Recent advances in organocatalytic atroposelective reactions

• Henrich Szabados and
• Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

• the final step of the reaction, ring opening by the C–C bond cleavage yields the desired product 203. The first phosphoric acid C39-catalyzed asymmetric cycloaddition–elimination cascade reaction of 2-naphthol or phenol enamide derivatives 204 with azonaphthalenes 205 was done by Xu et al. in 2021

Advances in radical peroxidation with hydroperoxides

• Oleg V. Bityukov,
• Pavel Yu. Serdyuchenko,
• Andrey S. Kirillov,
• Gennady I. Nikishin,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249

• in Kwon’s review [34]. Cu-catalyzed oxygen atom transfer with TBHP were discussed in the review [35]. The review by Xiao considered visible light-driven C–C bond cleavage enabled with organic peroxides [36]. This comprehensive review summarizes all ever published studies on radical peroxidation with

A review of recent advances in electrochemical and photoelectrochemical late-stage functionalization classified by anodic oxidation, cathodic reduction, and paired electrolysis

• Nian Li,
• Ruzal Sitdikov,
• Ajit Prabhakar Kale,
• Joost Steverlynck,
• Bo Li and
• Magnus Rueping

Beilstein J. Org. Chem. 2024, 20, 2500–2566, doi:10.3762/bjoc.20.214

Cofactor-independent C–C bond cleavage reactions catalyzed by the AlpJ family of oxygenases in atypical angucycline biosynthesis

• Jinmin Gao,
• Liyuan Li,
• Shijie Shen,
• Guomin Ai,
• Bin Wang,
• Fang Guo,
• Tongjian Yang,
• Hui Han,
• Zhengren Xu,
• Guohui Pan and
• Keqiang Fan

Beilstein J. Org. Chem. 2024, 20, 1198–1206, doi:10.3762/bjoc.20.102

• distinctive subset of compounds, including jadomycin, gilvocarcin, kinamycin, fluostatin, and lomaiviticin, arises from typical angucycline intermediates via oxidative C–C bond cleavage and subsequent ring rearrangement reactions. These atypical angucyclines exhibit intriguing chemical structures and various

• bond cleavage, ring opening, and rearrangement reactions, yielding the respective products. Furthermore, the reactions of 8 catalyzed by JadG and AlpJ could be quenched by superoxide dismutase (SOD), supporting a catalytic mechanism involving the generation of a substrate radical and the superoxide

• , Supporting Information File 1) [21][22]. In this study, we reveal the previously undisclosed facet that AlpJ-family oxygenases can function as cofactor-independent oxygenases when the hydroquinone intermediate CR1 (8) serves as the substrate. In this context, the enzymes autonomously catalyze oxidative C–C

Synthesis of aliphatic nitriles from cyclobutanone oxime mediated by sulfuryl fluoride (SO₂F₂)

• Xian-Lin Chen and
• Hua-Li Qin

Beilstein J. Org. Chem. 2023, 19, 901–908, doi:10.3762/bjoc.19.68

• ][26][27][28][29], a synthesis method for δ-olefin-containing aliphatic nitriles by the radical C–C bond cleavage of cycloketone oxime ester derivatives was developed by Shi’s group (Scheme 2a) [30], which emerged as an efficient strategy to construct C(sp2)–C(sp3) bonds [31][32][33]. Later, Xiao [34

Electrochemical formal homocoupling of sec-alcohols

• Kosuke Yamamoto,
• Kazuhisa Arita,
• Masashi Shiota,
• Masami Kuriyama and
• Osamu Onomura

Beilstein J. Org. Chem. 2022, 18, 1062–1069, doi:10.3762/bjoc.18.108

• -2a was subjected to the present reaction conditions, oxidative C–C bond cleavage of dl-2a proceeded to give the corresponding ketone 3a (Scheme 5b) [48]. Recovered 2a was found to be a mixture of dl and meso isomers, indicating that homocoupling of in situ-generated ketone 3a occurred under the

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

• selection of the reagents and catalysts. These have an influence on the mechanism and regioselectivity of the C–C bond cleavage. Although there are several different mechanisms for ring-opening reactions, in most cases there is a cleavage of the most weakened C–C bond due to the fluorine effect. This C–C

• in 105, which is associated with a difference in the regioselectivity of the C–C bond cleavage. The dissociation of the tosylate 104 to generate a cyclopropylmethyl carbocation A was accompanied by the cleavage of the proximal bond to form homoallylic products. The regioselectivity of the ring

