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

• the presence of N-(2-bromophenylthio)succinimide 1’ and copper catalyst led to intermolecular sulfenoamination of alkenes and subsequent C–N coupling to produce dihydrobenzothiazine structures 27 in a one-pot manner. Furthermore, deprotection of the amine unit by K2CO3 and Na metal was performed in

α-(Aminomethyl)acrylates as acceptors in radical–polar crossover 1,4-additions of dialkylzincs: insights into enolate formation and trapping

• Angel Palillero-Cisneros,
• Paola G. Gordillo-Guerra,
• Fernando García-Alvarez,
• Olivier Jackowski,
• Franck Ferreira,
• Fabrice Chemla,
• Joel L. Terán and
• Alejandro Perez-Luna

Beilstein J. Org. Chem. 2023, 19, 1443–1451, doi:10.3762/bjoc.19.103

• of primary amines and tert-butylsulfinamide (preparation of compounds 5–7 and 8a–c). In a round-bottomed flask under argon, n-BuLi (1.0 equiv, soln. in heptane) was added dropwise to a THF (0.2 mol·L−1) solution of the appropriate primary amine or tert-butylsulfinamide (1.0 equiv) at −55 °C. The

Application of N-heterocyclic carbene–Cu(I) complexes as catalysts in organic synthesis: a review

• Nosheen Beig,
• Varsha Goyal and
• Raj K. Bansal

Beilstein J. Org. Chem. 2023, 19, 1408–1442, doi:10.3762/bjoc.19.102

• . Two complexes, 61 and 65 (see Scheme 21), were found equally efficient. The products were obtained in 95 to 99% yield and the range of functionalities tolerated included nitro, nitrile, ether, carbonyl, alcohol, and amine [35]. Gautier and co-workers studied the effect of the addition of aromatic N

• , generated from the tetranuclear complex, as the catalytically active species. 2.4 A3 reactions In recent years, the three component reaction of an aldehyde, a secondary amine and a terminal alkyne, known as A3 reaction to afford chiral propargylamines 140 has received much attention. The latter compounds

• multifunctional catalytic system 142 incorporating ruthenium nanoparticles (RuNPS) and an NHC–Cu–Cl complex supported on silica (Scheme 56). The catalyst, Ru@SiO2–[Cu(NHC)] was successfully applied to a one-pot tandem A3 reaction of an aldehyde, alkyne, and secondary amine followed by hydrogenation of the

One-pot nucleophilic substitution–double click reactions of biazides leading to functionalized bis(1,2,3-triazole) derivatives

• Hans-Ulrich Reissig and
• Fei Yu

Beilstein J. Org. Chem. 2023, 19, 1399–1407, doi:10.3762/bjoc.19.101

• (bromomethyl)benzene furnished geometrically differing bis(1,2,3-triazole) derivatives. The use of tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine (TBTA) as ligand for the click step turned out to be very advantageous. The compounds with 1,2-oxazinyl end groups can potentially serve as precursors of divalent

• converted into several multivalent compounds B by amine or amide bond formations [44][45][46][47]. The transformation of the corresponding azidopyrans and azidooxepanes C or E into multivalent 1,2,3-triazole derivatives D and F by Meldal–Sharpless cycloadditions with suitable alkynes proceeded generally in

• we examined the influence of the ligand tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine (TBTA) which has been identified by Sharpless et al. [58] as a very beneficial component in CuAAC reactions. After comprehensive optimization, we found that the addition of 0.2 equiv of this ligand not only

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

• indeed much more stable than PAF in serum, increases the formation of prostaglandin E2 from astrocyte cortical cell culture [103] and affect memory [104]. Ponpipom et al. have reported the synthesis of PAF-analogues featuring in sn-2 position either an azide, amine or acetamide group [79]. In each case

• trimethylamine to yield the phosphate 17.10 as an intermediate. Then, its reaction with trimethylamine produced the phosphocholine moiety and compound N3-PAF (17.11). Then, the amine (NH2-PAF) 17.12 was formed by catalytic hydrogenation and subsequently the (acetamido-PAF) 17.13 was formed by acetylation of the

• amine with acetic anhydride. It is worth noticing that acetamido-PAF 17.13 was previously reported following a different synthesis scheme starting from serine as chiral precursor [96][105]. Recently, is was reported that the acetamido-PAF 17.13 is an activator of the TRPV2 channel leading to

