Synthesis of pyrrolo[2,1-f][1,2,4]triazin-4(3H)-ones: Rearrangement of pyrrolo[1,2-d][1,3,4]oxadiazines and regioselective intramolecular cyclization of 1,2-biscarbamoyl-substituted 1H-pyrroles

• Kkonnip Son and
• Seong Jun Park

Beilstein J. Org. Chem. 2016, 12, 1780–1787, doi:10.3762/bjoc.12.168

• discover drugs that are PI3K inhibitors, a Hutchison Medipharma patent caught our attention. They reported that pyrrolotriazinones showed excellent inhibitory activities against PI3K enzymes [9]. However, their synthetic method to prepare the target molecule 9 demonstrated a limited scope, and involved

Chiral cyclopentadienylruthenium sulfoxide catalysts for asymmetric redox bicycloisomerization

• Barry M. Trost,
• Michael C. Ryan and
• Meera Rao

Beilstein J. Org. Chem. 2016, 12, 1136–1152, doi:10.3762/bjoc.12.110

• more broadly accessible to our synthetic method (Table 6). While the 1,6-enyne substrates 36 and 38 exhibited the desired reactivity in THF, the enantioselectivities for the process were poor. Considering how impactful a judicious choice of solvent had on the enantioselectivity of the [4.1.0] bicycles

A cross-metathesis approach to novel pantothenamide derivatives

• Jinming Guan,
• Matthew Hachey,
• Lekha Puri,
• Vanessa Howieson,
• Kevin J. Saliba and
• Karine Auclair

Beilstein J. Org. Chem. 2016, 12, 963–968, doi:10.3762/bjoc.12.95

• replacing the geminal dimethyl moiety. Although quite versatile and stereoselective, the reported synthetic methodology to access such analogs decreases in efficiency with increasing size of the group used to replace the methyl residue [11] . We report here a synthetic method to access larger substituents

Reactions of N,3-diarylpropiolamides with arenes under superelectrophilic activation: synthesis of 4,4-diaryl-3,4-dihydroquinolin-2(1H)-ones and their derivatives

• Larisa Yu. Gurskaya,
• Diana S. Belyanskaya,
• Dmitry S. Ryabukhin,
• Denis I. Nilov,
• Irina A. Boyarskaya and
• Aleksander V. Vasilyev

Beilstein J. Org. Chem. 2016, 12, 950–956, doi:10.3762/bjoc.12.93

• rare objects, there is no general method for their synthesis [16][17]. Thus, developing of synthetic method to get these compounds is an actual goal of organic chemistry. Reactions of the series of 3-aryl-N-(aryl)propiolamides 1a–u, bearing various donor–acceptor substituents on aryl rings, with

Unconventional application of the Mitsunobu reaction: Selective flavonolignan dehydration yielding hydnocarpins

• Guozheng Huang,
• Simon Schramm,
• Jörg Heilmann,
• David Biedermann,
• Vladimír Křen and
• Michael Decker

Beilstein J. Org. Chem. 2016, 12, 662–669, doi:10.3762/bjoc.12.66

• the biologically important enantiomers of hydnocarpin D, hydnocarpin and isohydnocarpin, respectively. This represents the only one-pot semi-synthetic method to access these flavonolignans in high yields. Keywords: dehydration; flavonoid; hydnocarpin; Mitsunobu; silybin; Introduction Flavonolignans

New synthetic strategies for xanthene-dye-appended cyclodextrins

• Milo Malanga,
• Andras Darcsi,
• Mihaly Balint,
• Gabor Benkovics,
• Tamas Sohajda and
• Szabolcs Beni

Beilstein J. Org. Chem. 2016, 12, 537–548, doi:10.3762/bjoc.12.53

• fluorescent single-isomer CD [18]. If the substrate for the fluorescent labeling is a randomly substituted CD derivative, most commonly, the obtained mixture will contain fluorescently labelled and unlabeled isomers. In this work, our purpose was to develop a generic synthetic method for the derivatization of

Copper-mediated arylation with arylboronic acids: Facile and modular synthesis of triarylmethanes