• imines 115, which led to alkylideneazetidines 116 (Scheme 52) [102]. The MgI2 acted as a Lewis acid and reducing agent, effecting the distal C–C bond cleavage in 113a to form an allenyl ketone, or an equivalent fluoro,iodo-enone species, either of which could then have added to the imine 115 and led to

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

• tautomers was possible, revealing them as significant intermediates for the mechanism elucidation. Keywords: α-alkylthio esters; α-alkylthio ketones; Bunte salts; C–C bond cleavage; β-keto esters; Introduction During the last ten years, sodium S-organyl sulfurothioates, also known as Bunte salts, were

• , and related compounds. Some of them are catalyzed by expensive transition metals, such as gold, iridium, palladium, and titanium. More recently, the selective formation of C–S bonds using 1,3-dicarbonyl compounds, followed by a C–C bond cleavage has emerged as a versatile and less expensive protocol

• ). However, when compound 5 reacted with sodium S-benzyl sulfurothioate (2a), the enol product 6 was obtained in 86% yield after 2 h at 100 °C. In this case even a longer reaction time and a higher temperature were not effective to achieve the C–C bond cleavage. This interesting result also gave us the

Oxime radicals: generation, properties and application in organic synthesis

• Igor B. Krylov,
• Stanislav A. Paveliev,
• Alexander S. Budnikov and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2020, 16, 1234–1276, doi:10.3762/bjoc.16.107

• reactions of oxime radicals. These reactions are classified into cyclizations involving C–H bond cleavage and cyclizations involving a double C=C bond cleavage. Keywords: iminoxyl radicals; isoxazolines; oxidative cyclization; oxime radicals; oximes; Introduction Free radicals in which an unpaired

Isolation and characterisation of irinans, androstane-type withanolides from Physalis peruviana L.

• Annika Stein,
• Dave Compera,
• Bianka Karge,
• Mark Brönstrup and
• Jakob Franke

Beilstein J. Org. Chem. 2019, 15, 2003–2012, doi:10.3762/bjoc.15.196

• A (2). Our experiments suggest that irinan A (2) and most likely all androwithanolides are not isolation artefacts but true natural products, which require an oxidative enzyme to facilitate the C–C bond cleavage. Future studies will shed light on the enzymatic basis of androwithanolide formation

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

• intermediate A. The attack of the ortho-position of the pyridinium moiety by the nucleophilic oxygen of intermediate A is then proposed to generate cyclic oxazolopyridine intermediate B [42][43]. The intermediate B then undergoes a rearrangement to afford N-alkylated benzamide 3 via a C–C bond cleavage with

• pyridinium salts of phenacyl bromides for the construction of amides and esters in the presence of base via oxidative C–C bond cleavage. The promising features of this methodology include the absence of a metal catalyst, employing a simple inorganic base and operational simplicity for application in organic

Oxidative radical ring-opening/cyclization of cyclopropane derivatives

• Yu Liu,
• Qiao-Lin Wang,
• Zan Chen,
• Cong-Shan Zhou,
• Bi-Quan Xiong,
• Pan-Liang Zhang,
• Chang-An Yang and
• Quan Zhou

Beilstein J. Org. Chem. 2019, 15, 256–278, doi:10.3762/bjoc.15.23

• introduced the Na2S2O8-promoted ring-opening/alkynylation of cyclopropanols 91 with ethynylbenziodoxolones (EBX) 116 for the synthesis of the alkynylated ketones 117 (Scheme 27) [107]. This reaction involved a C–C bond cleavage, radical rearrangement, and C–C bond formation, and showed a wide substrates

• 124 (Scheme 31) [111]. This transformation involved a C–C bond cleavage and two C–C bond formations, and showed excellent functional group tolerance, satisfactory yields and operational simplicity. In 2017, Mohr’s group proposed a straightforward approach to synthesize β-fluorinated ketones 114 by

An overview on recent advances in the synthesis of sulfonated organic materials, sulfonated silica materials, and sulfonated carbon materials and their catalytic applications in chemical processes

• Hashem Sharghi,
• Pezhman Shiri and
• Mahdi Aberi

Beilstein J. Org. Chem. 2018, 14, 2745–2770, doi:10.3762/bjoc.14.253

• amount of HPW on silica decreased the yield of reaction [62]. The silica sulfuric acid (SSA) catalyst was synthesized by the treatment of silica gel with sulfuryl chloride under room temperature stirring. The catalyst was used in the acylation of amines with 1,3-diketones via C–C bond cleavage. Various

Glycosylation reactions mediated by hypervalent iodine: application to the synthesis of nucleosides and carbohydrates

• Yuichi Yoshimura,
• Hideaki Wakamatsu,
• Yoshihiro Natori,
• Yukako Saito and
• Noriaki Minakawa