Acetaldehyde in the Enders triple cascade reaction via acetaldehyde dimethyl acetal

• Alessandro Brusa,
• Debora Iapadre,
• Maria Edith Casacchia,
• Alessio Carioscia,
• Giuliana Giorgianni,
• Giandomenico Magagnano,
• Fabio Pesciaioli and
• Armando Carlone

Beilstein J. Org. Chem. 2023, 19, 1243–1250, doi:10.3762/bjoc.19.92

• reaction for the synthesis of polyfunctionalized cyclohexenes bearing multiple stereocenters. The reaction is promoted by a chiral secondary amine, which is capable of catalyzing each step of the process activating the substrates through enamine and iminium ion catalysis towards a Michael/Michael/aldol

Enabling artificial photosynthesis systems with molecular recycling: A review of photo- and electrochemical methods for regenerating organic sacrificial electron donors

• Grace A. Lowe

Beilstein J. Org. Chem. 2023, 19, 1198–1215, doi:10.3762/bjoc.19.88

• -workers published a study in which they used a cyclic tertiary amine sacrificial donor that they had designed to be regenerated [32]. This was significant because instead of replacing amine sacrificial donors with redox mediators, this paper proposed an alternate strategy of an ex-situ regeneration of

• organic donors. The authors designed and synthesized a tertiary amine that could be oxidized and rehydrogenated. They used their amine to successfully replace triethylamine in a photocatalytic carbon dioxide reduction reaction from the literature and proved that the recyclable byproduct was formed. In

• . Carpenter and co-workers also proposed, but did not test, recycling their amine with electrochemistry and light [32]. They cited a work by Itoh et al. who modified a proton exchange membrane electrolyzer with a Rh–Pt catalyst to generate hydrogen from water to hydrogenate benzene to cyclohexane in one

Exploring the role of halogen bonding in iodonium ylides: insights into unexpected reactivity and reaction control

• Carlee A. Montgomery and
• Graham K. Murphy

Beilstein J. Org. Chem. 2023, 19, 1171–1190, doi:10.3762/bjoc.19.86

• ]. They disclosed a reaction between acyclic iodonium ylides (e.g., 31/ I-10) and tertiary amines 32, which produced indoline rings 33 by forging two new C–C bonds between the ylidic carbon and unactivated positions on the amine (Scheme 5). In 2020, they disclosed a more complex variant of this reaction

• leading to malonate, the second equivalent of 31 coupled with the activated amine and cyclized to produce 33. The formation of 35 in their latter study was mechanistically analogous to this proposal; however, a third equivalent of ylide 31 was necessary to facilitate an additional series of PT and SET

• gave 33a in 32% yield, significantly lower than the previously obtained 56%, when the ortho-anisyl ylide 39 was used it gave 33a in a much improved 72% yield. The yields of other reactions that employed various amine and ylide derivatives were consistent with those previously obtained (Scheme 5

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

• ). Nucleophilic addition of the amine to the acyl radical and amine-assisted intermolecular proton transfer [84] generates the α-hydroxy radical 24 from which formation of the amide 25 proceeds either via i) oxidation by [Ir2]+ and deprotonation or ii) radical chain propagation [85]. Electron-deficient, electron

• . Notably, carbonylative amidation of a borylated aryl bromide to 26d proceeded well, where a Pd-catalyzed carbonylative amidation reaction would be plagued by undesired Suzuki coupling. Several secondary cyclic and acyclic amines, as well as primary amines were successfully employed as amine coupling

Copper-catalyzed N-arylation of amines with aryliodonium ylides in water

• Kasturi U. Nabar,
• Bhalchandra M. Bhanage and
• Sudam G. Dawande

Beilstein J. Org. Chem. 2023, 19, 1008–1014, doi:10.3762/bjoc.19.76

• amines smoothly proceeded N-arylation to give the corresponding tertiary amine derivatives with moderate yields after 6–8 hours. The results are summarised in Scheme 3. The reaction of N-methylaniline with iodonium ylide 2a in the presence of 10 mol % of catalyst delivered N-methyl-N-phenylaniline (3r

Aromatic C–H bond functionalization through organocatalyzed asymmetric intermolecular aza-Friedel–Crafts reaction: a recent update

