Transition-metal-free synthesis of 3-sulfenylated chromones via KIO₃-catalyzed radical C(sp²)–H sulfenylation

• Yanhui Guo,
• Shanshan Zhong,
• Li Wei and
• Jie-Ping Wan

Beilstein J. Org. Chem. 2017, 13, 2017–2022, doi:10.3762/bjoc.13.199

• (reaction 1, Scheme 3). In addition, sulfonyl hydrazine 2b gave disulfide 6 under the same conditions (reaction 2, Scheme 3), suggesting that chromone 5 and disulfide 6 might be key intermediates in the domino reactions. Moreover, the same reaction in the presence of TEMPO gave no formation of 6, indicating

N-Propargylamines: versatile building blocks in the construction of thiazole cores

• S. Arshadi,
• E. Vessally,
• L. Edjlali,
• R. Hosseinzadeh-Khanmiri and
• E. Ghorbani-Kalhor

Beilstein J. Org. Chem. 2017, 13, 625–638, doi:10.3762/bjoc.13.61

• domino reactions of N-propargylamines 20 with isothiocyanates 21 developed by Castagnolo. Electrophile-mediated cyclization of N-propargylthioureas 55.

Synthesis of structurally diverse 3,4-dihydropyrimidin-2(1H)-ones via sequential Biginelli and Passerini reactions

• Andreas C. Boukis,
• Baptiste Monney and
• Michael A. R. Meier

Beilstein J. Org. Chem. 2017, 13, 54–62, doi:10.3762/bjoc.13.7

• the Passerini α-acyloxycarboxamide adduct 12 [18]. Tandem reactions Tandem reactions (also known as cascade [22] or domino reactions [23]) are chemical transformations that involve at least two independent reactions utilizing different functional groups with distinct chemical reactivities [24][25][26

Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

• Mohammad Haji

Beilstein J. Org. Chem. 2016, 12, 1269–1301, doi:10.3762/bjoc.12.121

• , carbamate 138, hexahydrobenzothiophene 140 and benzothiophene 142 were converted to the corresponding bisphosphonates 139, 141 and 143, respectively (Scheme 30). The synthesized heterocyclic bisphosphonates showed anti-inflammatory properties. 3 Knoevenagel-induced domino reactions An efficient method into

Synthesis of β-arylated alkylamides via Pd-catalyzed one-pot installation of a directing group and C(sp³)–H arylation

• Yunyun Liu,
• Yi Zhang,
• Xiaoji Cao and
• Jie-Ping Wan

Beilstein J. Org. Chem. 2016, 12, 1122–1126, doi:10.3762/bjoc.12.108

• known syntheses, a domino process by which the AQ can be linked directly to the raw substrates to enable the subsequent arylation transformation in one pot would be highly favorable for enhancing step economy. Upon this assumption as well as our interest in both domino reactions and C–H

Cupreines and cupreidines: an established class of bifunctional cinchona organocatalysts

• Laura A. Bryant,
• Rossana Fanelli and
• Alexander J. A. Cobb

Beilstein J. Org. Chem. 2016, 12, 429–443, doi:10.3762/bjoc.12.46

• review are already domino reactions (e.g., MBH, and the cyclopropanation), a recent and clearer example of the use of a 6’-OH cinchona derived catalyst in such a process comes from the laboratory of Samanta and co-workers [67][68]. They have demonstrated an enantioselective domino reaction between 3

A quadruple cascade protocol for the one-pot synthesis of fully-substituted hexahydroisoindolinones from simple substrates

• Hong-Bo Zhang,
• Yong-Chun Luo,
• Xiu-Qin Hu,
• Yong-Min Liang and
• Peng-Fei Xu

Beilstein J. Org. Chem. 2016, 12, 253–259, doi:10.3762/bjoc.12.27

• . Previously, we established organocatalytic domino reactions to construct very useful molecular architectures [47][48][49][50][51][52][53][54][55][56][57][58][59][60]. Based on this past experience, we decided to develop a one-pot quadruple protocol to construct this difficult molecular architecture using

An efficient synthesis of N-substituted 3-nitrothiophen-2-amines

• Sundaravel Vivek Kumar,
• Shanmugam Muthusubramanian,
• J. Carlos Menéndez and
• Subbu Perumal

