Glyco-gold nanoparticles: synthesis and applications

• Federica Compostella,
• Olimpia Pitirollo,
• Alessandro Silvestri and
• Laura Polito

Beilstein J. Org. Chem. 2017, 13, 1008–1021, doi:10.3762/bjoc.13.100

• metal-based anticancer drugs need to be developed. Recently, it has been reported the interesting synthesis of AuNPs coated with glyco-polymers and functionalized with gold(I) triphenylphosphine (Figure 7) [88]. This work showed the potentiality of these structures as novel cancer therapeutic drugs. The

Exploring endoperoxides as a new entry for the synthesis of branched azasugars

• Svenja Domeyer,
• Mark Bjerregaard,
• Henrik Johansson and
• Daniel Sejer Pedersen

Beilstein J. Org. Chem. 2017, 13, 644–647, doi:10.3762/bjoc.13.63

• was a Wittig reaction with methyltriphenylphosphonium iodide to provide 14–16. Compound 14 was found to be volatile and thus was only isolated in a poor yield. For diene 15 the low yield was largely due to complications with removing the triphenylphosphine oxide side product. However, at this stage

• anticipated that the reaction conditions could be optimised to favour the desired diol product. Ring contraction of acetonide-protected endoperoxide 23 by treatment with triphenylphosphine provided ready access to tetrahydrofuran 24 in good yield [21]. Finally, treatment of endoperoxide 23 with Co(salen) gave

Unpredictable cycloisomerization of 1,11-dien-6-ynes by a common cobalt catalyst

• Abdusalom A. Suleymanov,
• Dmitry V. Vasilyev,
• Valentin V. Novikov,
• Yulia V. Nelyubina and
• Dmitry S. Perekalin

Beilstein J. Org. Chem. 2017, 13, 639–643, doi:10.3762/bjoc.13.62

• (allyloxy)but-2-yne (1a) and 1,4-di(N-allyltosylamido)-2-butyne (1b) as test substrates for our investigation (Scheme 2). It was found that in the presence of CoBr2, Zn and ZnI2 (20 mol % each) as well as the triphenylphosphine ligand (40 mol %) in 1,2-dichloroethane (DCE) these substrates underwent clean

• derivative 2c in the presence of the triphenylphosphine ligand. More surprisingly, the same product was obtained when dppe or dppp were used as ligands, although the small amounts of isomeric by-products were detected in these cases. Noteworthy, according to the NMR spectra, product 2c was formed as a single

Brønsted acid-mediated cyclization–dehydrosulfonylation/reduction sequences: An easy access to pyrazinoisoquinolines and pyridopyrazines

• Ramana Sreenivasa Rao and
• Chinnasamy Ramaraj Ramanathan

Beilstein J. Org. Chem. 2017, 13, 428–440, doi:10.3762/bjoc.13.46

• reaction mixture was purified through silica gel column chromatography using ethyl acetate/hexane, 30:70 as eluent to afford 12a and 12b in the ratio 79:21. The regioisomers of bromopyrazinone (12a and 12b) (1.0 mmol), bis(triphenylphosphine)palladium(II) chloride (10 mol %, 7 mg) in dimethylformamide (2

Decarboxylative and dehydrative coupling of dienoic acids and pentadienyl alcohols to form 1,3,6,8-tetraenes

• Ghina’a I. Abu Deiab,
• Mohammed H. Al-Huniti,
• I. F. Dempsey Hyatt,
• Emma E. Nagy,
• Kristen E. Gettys,
• Sommayah S. Sayed,
• Christine M. Joliat,
• Paige E. Daniel,
• Rupa M. Vummalaneni,
• Andrew T. Morehead Jr,
• Andrew L. Sargent and
• Mitchell P. Croatt