• Anup Biswas

Beilstein J. Org. Chem. 2023, 19, 956–981, doi:10.3762/bjoc.19.72

• of indole 9 through aza-Friedel–Crafts reaction with aryl-α-ketimino esters 26/29. They also utilized unsubstituted and 2,3-disubstituted pyrroles 9 as π-nucleophile towards the same electrophiles to incorporate an amine-substituted quaternary stereocenter at the C2’ position (Scheme 8b) [33]. In

• stereocenter bearing primary amine and trifluoromethyl functionalities associated with appreciable enantiocontrol. The substrate scope was investigated by the variation of sterically and electronically divergent aryl substituents in the ketimines but the enantioselectivity was markedly lowered with sterically

• in 83 and the enantioregulation was achieved by BINOL-derived chiral phosphoric acid P22. An amine functionality was crucial in the isoxazole ring to enhance the nucleophilicity of the adjacent carbon atom. In addition, the amine hydrogen forms an H-bond with the catalyst along with another hydrogen

Clauson–Kaas pyrrole synthesis using diverse catalysts: a transition from conventional to greener approach

• Dileep Kumar Singh and
• Rajesh Kumar

Beilstein J. Org. Chem. 2023, 19, 928–955, doi:10.3762/bjoc.19.71

• proposed by Wang [55] (Scheme 2b), 2,5-dimethoxytetrahydrofuran (2) is first protonated with acetic acid, followed by ring opening to form carbocation B. In the following step, primary amine 1 nucleophilically attacks carbocation B to produce intermediate C, which, after proton rearrangement and the

• reactivity of the aromatic amine depends on the electron density of the amino compounds. In addition, the authors also performed the reaction of aliphatic amines with 2,5-DMTHF (2), and found that aliphatic amines are inert in the presence of MgI2 etherate. The proposed mechanism shown in Scheme 9b suggests

• and forms an unstable intermediate that easily forms activated dialdehyde B. The amine 24 reacts with activated dialdehyde and provides the corresponding pyrrole 25 through the removal of water molecules. Smith and co-workers [65] reported a modified one-pot, two-step Clauson–Kaas procedure for the

A fluorescent probe for detection of Hg²⁺ ions constructed by tetramethyl cucurbit[6]uril and 1,2-bis(4-pyridyl)ethene

• Xiaoqian Chen,
• Naqin Yang,
• Yue Ma,
• Xinan Yang and
• Peihua Ma

Beilstein J. Org. Chem. 2023, 19, 864–872, doi:10.3762/bjoc.19.63

• + ions [34]. Because of the synergistic combination of Q[8], SQ2 and Hg2+ ions, it shows fluorescence quenching. Cong's group found that Q[7] can encapsulate the benzimidazole part of N-(2-benzimidazolylmethyl)-N,N-bis(2-pyridylmethyl)amine cation (BIBPA+) to construct a host–guest fluorescent probe. The

Pyridine C(sp²)–H bond functionalization under transition-metal and rare earth metal catalysis

• Haritha Sindhe,
• Malladi Mounika Reddy,
• Karthikeyan Rajkumar,
• Akshay Kamble,
• Amardeep Singh,
• Anand Kumar and
• Satyasheel Sharma

Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62

• demonstrated that the reaction in the presence of cationic zirconium complexes derived from zirconium dibenzyl complexes bearing tridentate [ONO]-type amine-bridged bis(phenolato) ligands and [Ph3C][B(C6F5)4] (Scheme 5), gave rise to ortho-selective C–H alkylated pyridines 19 and 21. It was observed that the

• 205 were accessed in moderate to excellent yields and also naphthyridine derivatives (205k and 205l) were synthesized. In the proposed mechanism, the initial deprotonation of HNBn2 by Ln[N(TMS)2]3 provided the lanthanide amide. Activation of the vinyl-substituted pyridin-3-amine 204 by the lanthanide

Eschenmoser coupling reactions starting from primary thioamides. When do they work and when not?

• Lukáš Marek,
• Jiří Váňa,
• Jan Svoboda and
• Jiří Hanusek

Beilstein J. Org. Chem. 2023, 19, 808–819, doi:10.3762/bjoc.19.61

• MeCN undergoes a ring transformation [1][2] to give 2-phenyl-5-(2-aminophenyl)-4-hydroxy-1,3-thiazole (17') (Scheme 7) under kinetic control, the analogous intermediary hydroxythiazole 7a (Scheme 3) does not decompose into analogous thiazole 7a' due to much worse nucleofugality of the leaving amine

