A versatile way for the synthesis of monomethylamines by reduction of N-substituted carbonylimidazoles with the NaBH₄/I₂ system

• Lin Chen,
• Xuan Zhou,
• Zhiyong Chen,
• Changxu Wang,
• Shunjie Wang and
• Hanbing Teng

Beilstein J. Org. Chem. 2022, 18, 1032–1039, doi:10.3762/bjoc.18.104

• ][31] and carbon dioxide (CO2) [32][33][34][35][36][37][38][39] have been developed for the N-methylation of amines. However, these N-alkylation methods often require the employment of expensive catalysts, and the N-alkylation of primary amines generally does not stop with monomethylation as expected

Synthesis of odorants in flow and their applications in perfumery

• Merlin Kleoff,
• Paul Kiler and
• Philipp Heretsch

Beilstein J. Org. Chem. 2022, 18, 754–768, doi:10.3762/bjoc.18.76

• min isoamyl acetate (10) is obtained in 59% yield according to GC analysis [26]. Related methods for the enzyme-catalyzed acetylation of isoamyl alcohol (9) have been developed utilizing biphasic systems, supercritical carbon dioxide as a solvent, or packed-bed reactors with immobilized enzymes [27

• and warm odor; interestingly, it is also strongly antiseptic [9]. In 2005, Poliakoff and co-workers developed a synthesis of thymol by alkylation of m-cresol (39) in supercritical carbon dioxide (scCO2) using γ-Al2O3 in a packed-bed reactor (Scheme 9) [40]. In the presence of Brønsted-acidic Nafion

Menadione: a platform and a target to valuable compounds synthesis

• Acácio S. de Souza,
• Ruan Carlos B. Ribeiro,
• Dora C. S. Costa,
• Fernanda P. Pauli,
• David R. Pinho,
• Matheus G. de Moraes,
• Fernando de C. da Silva,
• Luana da S. M. Forezi and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

• ]. Different NbSBA-15 catalysts were evaluated and with the optimized reaction conditions, menadione (10) was synthetized in 100% conversion and 97.3% selectivity using NbSBA-15(2.2 pH) and H2O2 [69]. Sulman and co-workers, for instance, reported the synthesis of menadione (10) using supercritical (SC) carbon

• dioxide as green solvent [70]. The authors studied the oxidation using three metal-supported hypercrosslinked polystyrene (HPS) catalysts, which were Au (5%)/HPS, Pd (5%)/HPS and Pt (5%)/HPS, in SC CO2 medium. The best conversion (89%) was obtained with Au (5%)/HPS, using CO2 (150 bar), and a mixture of

Photoredox catalysis in nickel-catalyzed C–H functionalization

• Lusina Mantry,
• Rajaram Maayuri,
• Vikash Kumar and
• Parthasarathy Gandeepan

Beilstein J. Org. Chem. 2021, 17, 2209–2259, doi:10.3762/bjoc.17.143

• reported by Liu and co-workers [130]. Here, stoichiometric quantities of quinuclidine were used to get optimal results. Carboxylation Over the past few decades, significant attention has been devoted to exploit carbon dioxide (CO2) as the C1 resource [131][132]. In particular, the C–H functionalization

Icilio Guareschi and his amazing “1897 reaction”

• Gian Cesare Tron,
• Alberto Minassi,
• Giovanni Sorba,
• Mara Fausone and
• Giovanni Appendino

Beilstein J. Org. Chem. 2021, 17, 1335–1351, doi:10.3762/bjoc.17.93

• 10 is entirely due to mesomeric effects, as expressed by the possibility to formulate two identical resonance forms, 10a and 10b, for the undissociated system (Scheme 6). It has been remarked that life is basically a hydrogen transfer to carbon dioxide, outrageously approximated by the equation CO2

Synthetic reactions driven by electron-donor–acceptor (EDA) complexes

• Zhonglie Yang,
• Yutong Liu,
• Kun Cao,
• Xiaobin Zhang,
• Hezhong Jiang and
• Jiahong Li

Beilstein J. Org. Chem. 2021, 17, 771–799, doi:10.3762/bjoc.17.67

• * under irradiation with light. Then, radical intermediate 113 is afforded via intermolecular electron transfer, followed by removing one molecule of carbon dioxide to give radical intermediate 114. Species 115 is formed through radical coupling in 114, providing the target product 111 with the release of