• H. Surya Prakash Rao and
• A. Veera Bhadra Rao

Beilstein J. Org. Chem. 2016, 12, 496–504, doi:10.3762/bjoc.12.49

• of ferrocene-1-yl(phenyl)methanol (9d) with phenyboronic acid (10a) was facile and it provided diphenylmethylferrocene (11p) without any difficulty in 71% yield. Modular synthesis of triarylmethanes The synthetic method that we developed, through which three different aromatic rings on the central

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

• Hong-Bo Zhang Yong-Chun Luo Xiu-Qin Hu Yong-Min Liang Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering Lanzhou University, Lanzhou 730000, P. R. China 10.3762/bjoc.12.27 Abstract A new and efficient synthetic method to obtain fully

• -substituted hexahydroisoindolinones was developed by using bifunctional tertiary amine-thioureas as powerful catalysts. As far as we know, there is no efficient synthetic method developed toward fully-substituted hexahydroisoindolinones. The products were obtained in good yield and diastereoselectivity. The

• product is produced after the nucleophilic reaction, and the catalyst is regenerated (Scheme 3). Conclusion In summary, we have developed a one-pot quadruple cascade protocol to obtain fully-substituted hexahydroisoindolinones. This new, synthetic method is simple, efficient and atom-economic. This

Synthesis of bi- and bis-1,2,3-triazoles by copper-catalyzed Huisgen cycloaddition: A family of valuable products by click chemistry

• Zhan-Jiang Zheng,
• Ding Wang,
• Zheng Xu and
• Li-Wen Xu

Beilstein J. Org. Chem. 2015, 11, 2557–2576, doi:10.3762/bjoc.11.276

• et al. also developed this three-step procedure (CuAAC–deprotection–CuAAC) into a one-pot fashion with moderate overall yield (34–49%) [19]. Similar to Fiandanese’s strategy, Aizpurua et al. developed another synthetic method [20]: Starting with the CuAAC reaction of propargyl alcohol (7) with

• reaction was performed at low temperature (−35 °C) and high NaOH concentration. Subsequently, Jeon and co-workers reported a synthetic method for the construction of 5,5’-bitriazoles by using CuI together with 2 equiv of DIPEA [25]. The authors further demonstrated that the use of a base was also an

Comparison of the catalytic activity for the Suzuki–Miyaura reaction of (η⁵-Cp)Pd(IPr)Cl with (η³-cinnamyl)Pd(IPr)(Cl) and (η³-1-t-Bu-indenyl)Pd(IPr)(Cl)

• Patrick R. Melvin,
• Nilay Hazari,
• Hannah M. C. Lant,
• Ian L. Peczak and
• Hemali P. Shah

Beilstein J. Org. Chem. 2015, 11, 2476–2486, doi:10.3762/bjoc.11.269

• ; homogeneous catalysis; NHC ligands; palladium; Suzuki–Miyaura reaction; Introduction The Suzuki–Miyaura reaction is a powerful synthetic method for forming C–C bonds between aryl halides or pseudo halides and organoborane containing species [1][2][3][4][5]. The most active catalysts are generally based on Pd

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

• realized via a tandem Ullmann-type C–N coupling of the Ar–X bond and the amino group in 83 as well as the intramolecular amidation which was believed to assist the oxidative formation of the imine C=N bond (Scheme 22). By making use of this cascade synthetic method, Nagarajan et al. [78] finished the

Are D-manno-configured Amadori products ligands of the bacterial lectin FimH?

• Tobias-Elias Gloe,
• Insa Stamer,
• Cornelia Hojnik,
• Tanja M. Wrodnigg and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2015, 11, 1096–1104, doi:10.3762/bjoc.11.123

• ligation method for conjugation of unprotected sugars and amines, when applied to suitable sugar substrates. Herein, we evaluated this synthetic method for the preparation of ligands for the α-D-mannose-specific type 1-fimbrial bacterial lectin FimH. The synthesis of heptopyranose 8 as a starting material

Copper-catalyzed cascade reactions of α,β-unsaturated esters with keto esters

• Zhengning Li,
• Chongnian Wang and
• Zengchang Li

Beilstein J. Org. Chem. 2015, 11, 213–218, doi:10.3762/bjoc.11.23

• promising synthetic method for ester-functionalized γ-lactones and δ-lactones. Experimental A typical procedure: Under a N2 atmosphere, a solution of CuF(PPh3)3·2MeOH (1.9 mg, 0.0025 mmol), and Xantphos (1.2 mg, 0.0025 mmol) in toluene (1 mL) in a Schlenk tube was stirred for 15 min. PMHS (0.040 mL) was