• elimination of the water molecule from 7a,b to give 8a,b to be preferred over the ring opening giving 7a,b'. The worse leaving ability of aliphatic amine nitrogen is also manifested in a much lower yield of thiazole 13 from salt 12b which preferably undergoes elimination, while salt 12a having a much better

• ). α-Bromophenylacetic acid amides (4a,b) were prepared from 2-bromo-2-phenylacetyl chloride [38] and the corresponding amine in DCM or toluene at reduced temperature (see Supporting Information File 1). Thiobenzamides and thiobenzanilides were prepared by magnesium chloride-catalyzed thiolysis of

Sulfate radical anion-induced benzylic oxidation of N-(arylsulfonyl)benzylamines to N-arylsulfonylimines

• Joydev K. Laha,
• Pankaj Gupta and
• Amitava Hazra

Beilstein J. Org. Chem. 2023, 19, 771–777, doi:10.3762/bjoc.19.57

• abstraction (HAT) followed by single electron transfer (SET) enabled by the sulfate radical anion (SO4·−). Results and Discussion Initially, we investigated the reaction of N-benzenesulfonyl(benzyl)amine (1a) as a model substrate with K2S2O8 in MeCN at 80 °C for 12 h, conditions that were used earlier in our

Synthesis of imidazo[1,2-a]pyridine-containing peptidomimetics by tandem of Groebke–Blackburn–Bienaymé and Ugi reactions

• Oleksandr V. Kolomiiets,
• Alexander V. Tsygankov,
• Maryna N. Kornet,
• Aleksander A. Brazhko,
• Vladimir I. Musatov and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2023, 19, 727–735, doi:10.3762/bjoc.19.53

• carbonyl component was proposed, but these aldehydes did not have the structure of imidazo[1,2-a]pyridine. Interestingly, in 2019 [1], the synthesis of the amine component using GBB-3CR and the modification of the imidazo-pyrimidine scaffold by a peptidomimetic chain was carried out using the Ugi reaction

• . Without isolation, the corresponding aldehyde, amine and isocyanide were added to the resulting iminopyridine product and the mixture was then stirred at room temperature for 12 h. But again, the expected compounds could not be obtained. Following this trend and based on published data, we synthesized

Palladium-catalyzed enantioselective three-component synthesis of α-arylglycine derivatives from glyoxylic acid, sulfonamides and aryltrifluoroborates

• Bastian Jakob,
• Nico Schneider,
• Luca Gengenbach and
• Georg Manolikakes

Beilstein J. Org. Chem. 2023, 19, 719–726, doi:10.3762/bjoc.19.52

• imine species provide a very flexible approach to the arylglycine scaffold [2][9]. The Petasis borono-Mannich reaction constitutes a prominent example for such an imine-based multicomponent reaction (Scheme 1a). The reaction of glyoxylic acid, an amine component and an arylboronic acid offers a highly

• electrophilic iminium carbon, leading to the amine product as racemic mixture. Consequently, examples for asymmetric Petasis borono-Mannich reactions are rare [13] and usually rely on the utilization of chiral amine components in stoichiometric amounts [10][11]. As part of our research program utilizing the in

Strategies in the synthesis of dibenzo[b,f]heteropines

• David I. H. Maier,
• Barend C. B. Bezuidenhoudt and
• Charlene Marais

Beilstein J. Org. Chem. 2023, 19, 700–718, doi:10.3762/bjoc.19.51

• of o-nitrotoluene (22) Reduction to 2,2'-diaminobibenzyl (20) Ring-closing via amine condensation Catalytic dehydrogenation 1.1 Oxidative coupling of o-nitrotoluene (22) and reduction to 2,2'-diaminobibenzyl (20) The preparation of dinitrobibenzyl (21) can be achieved by the oxidative coupling of

• transition metal (Ni, Fe, V) porphyrin catalysts and oxygen. Catalytic reduction (H2, Pd/C) affords 2,2'-diaminobibenzyl (20) in the subsequent step [28]. 1.2 Ring-closing via amine condensation The initial synthesis of 10,11-dihydro-5H-dibenzo[b,f]azepine (2a) was reported in 1899 by Thiele and Holzinger

• '-dibromostilbenes 61 by means of a double Buchwald–Hartwig amination gave yields between 62% and 96% using aniline as the amine reactant (Scheme 13). The reaction proved to be compatible with both aromatic and aliphatic amines and the reaction time varied between 11 and 24 hours. Fluoro, chloro, nitrile, alkyl, and