Beilstein J. Org. Chem. 2017, 13, 384–392, doi:10.3762/bjoc.13.41

• greater amounts of triphenylphosphine lowering the reaction yield when using the Pd2dba3 catalyst (Table 1, entries 12–14). It was determined that reactions performed in the presence of electron-rich ligands had both quicker kinetics and more efficient yields compared to electron-deficient ligands (Table

Synthesis and optical properties of new 5'-aryl-substituted 2,5-bis(3-decyl-2,2'-bithiophen-5-yl)-1,3,4-oxadiazoles

• Anastasia S. Kostyuchenko,
• Tatyana Yu. Zheleznova,
• Anton J. Stasyuk,
• Aleksandra Kurowska,
• Wojciech Domagala,
• Adam Pron and
• Alexander S. Fisyuk

Beilstein J. Org. Chem. 2017, 13, 313–322, doi:10.3762/bjoc.13.34

• heating a mixture of ethyl 3-decyl-2,2'-bithiophene-5-carboxylate (7a) with aryl halides in the presence of tetrakis(triphenylphosphine)palladium(0) and AcOK in DMF for 20–22 h. Unfortunately, the yield of the phenyl-substituted product 7d remained low (18%), even when the reaction was performed for 55 h

Extrusion – back to the future: Using an established technique to reform automated chemical synthesis

• Deborah E. Crawford

Beilstein J. Org. Chem. 2017, 13, 65–75, doi:10.3762/bjoc.13.9

• well as the reaction between triphenylphosphine and nickel thiocyanate, both in the presence of stoichiometric amounts of MeOH (Figure 6) [2]. High-quality products were obtained, as determined by 1H NMR spectroscopy, PXRD analysis (which gave sharp diffraction patterns, indicating high crystallinity

Iodination of carbohydrate-derived 1,2-oxazines to enantiopure 5-iodo-3,6-dihydro-2H-1,2-oxazines and subsequent palladium-catalyzed cross-coupling reactions

• Michal Medvecký,
• Igor Linder,
• Luise Schefzig,
• Hans-Ulrich Reissig and
• Reinhold Zimmer

Beilstein J. Org. Chem. 2016, 12, 2898–2905, doi:10.3762/bjoc.12.289

• component in other Sonogashira couplings presented in former publications [23][32]. The reaction of syn-4a and alkyne 10 using palladium acetate, triphenylphosphine, and copper(I) iodide in a solvent mixture of diisopropylamine and DMF at room temperature gave the 5-(imidazolylethynyl)-substituted 1,2

Computational methods in drug discovery

• Sumudu P. Leelananda and
• Steffen Lindert

Beilstein J. Org. Chem. 2016, 12, 2694–2718, doi:10.3762/bjoc.12.267

• that by introducing a triphenylphosphine group into the base molecule pyridazinone, it is possible to obtain inhibitors for proteasome [2]. Further, analogs have been generated using this starting structure which showed high potency. Many studies show how CADD can influence the development of novel

From betaines to anionic N-heterocyclic carbenes. Borane, gold, rhodium, and nickel complexes starting from an imidazoliumphenolate and its carbene tautomer

• Ming Liu,
• Jan C. Namyslo,
• Martin Nieger,
• Mika Polamo and
• Andreas Schmidt

Beilstein J. Org. Chem. 2016, 12, 2673–2681, doi:10.3762/bjoc.12.264

• .12.264 Abstract The mesomeric betaine imidazolium-1-ylphenolate forms a borane adduct with tris(pentafluorophenyl)borane by coordination with the phenolate oxygen, whereas its NHC tautomer 1-(2-phenol)imidazol-2-ylidene reacts with (triphenylphosphine)gold(I) chloride to give the cationic NHC complex [Au

• on reaction with (triphenylphosphine)gold(I) chloride in boiling anhydrous THF under a nitrogen atmosphere, under which conditions the colorless gold complex [Au(6B)2][Cl] (9) is formed in 60% yield (Scheme 1). The protons of the OH resonate at δ = 10.34 ppm in DMSO-d6, and the 13C NMR chemical shift

