Inclusion complexes of 2-methoxyestradiol with dimethylated and permethylated β-cyclodextrins: models for cyclodextrin–steroid interaction

• Mino R. Caira,
• Susan A. Bourne,
• Halima Samsodien and
• Vincent J. Smith

Beilstein J. Org. Chem. 2015, 11, 2616–2630, doi:10.3762/bjoc.11.281

• (λmax = 198.5 nm) in methanol/water (1:1 v/v) solution. This instrument was also used for solubility and dissolution rate assays (details below). Single crystal X-ray diffraction analysis Intensity data were collected on a Nonius Kappa CCD diffractometer using graphite-monochromated Mo Kα-radiation (λ

Friedel–Crafts-type reaction of pyrene with diethyl 1-(isothiocyanato)alkylphosphonates. Efficient synthesis of highly fluorescent diethyl 1-(pyrene-1-carboxamido)alkylphosphonates and 1-(pyrene-1-carboxamido)methylphosphonic acid

• Anna Wrona-Piotrowicz,
• Janusz Zakrzewski,
• Anna Gajda,
• Tadeusz Gajda,
• Anna Makal,
• Arnaud Brosseau and
• Rémi Métivier

Beilstein J. Org. Chem. 2015, 11, 2451–2458, doi:10.3762/bjoc.11.266

• = 0.25) was assigned to π–π aggregates, the presence of which was revealed by single-crystal X-ray diffraction analysis. Keywords: amide; fluorescence; isothiocyanate; phosphonate; pyrene; thioamide; X-ray structure; Introduction Friedel–Crafts-type reaction of arenes with isothiocyanates constitutes a

A concise and efficient synthesis of benzimidazo[1,2-c]quinazolines through CuI-catalyzed intramolecular N-arylations

• Xinlong Pang,
• Chao Chen,
• Ming Li and
• Chanjuan Xi

Beilstein J. Org. Chem. 2015, 11, 2365–2369, doi:10.3762/bjoc.11.258

• (Scheme 2). It is worth mentioning that during the course of our study, we observed that products 4 were not stable to acid. For example, treatment of 4c with aqueous HCl solution led to ring-opening product 5 (Scheme 3). The structure of 5 was confirmed by X-ray diffraction analysis (Figure 1), clearly

New aryloxybenzylidene ruthenium chelates – synthesis, reactivity and catalytic performance in ROMP

• Patrycja Żak,
• Szymon Rogalski,
• Mariusz Majchrzak,
• Maciej Kubicki and
• Cezary Pietraszuk

Beilstein J. Org. Chem. 2015, 11, 1910–1916, doi:10.3762/bjoc.11.206

• of CuCl at 60 °C. After 24 h of the reaction course, the formation of a green precipitate was observed. X-ray diffraction analysis of single crystals obtained by slow evaporation of the post-reaction mixture revealed the formation of dimeric complex 16, in which the phenoxybenzylidene ring was

Synthesis and structures of ruthenium–NHC complexes and their catalysis in hydrogen transfer reaction

• Chao Chen,
• Chunxin Lu,
• Qing Zheng,
• Shengliang Ni,
• Min Zhang and
• Wanzhi Chen

Beilstein J. Org. Chem. 2015, 11, 1786–1795, doi:10.3762/bjoc.11.194

• molecular structures of the complexes 4 and 5 were also studied by X-ray diffraction analysis. These ruthenium complexes have proven to be efficient catalysts for transfer hydrogenation of various ketones. Keywords: N-heterocyclic carbene; ruthenium; transfer hydrogenation; Introduction N-Heterocyclic

• , the carbene carbons of complexes 4 and 5 are found at 190 and 200 ppm, respectively. The structures of 4 and 5 determined by X-ray diffraction analysis are shown in Figure 4 and Figure 5. In the cationic structure of 4, the acetonitrile ligand at the trans-position of the NHC is substituted by a

• catalyst solution (0.01 mmol, 0.001 mmol, or 0.0001 mol of ruthenium complexes in iPrOH (1 mL) was injected. Aliquots (0.2 mL) were taken at fixed time intervals, quenched with 1 mL of H2O and extracted with 3 mL of Et2O. The product yields were determined by GC analysis. X-ray diffraction analysis Single

