One-pot functionalisation of N-substituted tetrahydroisoquinolines by photooxidation and tunable organometallic trapping of iminium intermediates

• Joshua P. Barham,
• Matthew P. John and
• John A. Murphy

Beilstein J. Org. Chem. 2014, 10, 2981–2988, doi:10.3762/bjoc.10.316

• construct THIQs using green technologies, in mild conditions and with high atom efficiencies. Catalytic oxidative functionalisation of the C–H bond α- to the amine function is one such methodology. Iminium salts generated in this way can be intercepted by a nucleophile in a one-pot reaction (Scheme 1

Solution processable diketopyrrolopyrrole (DPP) cored small molecules with BODIPY end groups as novel donors for organic solar cells

• Diego Cortizo-Lacalle,
• Calvyn T. Howells,
• Upendra K. Pandey,
• Joseph Cameron,
• Neil J. Findlay,
• Anto Regis Inigo,
• Tell Tuttle,
• Peter J. Skabara and
• Ifor D. W. Samuel

Beilstein J. Org. Chem. 2014, 10, 2683–2695, doi:10.3762/bjoc.10.283

• one-pot reaction. Extending the conjugated π-system of a compound leads to a narrower HOMO–LUMO gap and a bathochromic shift of the absorption spectrum. Both effects are usually desirable to enhance the solar absorption. Therefore, an extended analogue of compound 6 with an additional thiophene ring

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

• ; multicomponent reaction; one-pot reaction; spiro[indoline-3,4'-pyridine]; Introduction The spirooxindole system is the core structure of many natural products and pharmaceutically important structures with notable structural complexity and biological activities of great interest [1][2][3][4]. Accordingly, many

(CF₃CO)₂O/CF₃SO₃H-mediated synthesis of 1,3-diketones from carboxylic acids and aromatic ketones

• JungKeun Kim,
• Elvira Shokova,
• Victor Tafeenko and
• Vladimir Kovalev

Beilstein J. Org. Chem. 2014, 10, 2270–2278, doi:10.3762/bjoc.10.236

• recently reported by us [27] and decarboxylation was subsequently carried out, 1,3-diphenylphosphorylated acetone 5 could be obtained (reaction 2 in Scheme 2). The two-stage one-pot reaction of γ-phenylbutanoic acid (1c) and 3-hydroxy-1-adamantylacetic acid (1k) gave as a result the trifluoroacetylated

Synthesis of phosphoramidites of isoGNA, an isomer of glycerol nucleic acid

• Keunsoo Kim,
• Venkateshwarlu Punna,
• Phaneendrasai Karri and
• Ramanarayanan Krishnamurthy

Beilstein J. Org. Chem. 2014, 10, 2131–2138, doi:10.3762/bjoc.10.220

• N6-benzoyladenine reaction). Initially, we tried to simultaneously deprotect both Boc groups and the TBDPS group in the presence of TBAF in a one-pot reaction [29]. However, only the TBDPS group was removed and a quantitative amount of mono-protected compound 30 was produced (Scheme 6). The fluoride

One-pot stereoselective synthesis of α,β-differentiated diamino esters via the sequence of aminochlorination, aziridination and intermolecular S_N2 reaction

• Yiwen Xiong,
• Ping Qian,
• Chenhui Cao,
• Haibo Mei,
• Jianlin Han,
• Guigen Li and
• Yi Pan

Beilstein J. Org. Chem. 2014, 10, 1802–1807, doi:10.3762/bjoc.10.189

• . Herein, we report an anomalous outcome in the one-pot reaction, which provides a highly efficient method for the synthesis of α,β-differentiated diamino esters directly from readily available starting materials, α,β-unsaturated ester, N,N-dichlorotoluenesulfonamide (TsNCl2) and benzylamine. Furthermore

• benzylamine under similar reaction conditions of the third step of this one-pot reaction (Scheme 3). To our delight, aziridine 6 was converted into the corresponding diamino acid ester 5b with 73% chemical yield. Thus, aziridine most likely might be the intermediate in this reaction. Based on the above

• results, a proposed reaction mechanism for this one-pot reaction is illustrated in Scheme 4, which contains the sequence of aminochlorination, aziridination and followed by the SN2 nucleophilic ring-opening. The first step is the Cu-catalyzed aminochlorination reaction of methyl cinnamate 1a resulting in