• -cyclooctadiene)rhodium(I) dimer, or with bis(triphenylphosphine)rhodium(I) carbonyl chloride in anhydrous toluene at reflux temperature, respectively. During these reactions, the water of crystallization of the starting material is – at least partially – removed by azeotropic distillation and Rh(I) is obviously

New syntheses of (±)-tashiromine and (±)-epitashiromine via enaminone intermediates

• Darren L. Riley,
• Joseph P. Michael and
• Charles B. de Koning

Beilstein J. Org. Chem. 2016, 12, 2609–2613, doi:10.3762/bjoc.12.256

• planned reaction sequence was the alkylating cyclisation of the liberated alcohols 8a–c to produce the indolizidine nucleus (Scheme 2). The cyclisation was achieved by initially treating these deprotected enaminones with imidazole and triphenylphosphine at ambient temperature in acetonitrile followed by

• found that the bicyclic vinylogous urea 9d (64%) required a more careful flash chromatographic separation [19]. Unfortunately, the bicyclic vinylogous amide 9a could not be separated adequately from the triphenylphosphine residues under standard chromatographic and recrystallisation conditions. In an

• . We reverted to using the original procedure, but adjusted the purification protocol by first separating both the products and triphenylphosphine oxide residues from the baseline impurities by column chromatography, then removing most of the remaining triphenylphosphine residues by simple

Facile synthesis of a 3-deazaadenosine phosphoramidite for RNA solid-phase synthesis

• Elisabeth Mairhofer,
• Elisabeth Fuchs and
• Ronald Micura

Beilstein J. Org. Chem. 2016, 12, 2556–2562, doi:10.3762/bjoc.12.250

• catalysis at elevated pressure (30 psi) in ethanol or N,N-dimethylacetamide, ii) ammonium formiate, Pd/C, in methanol [28], iii) tin(II) chloride, in ethanol [29], iv) thioacetic acid, lutidine, in CH2Cl2 [30], v) triphenylphosphine, in CH2Cl2, aqueous work-up, and finally vi) Mg0 in methanol. Efficient 5

Efficient mechanochemical synthesis of regioselective persubstituted cyclodextrins

• Laszlo Jicsinszky,
• Marina Caporaso,
• Katia Martina,
• Emanuela Calcio Gaudino and
• Giancarlo Cravotto

Beilstein J. Org. Chem. 2016, 12, 2364–2371, doi:10.3762/bjoc.12.230

• to the known method [13], from freshly dried CDs on a 0.01 mol scale with triphenylphosphine and iodine in DMF. Per-6-bromo-γ-CD (2b’) was prepared in N-methylpyrrolidone by the same method using bromine. Per-6-chloro-β-CD (2a') was synthesized in a similar manner to per-6-iodo-CDs using p

A new and expeditious synthesis of all enantiomerically pure stereoisomers of rosaprostol, an antiulcer drug

• Wiesława Perlikowska,
• Remigiusz Żurawiński and
• Marian Mikołajczyk

Beilstein J. Org. Chem. 2016, 12, 2234–2239, doi:10.3762/bjoc.12.215

• rosaprostol methyl esters (−)-9 and (+)-9 in yields higher than 90%. Then the esters 9 were subjected to a Mitsunobu esterification under standard conditions (THF, rt) using p-nitrobenzoic acid (PNBA), triphenylphosphine and diisopropyl azodicarboxylate (DIAD). The p-nitrobenzoic acid esters (+)-10 and (−)-10

Palladium-catalyzed ring-opening reactions of cyclopropanated 7-oxabenzonorbornadiene with alcohols

• Katrina Tait,
• Oday Alrifai,
• Rebecca Boutin,
• Jamie Haner and
• William Tam