Latent ruthenium–indenylidene catalysts bearing a N-heterocyclic carbene and a bidentate picolinate ligand

• Thibault E. Schmid,
• Florian Modicom,
• Adrien Dumas,
• Etienne Borré,
• Loic Toupet,
• Olivier Baslé and
• Marc Mauduit

Beilstein J. Org. Chem. 2015, 11, 1541–1546, doi:10.3762/bjoc.11.169

• , under these modified conditions the desired complex 4a could be prepared in a clean manner with an improved 62% isolated yield. Given the importance of the substitution pattern of the chelating [N–O] ligand, X-ray diffraction analysis unambiguously confirmed the structure of complex 4a, which displayed

Ruthenium indenylidene “1^st generation” olefin metathesis catalysts containing triisopropyl phosphite

• Stefano Guidone,
• Fady Nahra,
• Alexandra M. Z. Slawin and
• Catherine S. J. Cazin

Beilstein J. Org. Chem. 2015, 11, 1520–1527, doi:10.3762/bjoc.11.166

• with a cis-disposition of the phosphorus donor ligands. This geometry was confirmed by X-ray diffraction analysis on a single crystal (Figure 2). Synthesis of [RuCl2(Ind){P(OiPr)3}2] (2) The synthesis of the bis-phosphite species 2 was first attempted by the reaction of Ind-I with 2.5 equivalents of P

A new and efficient procedure for the synthesis of hexahydropyrimidine-fused 1,4-naphthoquinones

• Marcelo Isidoro P. Reis,
• Vinícius R. Campos,
• Jackson A. L. C. Resende,
• Fernando C. Silva and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2015, 11, 1235–1240, doi:10.3762/bjoc.11.137

• mass spectrometry. The synthesis of compounds 14 [43] and 17 [44] has been previously reported in the literature. The structure of compound 18 was confirmed by X-ray diffraction analysis and Figure 2 shows the ORTEP diagram of this compound. The details of the crystal data and refinements are collected

• ]+ of 395.1715. The structure of compound 23 was further elucidated by X-ray diffraction analysis (Figure 3). It confirmed the insertion of two imines to form a hexahydropyrimidine ring which is coupled to a 1,4-naphthoquinone moiety. Figure 3 shows the ORTEP diagram of compound 23 and the details of

• 1,3,5-triazinanes and products were confirmed by spectroscopical methods and X-ray diffraction analysis. General template for heterocycle-fused 1,4-naphthoquinones. ORTEP diagram of compound 18 depicted with ellipsoids drawn at the 50% probability level and the atom-numbering scheme. ORTEP diagram of

Regioselective synthesis of chiral dimethyl-bis(ethylenedithio)tetrathiafulvalene sulfones

• Flavia Pop and
• Narcis Avarvari

Beilstein J. Org. Chem. 2015, 11, 1105–1111, doi:10.3762/bjoc.11.124

• elemental analysis, which are all concordant, the definite proof for the sulfone structure of 1 has been provided by single crystal X-ray diffraction analysis. Single crystals of the two enantiomers (S,S)-1 and (R,R)-1 were obtained by slow evaporation from dichloromethane/pentane or dichloromethane

A new and convenient synthetic way to 2-substituted thieno[2,3-b]indoles

• Roman A. Irgashev,
• Arseny A. Karmatsky,
• Gennady L. Rusinov and
• Valery N. Charushin

Beilstein J. Org. Chem. 2015, 11, 1000–1007, doi:10.3762/bjoc.11.112

• reflectance attachment (DRA). X-ray diffraction analysis was performed on an automated X-ray diffractometer “Xcalibur E” on standard procedure. General procedure for the synthesis of 3-(2-oxo-2-(hetero)arylethylidene)indolin-2-one 10a−10o The solution of 1-alkylisatin 7 (3 mmol), corresponding methyl ketone 8

The reactions of 2-ethoxymethylidene-3-oxo esters and their analogues with 5-aminotetrazole as a way to novel azaheterocycles