Nucleophile-induced ring contraction in pyrrolo[2,1-c][1,4]benzothiazines: access to pyrrolo[2,1-b][1,3]benzothiazoles

• Ekaterina A. Lystsova,
• Maksim V. Dmitriev,
• Andrey N. Maslivets and
• Ekaterina E. Khramtsova

Beilstein J. Org. Chem. 2023, 19, 646–657, doi:10.3762/bjoc.19.46

• due to the solubility of the starting amine 11d and the corresponding products 12. In addition, in the reaction of APBTT 1a with mesidine (11b), we succeeded to isolate a side-product 14ab (Scheme 19). Similar side-products 14 were observed in all reactions of APBTTs 1 with arylamines 11 (UPLC–UV–MS

• nucleophilicity of the amine. Then, we examined the proposed approach to PBTAs by involving bulky nucleophilic compounds 16a–d to the reaction with APBTT 1a. Unexpectedly, product 17a was formed instead of the anticipated PBTA C (Scheme 20). Compound 17a was formed in good isolated yields (60–70%) and was

Enolates ambushed – asymmetric tandem conjugate addition and subsequent enolate trapping with conventional and less traditional electrophiles

• Péter Kisszékelyi and
• Radovan Šebesta

Beilstein J. Org. Chem. 2023, 19, 593–634, doi:10.3762/bjoc.19.44

• secondary amine 157 generated in the cyclization step (Scheme 40B). Consequently, the complex tetracyclic compound 158 was produced in 47% yield and with good stereoselectivity (84% ee, dr 7.5:1). At about the same time, comparable results were reported by the group of Zhang [82]. Their Cu-catalyzed cascade

C3-Alkylation of furfural derivatives by continuous flow homogeneous catalysis

• Grédy Kiala Kinkutu,
• Catherine Louis,
• Myriam Roy,
• Juliette Blanchard and
• Julie Oble

Beilstein J. Org. Chem. 2023, 19, 582–592, doi:10.3762/bjoc.19.43

• -situ imine formation is currently impossible with catalytic or stoichiometric amounts of amine due to decarbonylation of furfural under the reaction conditions [21]. We thus present here an adaptation of our Ru(0)-catalyzed C3-alkylation strategy of furfural derivatives to a continuous flow system

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

• (5). This compound was synthesized smoothly within three steps in 16.6% overall yield. The synthetic route commenced from the preparation of N-protected amine 3, followed by the deprotection of benzylamine 3 to furnish 4 and ended with the diazotization of 4 using tert-butyl nitrite. As a result, the

Transition-metal-catalyzed domino reactions of strained bicyclic alkenes

• Austin Pounder,
• Eric Neufeld,
• Peter Myler and
• William Tam

Beilstein J. Org. Chem. 2023, 19, 487–540, doi:10.3762/bjoc.19.38

• lab reported the Rh-catalyzed domino reaction of doubly bridgehead-substituted oxabicyclic alkenes 134 with secondary amine nucleophiles 135 for the synthesis of bicyclo[2.2.2]lactones 136 (Scheme 24) [70]. This reaction proceeded smoothly with a variety of secondary amine nucleophiles, including

• undergo the domino reaction, generating the desired bicyclo[2.2.2]lactone 136. The authors proposed the reaction first takes place through an ARO of the doubly bridgehead-substituted oxabicyclic alkene with the secondary amine nucleophile ultimately producing 137. The Rh(I) catalyst then facilitates the

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

• Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

• -linked porphyrin-fullerene dyads 100a–d and 104a,b. Firstly, meso-triazole-linked porphyrin conjugates 99a–d and 103a,b were synthesized from porphyrins 97a,b and 101, as shown in Scheme 20. For the click reaction between porphyrin 101 and alkyne 102a,b, one equivalent of tris(benzotriazolylmethyl)amine

• (TBTA) was also added as an additive to increase the yield of triazoloporphyrins 103a,b. When TBTA, a tertiary amine with a 1,2,3-triazole ring, is added to a Cu-catalyzed click reaction, it forms a complex to stabilize the Cu(I) oxidation state and speeds up the reaction. Further, these 1,2,3-triazole

• 124 in the presence of copper bromide and tris((1-benzyl-4-triazolyl)methyl)amine (TBTA) in DMSO/H2O to give a porphyrin-lantern (PL)-DNA sequence in 45% yield after cleavage and deprotection. These PL-DNA sequences were further used to construct strong and fluorescent G-wires that could be useful for