Efficient deprotection of F-BODIPY derivatives: removal of BF₂ using Brønsted acids

• Mingfeng Yu,
• Joseph K.-H. Wong,
• Cyril Tang,
• Peter Turner,
• Matthew H. Todd and
• Peter J. Rutledge

Beilstein J. Org. Chem. 2015, 11, 37–41, doi:10.3762/bjoc.11.6

• -bromobenzaldehyde (7, Scheme 2B) respectively (see Supporting Information File 1 for experimental data). Preparation of nitro-F-BODIPY 8 was initially attempted by adapting the reported synthetic method [10]. However the ethereal complex 8·Et2O was isolated by flash column chromatography, rather than 8 itself

Visible-light-induced bromoetherification of alkenols for the synthesis of β-bromotetrahydrofurans and -tetrahydropyrans

• Run Lin,
• Hongnan Sun,
• Chao Yang,
• Youdong Yang,
• Xinxin Zhao and
• Wujiong Xia

Beilstein J. Org. Chem. 2015, 11, 31–36, doi:10.3762/bjoc.11.5

• . Keywords: alkenols; bromoetherification; photoredox catalysis; visible light; Introduction The halocyclization of alkenes provides an excellent synthetic method for halogenated heterocycles [1][2][3]. In recent years, haloaminocyclization [4][5], halolactonization [6][7] and haloetherification [8][9] of

A facile synthesis of functionalized 7,8-diaza[5]helicenes through an oxidative ring-closure of 1,1’-binaphthalene-2,2’-diamines (BINAMs)

• Youhei Takeda,
• Masato Okazaki,
• Yoshiaki Maruoka and
• Satoshi Minakata

Beilstein J. Org. Chem. 2015, 11, 9–15, doi:10.3762/bjoc.11.2

• , Yamadaoka 2-1, Suita, Osaka 565-0871, Japan 10.3762/bjoc.11.2 Abstract A facile and moderately functional-group-tolerant synthetic method for the preparation of 7,8-diaza[5]helicenes has been developed. It comprises of an oxidative ring-closing process of 1,1’-binaphthalene-2,2’-diamine (BINAM) derivatives

• finding prompted us to further explore the potential of this oxidative system as a facile and functional-group-tolerant synthetic method of this class of diazahelicenes, since no N-oxide byproducts are formed under this system and thereby any reduction processes using strong reductants are not needed

Come-back of phenanthridine and phenanthridinium derivatives in the 21st century

• Lidija-Marija Tumir,
• Marijana Radić Stojković and
• Ivo Piantanida

Beilstein J. Org. Chem. 2014, 10, 2930–2954, doi:10.3762/bjoc.10.312

• accompanied with simultaneous phosphorylation [42] (Scheme 19). The particular importance of this economic and highly efficient synthetic method is the complementarity of the starting material, the easy availability of 2-isocyanobiphenyls, which could be converted to variously substituted phenanthridines in

Synthesis of an organic-soluble π-conjugated [3]rotaxane via rotation of glucopyranose units in permethylated β-cyclodextrin

• Jun Terao,
• Yohei Konoshima,
• Akitoshi Matono,
• Hiroshi Masai,
• Tetsuaki Fujihara and
• Yasushi Tsuji

Beilstein J. Org. Chem. 2014, 10, 2800–2808, doi:10.3762/bjoc.10.297

• that we succeeded in the selective synthesis of 8 and 9 by simply changing the reaction solvent. We next applied this synthetic method to other π-conjugated guests. Scheme 3 shows the synthetic routes to precursor of PM β-CD based insulated oligothiophene. Mono-6-desmethyl PM β-CD alcohol 10 was

Synthesis of graft polyrotaxane by simultaneous capping of backbone and grafting from rings of pseudo-polyrotaxane

• Kazuaki Kato,
• Katsunari Inoue,
• Masabumi Kudo and
• Kohzo Ito

Beilstein J. Org. Chem. 2014, 10, 2573–2579, doi:10.3762/bjoc.10.269

• previously reported GPR, whereas the solubility of the GPR with short or sparse chains obtained in run 1 was not significantly different from that of PR without graft chains. Toward that end, we successfully simplified the synthesis of GPR. Conclusion We demonstrated a novel synthetic method toward GPRs