• Marina V. Goryaeva,
• Yanina V. Burgart,
• Marina A. Ezhikova,
• Mikhail I. Kodess and
• Viktor I. Saloutin

Beilstein J. Org. Chem. 2015, 11, 385–391, doi:10.3762/bjoc.11.44

• good nucleofuge [28]. Indeed, the reaction of azidopyrimidine 2a with 5-AT made it possible to obtain 2-(tetrazolylamino)pyrimidine 5 in good yield (Scheme 2). The structure of pyrimidine 5 was confirmed by X-ray diffraction analysis (Figure 1). Further in this reaction we used 2

Azirinium ylides from α-diazoketones and 2H-azirines on the route to 2H-1,4-oxazines: three-membered ring opening vs 1,5-cyclization

• Nikolai V. Rostovskii,
• Mikhail S. Novikov,
• Alexander F. Khlebnikov,
• Galina L. Starova and
• Margarita S. Avdontseva

Beilstein J. Org. Chem. 2015, 11, 302–312, doi:10.3762/bjoc.11.35

• 60 °С: azirine 1c was completely consumed to give azadiene 3e isolated by column chromatography in 43% yield (Table 1, entry 5). The structure of azadiene 3e was confirmed by X-ray diffraction analysis (Figure 1). It should be noted that azadiene 3e in crystal exists in the s-trans-conformation

• characterized by standard spectral methods and the structures of adducts 6f and 7h were additionally confirmed by X-ray diffraction analysis (Figure 2). The reaction of diazoacetylacetone 2c with 2,3-diphenyl-2H-azirine (1a) provides oxazine 4i as a sole product (Table 1, entry 10). It was isolated with the

• conditions to the carbonyl group of oxazine 16. Actually, compound 17 formed in the reaction of a pure oxazine 16 with diazo compound 2c in the presence of Rh2(OAc)4. Its structure was assigned by standard spectral methods and confirmed by X-ray diffraction analysis (Figure 4). It was found that, when kept

Inclusion of trans-resveratrol in methylated cyclodextrins: synthesis and solid-state structures

• Lee Trollope,
• Dyanne L. Cruickshank,
• Terence Noonan,
• Susan A. Bourne,
• Milena Sorrenti,
• Laura Catenacci and
• Mino R. Caira

Beilstein J. Org. Chem. 2014, 10, 3136–3151, doi:10.3762/bjoc.10.331

• into a new vial, closed with a punctured polytop lid and was allowed to evaporate slowly on the benchtop or in an oven. The vial was sealed after crystals appeared. X-ray diffraction analysis All intensity data were collected on a Bruker KAPPA APEX II DUO diffractometer. In each case a single crystal

First chemoenzymatic stereodivergent synthesis of both enantiomers of promethazine and ethopropazine

• Paweł Borowiecki,
• Daniel Paprocki and
• Maciej Dranka

Beilstein J. Org. Chem. 2014, 10, 3038–3055, doi:10.3762/bjoc.10.322

• means of the assignment of the absolute configuration of the resolved enantiopure alcohol (S)-(+)-5 determined by a modified Mosher’s methodology, and was unambiguously confirmed by X-ray diffraction analysis. Optically active intermediates (S)-(+)-5 and (R)-(−)-7 achieved in this manner were

Formal total syntheses of classic natural product target molecules via palladium-catalyzed enantioselective alkylation

• Yiyang Liu,
• Marc Liniger,
• Ryan M. McFadden,
• Jenny L. Roizen,
• Jacquie Malette,
• Corey M. Reeves,
• Douglas C. Behenna,
• Masaki Seto,
• Jimin Kim,
• Justin T. Mohr,
• Scott C. Virgil and
• Brian M. Stoltz

Beilstein J. Org. Chem. 2014, 10, 2501–2512, doi:10.3762/bjoc.10.261

• ]. The relative stereochemistry of dysidiolide (29) was determined via single-crystal X-ray diffraction analysis, revealing a molecule with six stereocenters, two of which are quaternary carbons [45]. Several groups have reported total syntheses of this natural product [47][48][49][50][51][52][53], three