Beilstein J. Org. Chem. 2016, 12, 2189–2196, doi:10.3762/bjoc.12.209

• unsuccessful, palladium(II) catalysts in the absence of a triphenylphosphine ligand were more promising (Table 1, entries 6–9). The palladium(II) catalyst PdCl2(CH3CN)2 generated a high yield of substituted naphthalene 11a after only 24 hours and was chosen to further optimize reaction conditions. When the

• catalyst equivalency was investigated, lowering the catalyst from 10 mol % to 5 mol % reduced the yield from 89% to 27% (Table 1, entry 10) while further reducing the catalyst equivalency to 2 mol % showed no reaction (Table 1, entry 11). To confirm that the presence of a triphenylphosphine ligand would

• result in no reaction, the optimized catalyst was used with an external source of triphenylphosphine, which resulted in no reaction (Table 1, entry 12). To expand the scope of catalyst, the effect of using a platinum catalyst was investigated. The use of a platinum(IV) catalyst resulted in no reaction

Synthesis and characterization of fluorinated azadipyrromethene complexes as acceptors for organic photovoltaics

• Forrest S. Etheridge,
• Roshan J. Fernando,
• Sandra Pejić,
• Matthias Zeller and
• Geneviève Sauvé

Beilstein J. Org. Chem. 2016, 12, 1925–1938, doi:10.3762/bjoc.12.182

• (Aldrich), 4-ethynyl-α,α,α-trifluorotoluene (Aldrich), n-butyllithium solution (Aldrich), tributyltin chloride (Fisher), tributyl(phenylethynyl)tin (Aldrich), tetrakis(triphenylphosphine)palladium(0) (Aldrich), n-iodosuccinimide (abbreviated NIS, Aldrich) were used as received. All other reagents and

A flow reactor setup for photochemistry of biphasic gas/liquid reactions

• Josef Schachtner,
• Patrick Bayer and
• Axel Jacobi von Wangelin

Beilstein J. Org. Chem. 2016, 12, 1798–1811, doi:10.3762/bjoc.12.170

• convenience, reductive work-up with triphenylphosphine (PPh3) was performed to obtain the stable allyl alcohol derivative 3a which offers ample opportunities for chemical manipulations at the alcohol, alkene, and carboxamide functions. The choice of solvent is crucial as it determines the solubility of the

TMSBr-mediated solvent- and work-up-free synthesis of α-2-deoxyglycosides from glycals

• Mei-Yuan Hsu,
• Yi-Pei Liu,
• Sarah Lam,
• Su-Ching Lin and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2016, 12, 1758–1764, doi:10.3762/bjoc.12.164

• conditions in good to excellent yields. In addition, with triphenylphosphine oxide as an additive, the TMSBr-mediated direct glycosylations of glycals with a large range of alcohols were highly α-selective. Keywords: 2-deoxyglycosides; glycals; trimethylsilyl bromide (TMSBr); triphenylphosphine oxide (TPPO

Rearrangements of organic peroxides and related processes

• Ivan A. Yaremenko,
• Vera A. Vil’,
• Dmitry V. Demchuk and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162

• product, which rearranges into dioxetane 198 at 28 °C in CCl4 within 13 h. Compounds 198 can be further transformed into keto esters 199 by treatment for 24 h with triphenylphosphine in CCl4 or concentrated HCl in CCl4. When compound 197 is heated at 70 °C its rearrangement into 199 occurs very rapidly

Flow carbonylation of sterically hindered ortho-substituted iodoarenes

• Carl J. Mallia,
• Gary C. Walter and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2016, 12, 1503–1511, doi:10.3762/bjoc.12.147

• synthesis of ortho-substituted carboxylic acids, using carbon monoxide gas, has been studied for a number of substrates. The optimised conditions make use of a simple catalyst system compromising of triphenylphosphine as the ligand and palladium acetate as the pre-catalyst. Carbon monoxide was introduced