Design and synthesis of multivalent neoglycoconjugates by click conjugations

• Feiqing Ding,
• Li Ji,
• Ronny William,
• Hua Chai and
• Xue-Wei Liu

Beilstein J. Org. Chem. 2014, 10, 1325–1332, doi:10.3762/bjoc.10.134

• -allohexopyranoside (2a) in gram scale via BF3∙OEt2-promoted one-pot three-component α-selective tandem hydroamination/glycosylation reaction (Scheme 1). In fact, when 3,4,6-tri-O-acetyl-D-glucal (1a), propargyl alcohol and p-toluenesulfonamide were subjected to a one-pot reaction in the presence of 2.2 equiv of BF3

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

• spectroscopy [56]. The donor-only (2) and acceptor-only (3) models for spectroscopic comparison were obtained analogously. For enabling rapid accesses to functional π-systems, such as Do–Acc dyads for photo-induced charge separation, besides a robust, flexible diversity-oriented one-pot reaction, such as the

Allenylphosphine oxides as simple scaffolds for phosphinoylindoles and phosphinoylisocoumarins

• G. Gangadhararao,
• Ramesh Kotikalapudi,
• M. Nagarjuna Reddy and
• K. C. Kumara Swamy

Beilstein J. Org. Chem. 2014, 10, 996–1005, doi:10.3762/bjoc.10.99

• the nitrogen lone pair on the β-carbon [24] of the allene forming addition product II or III. This upon treating with aq NaOH leads to the deacylated/debenzoylated phosphinoylindoles. In the one-pot reaction, though, the in situ generated allenylphosphine oxide first undergoes deacylation

Convergent synthesis of a tetrasaccharide repeating unit of the O-specific polysaccharide from the cell wall lipopolysaccharide of Azospirillum brasilense strain Sp7

• Pintu Kumar Mandal,
• Debashis Dhara and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2014, 10, 293–299, doi:10.3762/bjoc.10.26

• 1. A number of suitably functionalized monosaccharide intermediates 2, 3 [30], 4 [31], and 5 [32] were prepared from the reducing sugars by using literature reports. The application of a one-pot reaction sequence for the stereoselective glycosylation and the removal of the p-methoxybenzyl (PMB

• “armed–disarmed” effect as well as the removal of PMB ether in a one-pot reaction following the glycosylation reduced the overall number of steps. Experimental General methods All reactions were monitored by thin-layer chromatography over silica gel-coated TLC plates. TLC spots were visualized by warming

Substrate dependent reaction channels of the Wolff–Kishner reduction reaction: A theoretical study

• Shinichi Yamabe,
• Guixiang Zeng,
• Wei Guan and
• Shigeyoshi Sakaki

Beilstein J. Org. Chem. 2014, 10, 259–270, doi:10.3762/bjoc.10.21

• convenient method of the W-K reduction [4][5]. The method involves heating R1(R2)C=O, KOH and hydrazine hydrate (H2N–NH2·H2O) together in diethylene glycol (DEG in Scheme 1). This method gives the products from steroid ketones in a one-pot reaction and with a high yield. Scheme 2 shows the reaction mechanism

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

• generated using a one-pot reaction involving condensation of ethyl propiolate (4a) with benzylidenemalononitrile (7a) in the presence of L-proline (5) (Scheme 4) [4]. It is believed that the pathway followed in this process involves conjugate addition of proline to the propiolate to yield adduct 6 which

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

• functionalized 2-pyrrolidinon-3-olates 2a–2h as a one-pot reaction: A mixture of 2-aminobenzothiazole (2.0 mmol), acetylenedicarboxylate (2.0 mmol), aromatic aldehyde (2.0 mmol), morpholine or piperidine (3.0 mmol) and p-toluenesulfonic acid (0.5 mmol) in ethanol (10.0 mL) was stirred at room temperature for

One-pot cross-enyne metathesis (CEYM)–Diels–Alder reaction of gem-difluoropropargylic alkynes

• Santos Fustero,
• Paula Bello,
• Javier Miró,
• María Sánchez-Roselló,
• Günter Haufe and
• Carlos del Pozo