• –Danheiser chemistry [66][67]. E) Rhazinilam (−)-Rhazinilam (44) has been isolated from various plants including Rhazya strica decaisne [68], Melodinus australis [69], and Kopsia singapurensis [70]. Shortly after the first isolation, its structure was elucidated by single crystal X-ray diffraction analysis

Synthesis of 2-trifluoromethylpyrazolo[5,1-a]isoquinolines via silver triflate-catalyzed or electrophile-mediated one-pot tandem reaction

• Xiaoli Zhou,
• Meiling Liu,
• Puying Luo,
• Yingjun Lai,
• Tangtao Yang and
• Qiuping Ding

Beilstein J. Org. Chem. 2014, 10, 2286–2292, doi:10.3762/bjoc.10.238

• reaction conditions gave the desired product 3b in good yield (86%, Table 2, entry 2). The structure of 3b was verified by 1H and 13C NMR, HRMS, as well as X-ray diffraction analysis (Figure 1, for details, see Supporting Information File 1). As expected, the substrates 1e–h with electron-withdrawing

• 13C NMR, HRMS, as well as X-ray diffraction analysis (Figure 1, for details, see Supporting Information File 1). Based on this one-pot tandem electrophilic cyclization/[3 + 2] cycloaddition reactions, highly functionalized pyrazolo[5,1-a]isoquinolines can be obtained via palladium-catalyzed cross

(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

• unknown heterocycles 4а,b. Unambiguous evidence for the structure of heterocycle 4a was obtained by X-ray diffraction analysis [26]. The crystal structure of 4a is mediated by hydrogen bonds with a cation, a chloride anion and a solvating water molecule as participants (Figure 1). By acylation of 1

Derivatives of the triaminoguanidinium ion, 3. Multiple N-functionalization of the triaminoguanidinium ion with isocyanates and isothiocyanates

• Jan Szabo,
• Kerstin Karger,
• Nicolas Bucher and
• Gerhard Maas

Beilstein J. Org. Chem. 2014, 10, 2255–2262, doi:10.3762/bjoc.10.234

• (6c) reacted much more slowly than 6a,b. The molecular structure of 7a·3CH3CN in the solid state was established by a single crystal X-ray diffraction analysis and is shown in Figure 1 (vide infra for a discussion of structural details). It is interesting to note that the chloride anion is trapped

• ) 11b was isolated as a byproduct in 26% yield. The corresponding bis(arylthiourea) 11a could not be isolated, although its formation had been suggested by NMR spectra of the reaction mixture. The molecular structure of 10b was established by an X-ray diffraction analysis and is shown in Figure 4. The

Aryl substitution of pentacenes

• Andreas R. Waterloo,
• Anna-Chiara Sale,
• Dan Lehnherr,
• Frank Hampel and
• Rik R. Tykwinski

Beilstein J. Org. Chem. 2014, 10, 1692–1705, doi:10.3762/bjoc.10.178

• acenes can provide vital information about intermolecular interactions, single crystals of pentacenes 3a–d and 3g–j were grown and their solid-state arrangements determined by single crystal X-ray diffraction analysis (crystallographic details are provided in Supporting Information File 1). Pentacene 3a

Concise total synthesis of two marine natural nucleosides: trachycladines A and B

• Haixin Ding,
• Wei Li,
• Zhizhong Ruan,
• Ruchun Yang,
• Zhijie Mao,
• Qiang Xiao and
• Jun Wu

Beilstein J. Org. Chem. 2014, 10, 1681–1685, doi:10.3762/bjoc.10.176

• further unambiguously confirmed by X-ray diffraction analysis (Figure 3). This is the first report on the usage of SnCl4 as a regio- and stereoselective deprotection reagent in perbenzylated 5-deoxy-1-O-methylribofuranose. Based on these findings SnCl4 may prove useful for the regio- and stereoselective

Rasta resin–triphenylphosphine oxides and their use as recyclable heterogeneous reagent precursors in halogenation reactions

• Xuanshu Xia and
• Patrick H. Toy

Beilstein J. Org. Chem. 2014, 10, 1397–1405, doi:10.3762/bjoc.10.143

• trans configurations of the 9Ba and 9Bb were confirmed by X-ray diffraction analysis of the isolated products, and as was true for the Appel reactions described above, all the products were obtained in high purity simply by filtration to remove the polymer, and concentration of the filtrate. Our