Beilstein J. Org. Chem. 2015, 11, 1707–1712, doi:10.3762/bjoc.11.185

• goals of green chemistry [32]. In this context, we wish to report herein a new and efficient synthesis of 3-nitro-N-aryl/alkylthiophen-2-amines based on domino reactions between α-nitroketene N,S-aryl/alkylaminoacetals and 1,4-dithiane-2,5-diol, the dimer of 2-mercaptoacetaldehyde (Scheme 2). This work

Multicomponent versus domino reactions: One-pot free-radical synthesis of β-amino-ethers and β-amino-alcohols

• Bianca Rossi,
• Nadia Pastori,
• Simona Prosperini and
• Carlo Punta

Beilstein J. Org. Chem. 2015, 11, 66–73, doi:10.3762/bjoc.11.10

One-pot four-component reaction for convenient synthesis of functionalized 1-benzamidospiro[indoline-3,4'-pyridines]

• Chao Wang,
• Yan-Hong Jiang and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2014, 10, 2671–2676, doi:10.3762/bjoc.10.281

• generation of Huisgen’s 1,4-dipoles are aromatic heterocycles such as N-alkylimidazole, pyridine, quinoline, isoquinoline and primary aromatic amines. In recent years, other nitrogen-containing nucleophiles such as hydrazine and arylhydrazines are also used to generate Huisgen’s 1,4-dipoles in domino

• reactions [19][20][21]. Recently, we and Perumal have demonstrated that the four-component reaction of arylamine, acetylenedicarboxylate, isatin and malononitrile can afford the spiro[indoline-3,4’-pyridine] derivatives in satisfactory yields [22][23][24]. We envisioned that functionalized spiro[indoline

A simple copper-catalyzed two-step one-pot synthesis of indolo[1,2-a]quinazoline

• Chunpu Li,
• Lei Zhang,
• Shuangjie Shu and
• Hong Liu

Beilstein J. Org. Chem. 2014, 10, 2441–2447, doi:10.3762/bjoc.10.254

• aryl halides with active methylene compounds such as ethyl acetoacetate, malononitrile, cyanoacetate and their equivalents [8][9][10][11][12][13][14][15]. Copper-catalyzed domino reactions have also been used in the synthesis of nitrogen-containing compounds [16][17][18][19][20]. Ma et al reported a

Chiral phosphines in nucleophilic organocatalysis

• Yumei Xiao,
• Zhanhu Sun,
• Hongchao Guo and
• Ohyun Kwon

Beilstein J. Org. Chem. 2014, 10, 2089–2121, doi:10.3762/bjoc.10.218

• organocatalytic asymmetric domino reactions allow the rapid construction of structurally complex molecules from readily available starting materials in two or more steps in a single operation, they have attracted much attention. Bifunctional chiral phosphines are ideal chiral catalysts for tandem reactions. In

Multicomponent reactions in nucleoside chemistry

• Mariola Koszytkowska-Stawińska and
• Włodzimierz Buchowicz

Beilstein J. Org. Chem. 2014, 10, 1706–1732, doi:10.3762/bjoc.10.179

• considerable number of pacidamycin analogues. 4. The multicomponent domino reactions initiated by the Knoevenagel condensation The Knoevenagel condensation can be considered as one of the most useful tools for the formation of C=C double bonds. The condensation products, i.e., electron-deficient alkenes

• , readily act in subsequent reactions as Michael acceptors, Diels–Alder (hetero)dienes or dienophiles, or dipolarophiles. Multicomponent domino reactions initiated by the Knoevenagel condensation are a valuable tool for the construction of many compounds with complex molecular structures [90]. The syntheses

• shown in Scheme 23 and Scheme 24 represent examples of the Knoevenagel condensation-initiated domino reactions where the nucleoside aldehyde (i.e., 5-formyl-3',5'-di-O-acetyl-2'-deoxyuridine (14) or 5-formyl-2'-deoxyuridine (27)) acted as the Knoevenagel acceptor. Compounds 61 to 65 were prepared by the

The Ugi four-component reaction as a concise modular synthetic tool for photo-induced electron transfer donor-anthraquinone dyads