Beilstein J. Org. Chem. 2013, 9, 2688–2695, doi:10.3762/bjoc.9.305

• group, which involved the use of 1,7-octadiene as an internal source of ethylene. Keywords: cross metathesis; Diels–Alder; one-pot reaction; organo-fluorine; propargylic difluorides; Introduction In recent years the number of applications of olefin metathesis as a mild and competitive synthetic method

One-pot sequential synthesis of isocyanates and urea derivatives via a microwave-assisted Staudinger–aza-Wittig reaction

• Diego Carnaroglio,
• Katia Martina,
• Giovanni Palmisano,
• Andrea Penoni,
• Claudia Domini and
• Giancarlo Cravotto

Beilstein J. Org. Chem. 2013, 9, 2378–2386, doi:10.3762/bjoc.9.274

• : isocyanates; microwave-assisted reaction; one-pot reaction; tandem Staudinger–aza-Wittig reaction; urea derivatives; Introduction The industrial and commercial impact of isocyanates (R–NCO) is steadily growing. In particular, the polyurethane output has undergone yearly increases of 5% over the last decade

Silica sulfuric acid: a reusable solid catalyst for one pot synthesis of densely substituted pyrrole-fused isocoumarins under solvent-free conditions

• Sudipta Pathak,
• Kamalesh Debnath and
• Animesh Pramanik

Beilstein J. Org. Chem. 2013, 9, 2344–2353, doi:10.3762/bjoc.9.269

• ninhydrin to form Schiff bases. To overcome the above problems we have designed an operationally simple one-pot reaction for the synthesis of pyrrole-fused isocoumarins (5 or 8) from the ninhydrin adducts of acetylacetone/ethyl acetoacetate (6 or 7) [43] and primary amines 2 under solvent-free conditions

AgOTf-catalyzed one-pot reactions of 2-alkynylbenzaldoximes with α,β-unsaturated carbonyl compounds

• Qiuping Ding,
• Dan Wang,
• Puying Luo,
• Meiling Liu,
• Shouzhi Pu and
• Liyun Zhou

Beilstein J. Org. Chem. 2013, 9, 1949–1956, doi:10.3762/bjoc.9.231

• single operation, play an important role in atom-economical organic chemistry. A cascade reaction is the most efficient way for targeting fine chemicals, agrochemicals, pharmaceutical drugs, drug intermediates and ingredients by a one-pot reaction in environmentally and economically friendly synthetic

• regioselective alkylation of isoquinoline N-oxide and its derivatives with sulfoxides for the synthesis of 1-alkylated isoquinolines [40]. We also reported the synthesis of 1-arylated 1,3-disubstituted isoquinoline N-oxides in a one-pot reaction characterized by a Ag-catalyzed intramolecular addition cyclization

• -alkenylated isoquinoline 4 was synthesized via a Pd-mediated C–H bond activation approach in a one-pot reaction. The intermediate isoquinoline N-oxide A was produced in situ from 2-alkynylbenzaldoximes and reacted with the α,β-unsaturated carbonyl compound 2e to yield 1-alkenylated isoquinoline 4 (Scheme 3

Synthesis of enones, pyrazolines and pyrrolines with gem-difluoroalkyl side chains

• Assaad Nasr El Dine,
• Ali Khalaf,
• Danielle Grée,
• Olivier Tasseau,
• Fares Fares,
• Nada Jaber,
• Philippe Lesot,
• Ali Hachem and
• René Grée

Beilstein J. Org. Chem. 2013, 9, 1943–1948, doi:10.3762/bjoc.9.230

•  3). It appeared that the reaction conditions for the synthesis of these pyrazolines were compatible with the first isomerisation step, therefore the possibility of a "one-pot" reaction was considered. Indeed, by heating a mixture of propargylic alcohols 2a–2e with DBU (1,8-diazabicycloundec-7-ene

• ) in the presence of methylhydrazine (Scheme 4) the pyrazolines 4a–4e were obtained after 3–7 h in excellent yields (82–92%, Table 2). This very short and efficient synthesis of pyrazolines 4 can be related to another excellent one-pot reaction with 3-components where the first step is a Pd-catalyzed

• Supporting Information File 1 for details). The reaction conditions were compatible with both steps and an example of a one-pot reaction was performed starting from 2a–2e. The desired pyrrolines 6a–6e were obtained in excellent yields (71–76%, Scheme 6 and Table 3). Another important issue was the