Atherton–Todd reaction: mechanism, scope and applications

• Stéphanie S. Le Corre,
• Mathieu Berchel,
• Hélène Couthon-Gourvès,
• Jean-Pierre Haelters and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2014, 10, 1166–1196, doi:10.3762/bjoc.10.117

• chlorination such as the use of N-chlorosuccinimide or, as reported more recently, CuCl2 produced, in the latter case, 7-6 with full stereocontrol (Scheme 7-iii) as unambiguously determined by X-ray diffraction analysis [31]. The addition of nucleophilic species (amine, alcohol, alkyllithium, etc.) on 7-6 or

• and the stereochemistry of the products were unambiguously established by X-ray diffraction analysis. It is noteworthy that such coupling conditions have been extended to a wide variety of substrates including nitro-, methoxy-, trifluoromethylphenol or thiophenol with an almost similar reactivity

• hypothesis is strongly supported by X-ray diffraction analysis of a single crystal structure of the P–Cl intermediate species (Scheme 8). Thereafter, the reaction with phenol proceeds with an inversion of the configuration after a nucleophilic attack at the opposite side of the phosphorus–chlorine bond. In

Towards allosteric receptors – synthesis of β-cyclodextrin-functionalised 2,2’-bipyridines and their metal complexes

• Christopher Kremer,
• Gregor Schnakenburg and
• Arne Lützen

Beilstein J. Org. Chem. 2014, 10, 814–824, doi:10.3762/bjoc.10.77

• [(CO)3Re(14)Cl] complex obtained by X-ray diffraction analysis. Unfortunately, we were neither able to coordinate rhenium(I) to our bipyridines 1–3 nor did we succeed to prepare the rhenium complex [(CO)3Re(1)Cl] by using [(CO)3Re(14)Cl] and reacting it with aminocyclodextrin 21. Next, we tried copper

Group-assisted purification (GAP) chemistry for the synthesis of Velcade via asymmetric borylation of N-phosphinylimines

• Jian-bo Xie,
• Jian Luo,
• Timothy R. Winn,
• David B. Cordes and
• Guigen Li

Beilstein J. Org. Chem. 2014, 10, 746–751, doi:10.3762/bjoc.10.69

• hexane; the chiral N-phosphinyl auxiliary can be easily recovered after deprotection is finished. Several other N-phosphinylimines were also investigated for the asymmetric borylation reaction. The absolute configuration of the borylation product was confirmed by single crystal X-ray diffraction analysis

• and great stability in the catalytic borylation and deprotection reactions. GAP washing is found to enhance the diastereopurity of the borylation products in most cases. The absolute configuration of the borylation product in Velcade’s synthesis has been confirmed by single crystal X-ray diffraction

• analysis. Experimental Standard operations for catalytic borylation and GAP: A 10 mL Schlenk tube was charged with crude imine 2, B2Pin2 (375 mg, 2 equiv), catalyst ICyCuOt-Bu (54 mg, 20 mol %) and 4 Å molecular sieves (~500 mg). The mixture was protected with argon atmosphere, followed by toluene (4 mL

Copper–phenanthroline catalysts for regioselective synthesis of pyrrolo[3′,4′:3,4]pyrrolo[1,2-a]furoquinolines/phenanthrolines and of pyrrolo[1,2-a]phenanthrolines under mild conditions

• Rupankar Paira,
• Tarique Anwar,
• Maitreyee Banerjee,
• Yogesh P. Bharitkar,
• Shyamal Mondal,
• Sandip Kundu,
• Abhijit Hazra,
• Prakas R. Maulik and
• Nirup B. Mondal

Beilstein J. Org. Chem. 2014, 10, 692–700, doi:10.3762/bjoc.10.62

• ) also confirmed the structure. The relative orientations of H-1, H-18, H-19 and H-20 could be determined unambiguously by the single-crystal X-ray diffraction analysis of 10a; the ORTEP diagram is presented in Figure 2. No other diastereomer could be detected. The plausible mechanism of this