• -substituent directly over an axial site (Figure 1). The ortho-substituent therefore acts as a steric buttress hindering the approach of the incoming carbon monoxide thus slowing down the rate of the reaction. An X-ray structure of trans-bromo(o-tolyl)bis(triphenylphosphine)palladium(II) complex was reported

• -Phos (8) and triphenylphosphine (6) (Table 1, entries 2 and 5), with the difference between the conversion and the isolated yield mainly equating to the dehalogenated product namely, chlorobenzene. Next changing the amount of triethylamine used from 1.1 equiv to 1.6 equiv and 2.0 equiv, respectively

Application of Cu(I)-catalyzed azide–alkyne cycloaddition for the design and synthesis of sequence specific probes targeting double-stranded DNA

• Svetlana V. Vasilyeva,
• Vyacheslav V. Filichev and
• Alexandre S. Boutorine

Beilstein J. Org. Chem. 2016, 12, 1348–1360, doi:10.3762/bjoc.12.128

• Supporting Information File 1). This phenomenon has been already observed [24], though with quite low yields of products. These DNA derivatives were identified as products of incomplete departure of the oxidized triphenylphosphine moiety with the formation of the residue X covalently attached to the

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

• synthetic sequence of p-anisyl catalyst 1. In situ reduction of 4-methoxysulfonyl chloride by triphenylphosphine and trapping with (−)-menthol affords diastereomerically pure sulfinate ester 2 after enrichment by recrystallization [45]. Grignard addition attaches a TMS-protected alkyne of appropriate tether

• conversion by proton NMR. As seen in Table 4, when this experiment is performed with 3 mol % complex 1, a 54% conversion is observed after 1.5 hours (entry 1). When the same experiment is conducted with 3 mol % of CpRu(MeCN)3PF6 and 3 mol % triphenylphosphine, the reaction only proceeds to 15% conversion

Synthesis of a deuterated probe for the confocal Raman microscopy imaging of squalenoyl nanomedicines

• Eric Buchy,
• Branko Vukosavljevic,
• Maike Windbergs,
• Dunja Sobot,
• Camille Dejean,
• Simona Mura,
• Patrick Couvreur and
• Didier Desmaële

Beilstein J. Org. Chem. 2016, 12, 1127–1135, doi:10.3762/bjoc.12.109

• -bromopropane-d7 (8) with triphenylphosphine [29]. To our surprise, condensation of dialdehyde 5 with one equivalent of the ylide 4 (9, n-BuLi, THF, −78 °C) did not afford any amount of the desired deuterated olefin but only polar material that could not be characterized. In an attempt to find more efficient

Efficient syntheses of climate relevant isoprene nitrates and (1R,5S)-(−)-myrtenol nitrate

• Sean P. Bew,
• Glyn D. Hiatt-Gipson,
• Graham P. Mills and
• Claire E. Reeves

Beilstein J. Org. Chem. 2016, 12, 1081–1095, doi:10.3762/bjoc.12.103

• , the synthesis of either (E)-3-methyl-4-chlorobut-2-en-1-ol ((E)-60) or (Z)-3-methyl-4-chlorobut-2-en-1-ol ((Z)-61, Scheme 8). Reacting triphenylphosphine with 1-((2-bromoethoxy)methyl)-4-methoxybenzene (55) generated non-stabilized phosphonium ylide (2-(4-methoxybenzyloxy)ethyl)triphenylphosphonium

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

• , triphenylphosphine (Ph3P) and diethyl azodicarboxylate (DEAD) [9], versus addition of diisopropyl azodicarboxylate (DIAD) to the mixture of silibinin, acid and Ph3P [10]. In both cases, the desired C-23 ester was obtained in moderate yields, and we observed a side reaction, which we expected to be a dehydration

• Mitsunobu reaction represents a powerful method to convert primary and secondary alcohols into ester but also into various derivatives. The mechanism is well described and includes the formation of the triphenylphosphine–DIAD adduct, which then activates the alcohol making it a good leaving group