpoint of

• (Danheiser method [22]) or ethoxalylation [23]. Fortunately, all of the substrates 11a–s were converted cleanly and smoothly over 2–5 days into their diazo derivatives 10a–s using p-(acetamido)benzenesulfonyl azide (p-ABSA) as the diazo group donor [24] and DBU as the base. The yields of diazo compounds 10

• spectrum), mass spectrometry and, in the case of compound 10c, by single-crystal X-ray crystallography (Scheme 2). Using compound 10a as the model substrate, we proceeded to screen for suitable reaction conditions that would allow involving this kind of diazo compounds in the TfOH-promoted benzene C

Synthesis of new pyrazolo[1,2,3]triazines by cyclative cleavage of pyrazolyltriazenes

• Nicolai Wippert,
• Martin Nieger,
• Claudine Herlan,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2021, 17, 2773–2780, doi:10.3762/bjoc.17.187

• of the intermediate diazo compounds under acidic conditions [22] (Scheme 1). The structurally related 3,7-dihydro-4H-pyrazolo[3,4-d][1,2,3]triazin-4-ones 3 (Figure 1) which are substituted in position N-7 can be obtained in the same manner as described in Scheme 1, if the substitution position R1 in

α-Ketol and α-iminol rearrangements in synthetic organic and biosynthetic reactions

• Scott Benz and
• Andrew S. Murkin

Beilstein J. Org. Chem. 2021, 17, 2570–2584, doi:10.3762/bjoc.17.172

• biologically. Prekinamycin (76) and isoprekinamycin (77) are diazo compounds isolated from Streptomyces murayamensis that differ in their ring system, with the former containing a fused 6-6-5-6 skeleton and the latter containing a 6-5-6-6 skeleton. Due to their similarity and common source, it had been

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

Synthesis of β-triazolylenones via metal-free desulfonylative alkylation of N-tosyl-1,2,3-triazoles

• Soumyaranjan Pati,
• Renata G. Almeida,
• Eufrânio N. da Silva Júnior and
• Irishi N. N. Namboothiri

Beilstein J. Org. Chem. 2021, 17, 762–770, doi:10.3762/bjoc.17.66

• , these diazo compounds undergo [3 + 2] cycloadditions with suitable substrates to render various nitrogen-rich heterocycles [39]. In addition to their synthetic importance, these are frequently encountered as ligands in many metal complexes [40][41][42][43]. Our group have also employed 1,3-dicarbonyl

[2 + 1] Cycloaddition reactions of fullerene C₆₀ based on diazo compounds

• Yuliya N. Biglova

Beilstein J. Org. Chem. 2021, 17, 630–670, doi:10.3762/bjoc.17.55

• promising. They are synthesized in two main reactions: nucleophilic cyclopropanation according to the Bingel method and thermal addition of diazo compounds. This present review summarizes the material on the synthesis of monofunctionalized methanofullerenes – analogues of [60]PCBM – based on various diazo

• ]PCBM; diazo compounds; mechanisms and optimal conditions of cyclopropanation; methanofullerenes C60; Introduction Taking into consideration that all life on Earth is of organic origin. with carbon as its basic element (20% by weight of every living organism, and the fourth most abundant element in the

• discuss the primary functionalization of the fullerene core with diazo compounds to synthesize solely monosubstituted carbochain products, covers the main achievements of organic chemistry over the past 20 years in the field of [2 + 1] cycloadditions to fullerene. Review [2 + 1] Cycloaddition to C60 to

Regioselective synthesis of heterocyclic N-sulfonyl amidines from heteroaromatic thioamides and sulfonyl azides

• Vladimir Ilkin,
• Vera Berseneva,
• Tetyana Beryozkina,
• Tatiana Glukhareva,
• Lidia Dianova,
• Wim Dehaen,
• Eugenia Seliverstova and
• Vasiliy Bakulev

Beilstein J. Org. Chem. 2020, 16, 2937–2947, doi:10.3762/bjoc.16.243

• reactions of 2-diazomalonates with aliphatic amines [40][52]. The first approach leads to a mixture of two regioisomers and the second method involves the use of explosive diazo compounds. Therefore, such compounds are better prepared by a recently found method in our laboratory which includes the reaction

Recent applications of porphyrins as photocatalysts in organic synthesis: batch and continuous flow approaches

• Rodrigo Costa e Silva,
• Luely Oliveira da Silva,
• Aloisio de Andrade Bartolomeu,
• Timothy John Brocksom and
• Kleber Thiago de Oliveira

Beilstein J. Org. Chem. 2020, 16, 917–955, doi:10.3762/bjoc.16.83

• formation started in 2016 with the report from Gryko’s group on the photoredox α-alkylation of aldehydes with diazo compounds using 1 mol % of TPP or ZnTPP as photocatalyst [10] (Scheme 1), thus obtaining functionalized aldehydes in 47–90% yields. These results are similar to those previously reported by