Straightforward synthesis of a tetrasaccharide repeating unit corresponding to the O-antigen of Escherichia coli O16

• Manas Jana and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2013, 9, 1757–1762, doi:10.3762/bjoc.9.203

• stereoselective glycosylation of compounds 2 and 3 in the presence of a combination of N-iodosuccinimide (NIS) and triflic acid (TfOH) [18][19], followed by the removal of the p-methoxybenzyl (PMB) group in a one-pot reaction [17] by tuning the reaction conditions furnished the disaccharide acceptor 6 in 76

Appel-reagent-mediated transformation of glycosyl hemiacetal derivatives into thioglycosides and glycosyl thiols

• Tamashree Ghosh,
• Abhishek Santra and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2013, 9, 974–982, doi:10.3762/bjoc.9.112

• carbonotrithioate (derived from the reaction of CS2 and Na2S·9H2O) furnished thioglycosides and glycosyl thiols in excellent yield with high stereoselectivity in a two-step, one-pot reaction condition. The reaction condition is operationally simple, mild, reproducible, high-yielding, highly stereoselective, and can

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

• arylamines and other primary amines. Keywords: 1,4-dihydropyridine; electron-deficient alkyne; four-component reaction; isatin; one-pot reaction; spiro compound; Introduction β-Enaminones and β-enamino esters represent important synthetic building blocks for the development of versatile carbon–carbon bond

A facile, rapid, one-pot regio/stereoselective synthesis of 2-iminothiazolidin-4-ones under solvent/scavenger-free conditions

• Murugan Sathishkumar,
• Sangaraiah Nagarajan,
• Poovan Shanmugavelan,
• Murugan Dinesh and
• Alagusundaram Ponnuswamy

Beilstein J. Org. Chem. 2013, 9, 689–697, doi:10.3762/bjoc.9.78

• are presented below. Results and Discussion At the outset, optimization of the one-pot reaction was attempted by varying the solvents and using triethylamine as the acid scavenger (Table 1). The reaction was also attempted under solvent-free conditions. The latter was more promising in the sense that

1-n-Butyl-3-methylimidazolium-2-carboxylate: a versatile precatalyst for the ring-opening polymerization of ε-caprolactone and rac-lactide under solvent-free conditions

• Astrid Hoppe,
• Faten Sadaka,
• Claire-Hélène Brachais,
• Gilles Boni,
• Jean-Pierre Couvercelle and
• Laurent Plasseraud

Beilstein J. Org. Chem. 2013, 9, 647–654, doi:10.3762/bjoc.9.73

• . In this quest and encouraged by our previous results, we chose to explore the potential of zwitterionic 1-n-butyl-3-methylimidazolium-2-carboxylate (BMIM-2-CO2, Figure 1). Indeed, methylimidazolium-2-carboxylates can be easily synthesized with high yields by the one-pot reaction of dimethyl carbonate

Reactions of salicylaldehyde and enolates or their equivalents: versatile synthetic routes to chromane derivatives

• Ishmael B. Masesane and
• Zelalem Yibralign Desta

Beilstein J. Org. Chem. 2012, 8, 2166–2175, doi:10.3762/bjoc.8.244

• used. Chromane derivatives from the reactions of salicylaldehyde and enolate equivalents derived from malononitrile and its derivatives The one-pot reaction of salicylaldehyde and malononitrile has proved to be an efficient method for the synthesis of 2-iminochromene derivatives. In general such

An efficient access to the synthesis of novel 12-phenylbenzo[6,7]oxepino[3,4-b]quinolin-13(6H)-one derivatives

• Wentao Gao,
• Guihai Lin,
• Yang Li,
• Xiyue Tao,
• Rui Liu and
• Lianjie Sun

Beilstein J. Org. Chem. 2012, 8, 1849–1857, doi:10.3762/bjoc.8.213

• -aminobenzophenone (1) with 4-chloroethylacetoacetate by using CAN (cerium ammonium nitrate, 10 mol %) as catalyst at room temperature. The substrates 3a–l were prepared through one-pot reaction of ethyl 2-(chloromethyl)-4-phenylquinoline-3-carboxylate (2) and substituted phenols. Our developed strategy, involving a