Beilstein J. Org. Chem. 2018, 14, 1595–1618, doi:10.3762/bjoc.14.137

• alternative method for constructing glycosidic bonds of nucleoside derivatives by using a glycal as sugar donor. Its usefulness was proved by applying the reaction to synthesize new nucleoside derivatives as mentioned above. Synthesis of acyclic nucleosides It is known that the oxidative C–C bond cleavage of

Spectroelectrochemical studies on the effect of cations in the alkaline glycerol oxidation reaction over carbon nanotube-supported Pd nanoparticles

• Dennis Hiltrop,
• Steffen Cychy,
• Karina Elumeeva,
• Wolfgang Schuhmann and
• Martin Muhler

Beilstein J. Org. Chem. 2018, 14, 1428–1435, doi:10.3762/bjoc.14.120

• varying the potential between 0.77 and 1.17 V vs RHE: at low potentials oxidized C3 species such as mesoxalate and tartronate were formed predominantly, and with increasing potentials C2 and C1 species originating from C–C bond cleavage were identified. The tendency to produce carbonate was found to be

• or glyoxylate that are only found at higher potentials as intermediate species towards oxalate [13]. The product assignment clearly indicates that increasing potentials favor C–C bond cleavage. Bond scission is likely to proceed via highly oxidized C3 species that are prone to undergo C–C scission

5-Aminopyrazole as precursor in design and synthesis of fused pyrazoloazines

• Ranjana Aggarwal and
• Suresh Kumar

Beilstein J. Org. Chem. 2018, 14, 203–242, doi:10.3762/bjoc.14.15

• first direct conversion of acenaphthenequinone to a naphthoic acid fragment via C–C bond cleavage in a single step. Recently, D. Anand et al. [63] have reported the synthesis of pyrazolo[3,4-b]pyridine derivatives 71 and 72 through the multicomponent reaction of 1-aryl-3-indolyl-5-aminopyrazoles 16

• than conventional heating methods. Recently, Boruah et al. [93] reported an unprecedented synthesis of pyrazolo[1,5-a]pyrimidines 132 involving a C–C bond cleavage through KOt-Bu-catalyzed condensation of 1,3,5-trisubstituted pentane-1,5-diones 131 with substituted 5-aminopyrazoles 16 in ethanol

Quinone-catalyzed oxidative deformylation: synthesis of imines from amino alcohols

• Xinyun Liu,
• Johnny H. Phan,
• Benjamin J. Haugeberg,
• Shrikant S. Londhe and
• Michael D. Clift

Beilstein J. Org. Chem. 2017, 13, 2895–2901, doi:10.3762/bjoc.13.282

• synthetic versatility of quinone-catalyzed oxidative C–C bond cleavage. Keywords: catalysis; deformylation; organic synthesis; organocatalysis; Introduction Imines are extremely versatile intermediates in organic chemistry [1][2][3]. Consequently, many synthetic methods have been developed for the

• the preparation of imines [5][6]. The majority of these methods involve cleavage of a C−H bond at the α-position of an amine substrate [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. Methods that deliver imines through amine α-C−C bond cleavage are far less

• decarboxylative homologation of α-amino acids [32], which demonstrated for the first time that quinone organocatalysts can be utilized to enable oxidative C–C bond cleavage to provide versatile imine intermediates. To further exploit the utility of this chemistry, we sought to develop a new method for the

The reductive decyanation reaction: an overview and recent developments

• Jean-Marc R. Mattalia

Beilstein J. Org. Chem. 2017, 13, 267–284, doi:10.3762/bjoc.13.30

• iminyl anion intermediate 27. The latter easily isomerizes to its isomer 28 where a sodium cation–π-interaction occurs. The last step involves a C–C bond cleavage and proton transfer with elimination of NaCN (Scheme 12). This proton transfer occurs with retention of configuration as experimentally

• an unique hydride-donor reactivity [82]. An addition–elimination mechanism has been previously proposed for the LiAlH4 promoted decyanation of 2,2-diphenylpropionitrile and related nitriles. In such pathways, the phenyl groups probably favor the C–C bond cleavage by stabilizing the incipient negative

Rearrangements of organic peroxides and related processes

• Ivan A. Yaremenko,
• Vera A. Vil’,
• Dmitry V. Demchuk and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162

• rearrangement is a protic or Lewis acid-promoted rearrangement of hydroperoxides A resulting in a C–C bond cleavage to form alcohol B and carbonyl compound C (Scheme 50) [313]. The Hock rearrangement is a key step in the cumene process, which is used for the industrial production of phenol (170) and acetone