• Sarah Bay,
• Gamall Makhloufi,
• Christoph Janiak and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2014, 10, 1006–1016, doi:10.3762/bjoc.10.100

• diversity-oriented syntheses of chromophores [62][63][64][65][66][67][68][69] we have established accesses to chromophores in a one-pot fashion based upon transition metal catalysis as an entry to consecutive multicomponent [70][71] and domino reactions [72]. The highly convergent synthetic approach by

Domino reactions of 2H-azirines with acylketenes from furan-2,3-diones: Competition between the formation of ortho-fused and bridged heterocyclic systems

• Alexander F. Khlebnikov,
• Mikhail S. Novikov,
• Viktoriia V. Pakalnis,
• Roman O. Iakovenko and
• Dmitry S. Yufit

Beilstein J. Org. Chem. 2014, 10, 784–793, doi:10.3762/bjoc.10.74

One-pot three-component synthesis and photophysical characteristics of novel triene merocyanines

• Christian Muschelknautz,
• Robin Visse,
• Jan Nordmann and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2014, 10, 599–612, doi:10.3762/bjoc.10.51

• , and photophysics. Inspired by the concept of a diversity-oriented synthetic approach to chromophores [19][20][21][22][23][24][25][26] we have launched a program to apply transition metal-catalyzed processes as an entry to consecutive multicomponent [27][28] and domino reactions [29]. These highly

Silver and gold-catalyzed multicomponent reactions

• Giorgio Abbiati and
• Elisabetta Rossi

Beilstein J. Org. Chem. 2014, 10, 481–513, doi:10.3762/bjoc.10.46

A catalyst-free multicomponent domino sequence for the diastereoselective synthesis of (E)-3-[2-arylcarbonyl-3-(arylamino)allyl]chromen-4-ones

• Pitchaimani Prasanna,
• Pethaiah Gunasekaran,
• Subbu Perumal and
• J. Carlos Menéndez

Beilstein J. Org. Chem. 2014, 10, 459–465, doi:10.3762/bjoc.10.43

• Madrid, Spain 10.3762/bjoc.10.43 Abstract The three-component domino reactions of (E)-3-(dimethylamino)-1-arylprop-2-en-1-ones, 3-formylchromone and anilines under catalyst-free conditions afforded a library of novel (E)-3-(2-arylcarbonyl-3-(arylamino)allyl)-4H-chromen-4-ones in good to excellent yields

• –Hilman condensation, and a final deoxygenation. The deoxygenation is assumed to be induced by carbon monoxide resulting from the thermal decomposition of the dimethylformamide solvent. Keywords: chromones; domino reactions; Michael additions; multicomponent reactions; transfer hydrogenation

Recent applications of the divinylcyclopropane–cycloheptadiene rearrangement in organic synthesis

• Sebastian Krüger and
• Tanja Gaich

Beilstein J. Org. Chem. 2014, 10, 163–193, doi:10.3762/bjoc.10.14

• overview of the new mechanistic insights concerning the title reaction is provided as well as a condensed account on the biological relevance of the topic. Heteroatom variants of this rearrangement are covered briefly. Keywords: cycloheptadiene; divinylcyclopropane rearrangement; domino reactions; natural

Four-component reaction of cyclic amines, 2-aminobenzothiazole, aromatic aldehydes and acetylenedicarboxylate

• Hong Gao,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2013, 9, 2934–2939, doi:10.3762/bjoc.9.330

• nitrogen-containing heterocycles [11][12][13][14][15][16]. In this hot research field, we also successfully developed a series of domino reactions containing primary amine, electron-deficient alkynes and the other components, and found several efficient synthetic protocols for versatile heterocycles and

• -dipoles very fast and in nearly quantitative yields [25][26]. But until now it seems that this kind of easily generated Huisgen 1,4-dipoles have not been utilized for the design of domino reactions. In continuation of our efforts to explore the practical applications of Huisgen 1,4-dipoles for the

• sequentially with other reagents to give cycloaddition products [1][2]. From then on much developments on the chemistry of Huisgen 1,4-dipoles have been achieved [3][4]. In the past few years, Huisgen 1,4-dipoles have been recognized as key components for designing practical multicomponent reactions and domino