• electron-donor catalyst to form an EDA complex with electron acceptor 158, and then a molecule of carbon dioxide was removed under 455 nm light irradiation, giving decarboxylation product 159 (Scheme 55). It was found that many ester groups can be activated by the structural motif of tetrachlorophthalimide

Valorisation of plastic waste via metal-catalysed depolymerisation

• Francesca Liguori,
• Carmen Moreno-Marrodán and
• Pierluigi Barbaro

Beilstein J. Org. Chem. 2021, 17, 589–621, doi:10.3762/bjoc.17.53

Synthesis of N-perfluoroalkyl-3,4-disubstituted pyrroles by rhodium-catalyzed transannulation of N-fluoroalkyl-1,2,3-triazoles with terminal alkynes

• Olga Bakhanovich,
• Viktor Khutorianskyi,
• Vladimir Motornov and
• Petr Beier

Beilstein J. Org. Chem. 2021, 17, 504–510, doi:10.3762/bjoc.17.44

• an electrophile, the crude product 2a was treated with butyllithium, followed by the reaction with carbon dioxide to afford pyrrole carboxylic acid 6 in a good overall yield (Scheme 5). The trifluoromethyl group on the nitrogen was not affected by these highly basic reaction conditions. The mechanism

All-carbon [3 + 2] cycloaddition in natural product synthesis

• Zhuo Wang and
• Junyang Liu

Beilstein J. Org. Chem. 2020, 16, 3015–3031, doi:10.3762/bjoc.16.251

•  3A). Trost and co-workers proposed that the catalytic mechanism involves an oxidative addition of palladium(0) into 62 affording the η3-Pd TMM complex A [37] (Scheme 3B). Methyl trimethylsilyl carbonate (64) is formed as side product, which is in equilibrium with carbon dioxide and methyl

• trimethylsilyl ether. The electron-rich end of complex A attacks the carbon dioxide to give carboxylate B. Migration of the TMS group on carboxylate B generates the 1,3-dipole on C in the form of TMS carboxylate. An intermolecular [3 + 2] cycloaddition of C and alkene D (see Scheme 3B, inset) gives the

A proposed sustainability index for synthesis plans based on input provenance and output fate: application to academic and industrial synthesis plans for vanillin as a case study

• John Andraos

Beilstein J. Org. Chem. 2020, 16, 2346–2362, doi:10.3762/bjoc.16.196

• was considered a renewable input for the oxidation of lignosulfonic acid liquors since it is produced as a natural waste byproduct of photosynthesis. (6) Spent vanilla beans were considered reusable waste since they can be composted into biomass. (7) Supercritical carbon dioxide was considered

• Mexican group SFE plans. For the case of supercritical carbon dioxide used as an extraction solvent, the main drawback is that industrial carbon dioxide is classified as originating from a non-renewable mineral resource (mainly calcium carbonate) and that the mass ratio of sCO2 solvent to vanilla beans is

Mechanochemical green synthesis of hyper-crosslinked cyclodextrin polymers

• Alberto Rubin Pedrazzo,
• Fabrizio Caldera,
• Marco Zanetti,
• Silvia Lucia Appleton,
• Nilesh Kumar Dhakar and
• Francesco Trotta

Beilstein J. Org. Chem. 2020, 16, 1554–1563, doi:10.3762/bjoc.16.127

• nearly quantitative yields, with the release of carbon dioxide and formation of IMH. The reaction kinetics of alcohols with N,N'-carbonyldiimidazole were generally slower, so the presence of reactive IM moieties may be particularly interesting for an easy functionalization via reaction with nucleophilic

An overview on disulfide-catalyzed and -cocatalyzed photoreactions

• Yeersen Patehebieke

Beilstein J. Org. Chem. 2020, 16, 1418–1435, doi:10.3762/bjoc.16.118

• generates the active species Mes–Acr–Me*. Then, the single-electron oxidation of the deprotonated carboxylic acid 52 with Mes–Acr–Me* results in the formation of an acyloxyl radical 53. The subsequent rearrangement of the radical 53 gives a carbon-centered radical 54 and carbon dioxide. The phenyl thiyl

Activated carbon as catalyst support: precursors, preparation, modification and characterization

• Melanie Iwanow,
• Tobias Gärtner,
• Volker Sieber and
• Burkhard König

Beilstein J. Org. Chem. 2020, 16, 1188–1202, doi:10.3762/bjoc.16.104

• incorporation of the activating substances [16]. Several literature reports show a higher reactivity of steam as mild oxidizing reagent compared to carbon dioxide. Nevertheless, no clear tendencies were found regarding the pore development [87][88][89][90][91]. Rodríguez-Reinoso et al. and Zamora and co-workers