Base metal-catalyzed benzylic oxidation of (aryl)(heteroaryl)methanes with molecular oxygen

• Hans Sterckx,
• Johan De Houwer,
• Carl Mensch,
• Wouter Herrebout,
• Kourosch Abbaspour Tehrani and
• Bert U. W. Maes

Beilstein J. Org. Chem. 2016, 12, 144–153, doi:10.3762/bjoc.12.16

• anilines resulting in the formation of 2-aryl-α-ketoacetamides was reported by Jiao [22] and a closely related intramolecular variant leading to isatins has been published by Ilangovan [23]. A remarkable Cu-catalyzed chemoselective oxidative C–C bond cleavage of methyl ketones was reported by the group of

Recent highlights in biosynthesis research using stable isotopes

• Jan Rinkel and
• Jeroen S. Dickschat

Beilstein J. Org. Chem. 2015, 11, 2493–2508, doi:10.3762/bjoc.11.271

• incorporation of labeled Gly into the methyl group was rationalized by glycine degradation, directing the labeling via tetrahydrofolate and SAM into aspirochlorine biosynthesis. The conversion of the Phe residue to Gly may proceed through either oxidative C–C bond cleavage or a retro-aldol reaction in 18, in

Recent advances in copper-catalyzed C–H bond amidation

• Jie-Ping Wan and
• Yanfeng Jing

Beilstein J. Org. Chem. 2015, 11, 2209–2222, doi:10.3762/bjoc.11.240

• ] reported the copper-catalyzed, tert-butyl hydroperoxide (TBHP)-assisted C–H amidation of tertiary amines 1. By heating at 80 °C, the C–H bond in dimethylaniline underwent direct amidation to provide products 3 in the presence of amides 2. On the other hand, the dephenylation transformation via C–C bond

• cleavage took place as the main route when N-phenyl-N-methylaniline was employed as the alternative reactant, which led to the production of 3 as the main products, while corresponding products 4 via C–H bond amidation occurred as the minor ones. Notably, this kind of C–H amidation strategy could be

Copper-catalyzed aerobic radical C–C bond cleavage of N–H ketimines

• Ya Lin Tnay,
• Gim Yean Ang and
• Shunsuke Chiba

Beilstein J. Org. Chem. 2015, 11, 1933–1943, doi:10.3762/bjoc.11.209

• cleavage of N–H ketimines. Treatment of N–H ketimines having an α-sp3 hybridized carbon under Cu-catalyzed aerobic reaction conditions resulted in a radical fragmentation with C–C bond cleavage to give the corresponding carbonitrile and carbon radical intermediate. This radical process has been applied for

• the construction of oxaspirocyclohexadienones as well as in the electrophilic cyanation of Grignard reagents with pivalonitrile as a CN source. Keywords: C–C bond cleavage; copper; ketimines; molecular oxygen; radical; Introduction Alkylideneaminyl radicals (iminyl radicals) have been utilized for

• formation of the desired 6-membered azaspirocycle 3a’ was observed, while oxaspirocyclohexadienone 3a, biaryl alkene 4a, and p-tolunitrile (5a) were isolated in 29%, 32%, and 86% yields, respectively (Scheme 4). Oxaspirocyclohexadienone 3a was formed through C–C bond cleavage from N–H ketimine intermediate

Recent applications of ring-rearrangement metathesis in organic synthesis

• Sambasivarao Kotha,
• Milind Meshram,
• Priti Khedkar,
• Shaibal Banerjee and
• Deepak Deodhar

Beilstein J. Org. Chem. 2015, 11, 1833–1864, doi:10.3762/bjoc.11.199

• syntheses of virgidivarine and virgiboidine by employing an intramolecular ene–ene–yne domino RRM protocol in combination with an oxidative C–C bond cleavage. This protocol opens-up new opportunities for the construction of intricate dipiperidine-based targets in a stereoselective manner (Scheme 12). Lee

Organobase-catalyzed three-component reactions for the synthesis of 4H-2-aminopyrans, condensed pyrans and polysubstituted benzenes

• Moustafa Sherief Moustafa,
• Saleh Mohammed Al-Mousawi,
• Maghraby Ali Selim,
• Ahmed Mohamed Mosallam and
• Mohamed Hilmy Elnagdi

Beilstein J. Org. Chem. 2014, 10, 141–149, doi:10.3762/bjoc.10.11

• propiolate (4a) in the presence of L-proline to produce the penta-substituted benzene derivative 13b in 60% yield (Scheme 4). In order to explain this unusual finding, we proposed that malononitrile, perhaps formed under the reaction conditions by C–C bond cleavage promoted fragmentation of 8, adds to 9 to