Oxidative phenylamination of 5-substituted 1-hydroxynaphthalenes to N-phenyl-1,4-naphthoquinone monoimines by air and light “on water”

• Julio Benites,
• Juan Meléndez,
• Cynthia Estela,
• David Ríos,
• Luis Espinoza,
• Iván Brito and
• Jaime A. Valderrama

Beilstein J. Org. Chem. 2014, 10, 2448–2452, doi:10.3762/bjoc.10.255

• conventional oxidative phenylamination procedures, this novel synthetic method offers the advantage of aerobic conditions “on water” instead of hazardous oxidant reagents currently employed in aqueous alcoholic media. Keywords: 1,4-naphthoquinone monoimines; on water; oxidative coupling; rose bengal; solar

Total synthesis of the proposed structure of astakolactin

• Takayuki Tonoi,
• Keisuke Mameda,
• Moe Fujishiro,
• Yutaka Yoshinaga and
• Isamu Shiina

Beilstein J. Org. Chem. 2014, 10, 2421–2427, doi:10.3762/bjoc.10.252

• already developed the synthetic method of lactones with various ring sizes using 2-methyl-6-nitrobenzoic anhydride (MNBA) under mild reaction conditions in the presence of a nucleophilic catalyst such as 4-(dimethylamino)pyridine (DMAP) [25][26]. By using this method, we have demonstrated that unusual

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

• with 1a as a model substrate to fully explore this new synthetic method (Table 1). Diamine product 5a was obtained in 83% yield when 1a reacted with benzylamine in acetonitrile at room temperature for 0.5 h (Table 1, entry 1). Increasing the temperature to 50 °C, gave no improvement on the yield (Table

Synthesis of ethoxy dibenzooxaphosphorin oxides through palladium-catalyzed C(sp²)–H activation/C–O formation

• Seohyun Shin,
• Dongjin Kang,
• Woo Hyung Jeon and
• Phil Ho Lee

Beilstein J. Org. Chem. 2014, 10, 1220–1227, doi:10.3762/bjoc.10.120

• -catalyzed C(sp2 and sp3)–H activation/C–O formation [42]. In this context, we herein report the synthetic method of alkoxy dibenzooxaphosphorin oxides from 2-(aryl)arylphosphonic acid monoesters via Pd-catalyzed C(sp2)–H activation/C–O formation (Scheme 1). Results and Discussion First, a wide range of 2

• ], resulting in the formation of palladacycle III. Thereafter, ethoxy dibenzooxaphosphorin oxide 2a is obtained from the oxidation of the Pd(II) to Pd(IV) species IV and the subsequent C–O reductive elimination. Conclusion In this paper, we have developed an efficient synthetic method for a wide range of

Solid-phase-supported synthesis of morpholinoglycine oligonucleotide mimics

• Tatyana V. Abramova,
• Sergey S. Belov,
• Yulia V. Tarasenko and
• Vladimir N. Silnikov

Beilstein J. Org. Chem. 2014, 10, 1151–1158, doi:10.3762/bjoc.10.115

• of the oligomer chain (Figure 2) depended on the utilized synthetic method. We found that the MorGly oligomers containing the residues of type A formed less stable complementary complexes than oligomers containing residues of type B. Another interesting fact demonstrated in the article [20] was the

Synthesis of zearalenone-16-β,D-glucoside and zearalenone-16-sulfate: A tale of protecting resorcylic acid lactones for regiocontrolled conjugation

• Hannes Mikula,
• Julia Weber,
• Dennis Svatunek,
• Philipp Skrinjar,
• Gerhard Adam,
• Rudolf Krska,
• Christian Hametner and
• Johannes Fröhlich

Beilstein J. Org. Chem. 2014, 10, 1129–1134, doi:10.3762/bjoc.10.112

• -glucoside than ZEN-14-glucoside in barley roots [17]. We therefore intended to develop a synthetic method for regiocontrolled conjugation of ZEN. Basically, the RAL type moiety of ZEN contains two possible sites for glycosylation/sulfation, but due to the higher reactivity of the phenol group at position 14