• macropores are formed) compared to carbon dioxide [64][87]. Kalderis et al. prepared activated carbons from bagasse and rice husk by physical and chemical activation. They found that physical activation results in significantly lower surface areas compared to the surface obtained by chemical activation with

• found that KOH plays a crucial role in the formation of porosity. Metallic potassium is formed during the carbonization of the carbon precursor, which intercalates in the carbon structure and is responsible for further release of carbon dioxide, carbon monoxide and hydrogen [71]. According to Marsh and

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

• also can be applied to the reduction of carbon dioxide (CO2). Many photocatalytic materials containing porphyrins have been developed for CO2 reactions in organic synthesis, including photoinduced transformations [52][53][54][55]. Nagaraja and co-workers reported the first porphyrin-based MOF for

• photoinduced cycloaddition of carbon dioxide with epoxides [56]. The synthesis of a 3D supramolecular framework, [{Mn(TCPP)0.5(H2O)}·2H2O]n, where Mn(TCPP) is Mn(II) meso-tetrakis(4-carboxyphenyl)porphyrin, was derived from MnCl2·6H2O and TCPP. The cycloaddition product, a cyclic carbonate, was obtained from

Architecture and synthesis of P,N-heterocyclic phosphine ligands

• Wisdom A. Munzeiwa,
• Bernard Omondi and
• Vincent O. Nyamori

Beilstein J. Org. Chem. 2020, 16, 362–383, doi:10.3762/bjoc.16.35

• carbon dioxide and phenyllithium gives the phosphine ferrocene carboxylic acid 152 as the major reagent. Oxidation of the phosphine using hydrogen peroxide generated the phosphine oxide 153. In situ chlorination of the carboxylic acid followed by addition of the chiral amino alcohols gave the phosphoryl

Recent developments in photoredox-catalyzed remote ortho and para C–H bond functionalizations

• Rafia Siddiqui and
• Rashid Ali

Beilstein J. Org. Chem. 2020, 16, 248–280, doi:10.3762/bjoc.16.26

• functional materials [56], the reduction of carbon dioxide [57][58][59], etc. Additionally, inorganic chemists have utilized inorganic photocatalysts for functional components, viz, doping [60][61][62][63][64][65][66][67], encapsulated guests [68][69][70][71][72][73][74], molecular machines [75][76][77][78

Synthesis of dipolar molecular rotors as linkers for metal-organic frameworks

• Sebastian Hamer,
• Fynn Röhricht,
• Marius Jakoby,
• Ian A. Howard,
• Xianghui Zhang,
• Christian Näther and
• Rainer Herges

Beilstein J. Org. Chem. 2019, 15, 1331–1338, doi:10.3762/bjoc.15.132

• acid 1 using cesium fluoride under a carbon dioxide atmosphere. Difluoro- and dicyanobenzothiadiazole compounds 2 and 3 Substituted benzothiadiazole derivatives are well studied in the literature and are of great interest in organic photovoltaics and electronics. As there are no reports of such

• -benzothiadiazole (10) could be obtained in a Sonogashira reaction with trimethylsilylacetylene. Conversion to the dicarboxylic acid 2 was achieved using cesium fluoride under a carbon dioxide atmosphere. Not quite as straightforward was the synthesis of the dicyano derivative 3. While the synthesis of 5,6-dicyano

• polymerisation of the acetylides. No deprotected terminal acetylene was observed. To avoid polymerization, the solvent was changed to acetonitrile and the temperature was lowered to 0 °C. Additionally, carbon dioxide was not just used as the reaction atmosphere, but directly bubbled through the solution

An anomalous addition of chlorosulfonyl isocyanate to a carbonyl group: the synthesis of ((3aS,7aR,E)-2-ethyl-3-oxo-2,3,3a,4,7,7a-hexahydro-1H-isoindol-1-ylidene)sulfamoyl chloride

• Aytekin Köse,
• Aslı Ünal,
• Ertan Şahin,
• Uğur Bozkaya and
• Yunus Kara

Beilstein J. Org. Chem. 2019, 15, 931–936, doi:10.3762/bjoc.15.89

• release of carbon dioxide from the molecule. We performed theoretical computations to better understand the reaction mechanism shown in Scheme 4 (Figure 3). For this purpose, we employed density functional theory (DFT) calculations and performed geometric optimizations using the B3LYP functional [19][20