Catalytic asymmetric tandem Friedel–Crafts alkylation/Michael addition reaction for the synthesis of highly functionalized chromans

• Jiahuan Peng and
• Da-Ming Du

Beilstein J. Org. Chem. 2013, 9, 1210–1216, doi:10.3762/bjoc.9.137

• stereogenic centers [1][2][3][4][5][6][7][8][9][10][11][12][13]. Newly developed tandem/domino reactions are increasingly applied in the synthesis of natural products and other biologically active compounds [14][15][16]. Dihydrocoumarins, chromans, and chromenes can be found in many natural products and

Synthesis of functionalized spiro[indoline-3,4’-pyridines] and spiro[indoline-3,4’-pyridinones] via one-pot four-component reactions

• Li-Juan Zhang,
• Qun Wu,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2013, 9, 846–851, doi:10.3762/bjoc.9.97

• of a wide variety of heterocycles and pharmaceutical compounds [6][7][8][9][10][11]. Many domino reactions have been developed by trapping this kind of β-enamino ester with sequential adding of nucleophilic or electrophilic reagents to give versatile nitrogen-containing compounds and N,O-heterocycles

• [12][13][14][15][16][17][18][19][20][21][22][23]. Recently, Perumal and we have both developed an efficient synthetic procedure for functionalized spiro[indoline-3,4’-pyridines] by domino reactions of in situ generated β-enamino esters, isatin and malononitrile with triethylamine as the base catalyst

• [indoline-3,4’-pyridinones] 3. Benzylamine and 2-phenylethylamine could also be used in the domino reactions to give the spiro[indoline-3,4’-pyridinones] 3k–3n as the main products (Table 2, entries 19–22). The structures of the prepared spiro compounds 2a–2h and 3a–3n were fully established by

Diastereoselective synthesis of nitroso acetals from (S,E)-γ-aminated nitroalkenes via multicomponent [4 + 2]/[3 + 2] cycloadditions promoted by LiCl or LiClO₄

• Leandro Lara de Carvalho,
• Robert Alan Burrow and
• Vera Lúcia Patrocinio Pereira

Beilstein J. Org. Chem. 2013, 9, 838–845, doi:10.3762/bjoc.9.96

• Domingos and co-workers in a PM3 study on domino reactions with nitroalkenes [34]. Additionally, it is possible that the high internal pressure of the solvent acts synergistically to promote the enhancement of the reaction rate of 5a–c and should not be neglected. In all cycloadditions, independent of the

Facile synthesis of functionalized tetrahydroquinolines via domino Povarov reactions of arylamines, methyl propiolate and aromatic aldehydes

• Jing Sun,
• Hong Gao,
• Qun Wu and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2012, 8, 1839–1843, doi:10.3762/bjoc.8.211

• electron-deficient alkynes, such as methyl propiolate or dimethyl acetylenedicarboxylate [27][28][29][30], have shown versatile reactivity and have been widely used as key intermediates in a number of domino reactions to construct heterocyclic systems [31][32][33][34][35][36][37][38][39][40][41][42

Palladium-catalyzed dual C–H or N–H functionalization of unfunctionalized indole derivatives with alkenes and arenes

• Gianluigi Broggini,
• Egle M. Beccalli,
• Andrea Fasana and
• Silvia Gazzola

Beilstein J. Org. Chem. 2012, 8, 1730–1746, doi:10.3762/bjoc.8.198

• requires an oxidation by the copper(II) salt to the Pd(II) species, which is then suitable to restart a new catalytic cycle. Recently, the oxidative Pd(II)-catalyzed strategy for the cyclization of alkenylindoles has been extended to the intramolecular domino reactions of indolylallylamides by using the

• /carboxylation reaction. Plausible catalytic cycle for the cyclization/carboxylation of alkenylindoles, adapted from Liu et al. [81]. Intramolecular domino reactions of indolylallylamides through alkenylation/halogenation or alkenylation/esterification processes. Proposed mechanism for the alkenylation

• /esterification process through iminium intermediates. Cyclization of 3-indolylallylcarboxamides involving 1,2-migration of the acyl group from spiro-intermediates. Domino reactions of 2-indolylallylcarboxamides involving N–H functionalization. Cyclization/acyloxylation reaction of 3-alkenylindoles. Doubly