Preparation and in situ use of unstable N-alkyl α-diazo-γ-butyrolactams in Rh^II-catalyzed X–H insertion reactions

• Maria Eremeyeva,
• Daniil Zhukovsky,
• Dmitry Dar’in and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2020, 16, 607–610, doi:10.3762/bjoc.16.55

• , the reactions tended to yield enamine adducts. Keywords: in situ reactions; N-alkyl 2-pyrrolidones; RhII-catalyzed insertion reactions; stability of diazo compounds; Introduction Recently, we described the first synthesis and subsequent transformations of a rare type of cyclic α-diazocarbonyl

• led to decomposition of the diazo compounds 4a–c), and addition of an alcohol, a thiol, or an aromatic amine along with a RhII catalyst resulted in a rapid insertion reaction and the isolation of the desired α-substituted γ-lactams 7a–o in modest yields (Scheme 1). It should be noted that, after some

• substantially expanded, thereby making this approach more useful for potential medicinal chemistry exploration of these disubstituted γ-lactams. Previously reported uses of α-diazo-γ-butyrolactams 1 and 4. Generation and in situ RhII-catalyzed X–H insertion reactions of the diazo compounds 4a–c. Conditions

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

• moieties. One year later, the group of Goossen demonstrated the direct conversion of diazo compounds into trifluoromethylselenolated products using a catalytic amount of copper(I) thiocyanate (Scheme 11) [28][29]. The reaction proceeded under mild conditions, and the desired products were usually obtained

Cyclopropanation–ring expansion of 3-chloroindoles with α-halodiazoacetates: novel synthesis of 4-quinolone-3-carboxylic acid and norfloxacin

• Sara Peeters,
• Linn Neerbye Berntsen,
• Pål Rongved and
• Tore Bonge-Hansen

Beilstein J. Org. Chem. 2019, 15, 2156–2160, doi:10.3762/bjoc.15.212

• decomposition of diazo compounds, are particularly versatile intermediates in organic synthesis, as they partake in cyclopropanation and C–H insertion reactions with high levels of selectivity [2]. This transition-metal-catalyzed carbene transfer has emerged as a mild and attractive route to indole

Formation of an unexpected 3,3-diphenyl-3H-indazole through a facile intramolecular [2 + 3] cycloaddition of the diazo intermediate

• Andrew T. King,
• Hugh G. Hiscocks,
• Lidia Matesic,
• Mohan Bhadbhade,
• Roger Bishop and
• Alison T. Ung

Beilstein J. Org. Chem. 2019, 15, 1347–1354, doi:10.3762/bjoc.15.134

• ]. More recently, the formation of cyclic 3,3-disubstituted 3H-indazoles was reported to form mainly through the [2 + 3] cycloaddition of diazo compounds with arynes under mild reaction conditions [29][30][31]. However, none of these contained a 2-diphenylmethyl (benzhydryl) aniline system, as found in

Reusable and highly enantioselective water-soluble Ru(II)-Amm-Pheox catalyst for intramolecular cyclopropanation of diazo compounds

• Hamada S. A. Mandour,
• Yoko Nakagawa,
• Masaya Tone,
• Hayato Inoue,
• Nansalmaa Otog,
• Ikuhide Fujisawa,
• Soda Chanthamath and
• Seiji Iwasa

Beilstein J. Org. Chem. 2019, 15, 357–363, doi:10.3762/bjoc.15.31

• intramolecular cyclopropanation of a variety of diazo compounds such as diazoacetates and diazoacetamides in a biphasic medium. Diazoacetates were tested in our catalytic system because they are widely used for intramolecular cyclopropanation reactions and also the resulted lactones are widely distributed in

• cyclopropanation using various diazo compounds with Ru(II)-Amm-Pheox Several diazoacetates and diazoacetamides were tested for asymmetric intramolecular cyclopropanation reactions using Ru(II)-Amm-Pheox catalyst (cat. 2) in H2O/ether biphasic medium as shown in Table 1. A diazo compound derived from allyl

Synthesis of 1,2-divinylcyclopropanes by metal-catalyzed cyclopropanation of 1,3-dienes with cyclopropenes as vinyl carbene precursors

• Jesús González,
• Alba de la Fuente,
• María J. González,
• Laura Díez de Tejada,
• Luis A. López and
• Rubén Vicente

Beilstein J. Org. Chem. 2019, 15, 285–290, doi:10.3762/bjoc.15.25

• –vinyl carbenes generated from vinyldiazoacetates (Scheme 1b) [14][15][16]. This reaction has been fruitfully exploited, although it is inherently limited by the restricted availability of potentially explosive diazo compounds. Consequently, the use of alternative vinyl carbene precursors is highly