Cyclopropene derivatives of aminosugars for metabolic glycoengineering

• Jessica Hassenrück and
• Valentin Wittmann

Beilstein J. Org. Chem. 2019, 15, 584–601, doi:10.3762/bjoc.15.54

• . Cell growth conditions: HEK 293T (human embryonic kidney) cells were grown in Dulbecco’s Modified Eagle’s Medium (DMEM) containing fetal bovine serum (FBS, 10%) and penicillin and streptomycin (each 100 U mL−1). Cells were incubated under carbon dioxide (5%) in a water-saturated incubator at 37 °C. The

Back to the future: Why we need enzymology to build a synthetic metabolism of the future

• Tobias J. Erb

Beilstein J. Org. Chem. 2019, 15, 551–557, doi:10.3762/bjoc.15.49

• require less energy (ATP, redox power and/or photons) and can be supposedly operated at higher catalytic rates compared to natural carbon fixation. Accordingly, the synthetic CO2-fixation cycles should be able to convert more carbon dioxide with less energy in a given time and hence succeed natural

Synthesis and selected transformations of 2-unsubstituted 1-(adamantyloxy)imidazole 3-oxides: straightforward access to non-symmetric 1,3-dialkoxyimidazolium salts

• Grzegorz Mlostoń,
• Małgorzata Celeda,
• Katarzyna Urbaniak,
• Marcin Jasiński,
• Vladyslav Bakhonsky,
• Peter R. Schreiner and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2019, 15, 497–505, doi:10.3762/bjoc.15.43

• evolution of carbon dioxide ceased. The mixture was stirred overnight, filtered and the filtrate was evaporated to dryness. The crude product was triturated again with diethyl ether and after few minutes filtered off. In some instances, products obtained thereby were dried over freshly prepared molecular

Synthesis of unnatural α-amino esters using ethyl nitroacetate and condensation or cycloaddition reactions

• Glwadys Gagnot,
• Vincent Hervin,
• Eloi P. Coutant,
• Sarah Desmons,
• Racha Baatallah,
• Victor Monnot and
• Yves L. Janin

Beilstein J. Org. Chem. 2018, 14, 2846–2852, doi:10.3762/bjoc.14.263

• reduction of 13 using zinc and hydrochloric acid gave the target α-amino ester 14 in an 85% yield. To avoid the recourse to more rare and/or expensive heterocyclic aldehydes, we also tried synthetic approaches based on [2 + 3] cycloadditions. As depicted in Scheme 3, the carbon dioxide-producing reaction

Copolymerization of epoxides with cyclic anhydrides catalyzed by dinuclear cobalt complexes

• Yo Hiranoi and
• Koji Nakano

Beilstein J. Org. Chem. 2018, 14, 2779–2788, doi:10.3762/bjoc.14.255

• demonstrate high and/or unique catalytic performances in the epoxide/CA copolymerization [23][32][33][34][35][36][37][38][39]. Recently, we have reported the dinuclear cobalt–salen complexes as catalysts for the copolymerization of epoxides with carbon dioxide (CO2), affording superior catalytic activity

Quinolines from the cyclocondensation of isatoic anhydride with ethyl acetoacetate: preparation of ethyl 4-hydroxy-2-methylquinoline-3-carboxylate and derivatives

• Nicholas G. Jentsch,
• Jared D. Hume,
• Emily B. Crull,
• Samer M. Beauti,
• Amy H. Pham,
• Julie A. Pigza,
• Jacques J. Kessl and
• Matthew G. Donahue

Beilstein J. Org. Chem. 2018, 14, 2529–2536, doi:10.3762/bjoc.14.229

• ester carbonyl of the isatoic anhydride forming tetrahedral intermediate A. Subsequent collapse of the sp3-hybridized carbon to the ketone B with concomitant expulsion of carbon dioxide and enolization affords the ketone C. The anion of the aniline nitrogen then attacks the ketone carbonyl via

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

• Tetsuaki Fujihara Yasushi Tsuji Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan 10.3762/bjoc.14.221 Abstract Carbon dioxide (CO2) is one of the most important materials as renewable chemical feedstock. In this

• [2 + 2 + 2] cycloaddition of diynes and CO2 proceeds to afford pyrones. Keywords: carbon dioxide; carboxylation; cobalt; homogeneous catalysts; rhodium; Introduction Carbon dioxide (CO2) is one of the most important materials as renewable feedstock [1][2][3][4]. However, the thermodynamic and