Synthesis and application of trifluoroethoxy-substituted phthalocyanines and subphthalocyanines

• Satoru Mori and
• Norio Shibata

Beilstein J. Org. Chem. 2017, 13, 2273–2296, doi:10.3762/bjoc.13.224

• diacetylene linkers, via a butadiyne and via an aryldiacetylene moiety (Figure 2). Such binuclear phthalocyanines that are connected via a rigid acetylene linker synthesized by Glaser or Sonogashira reactions have attracted attention due to their interesting effects resulting from further expansion of

The chemistry and biology of mycolactones

• Matthias Gehringer and
• Karl-Heinz Altmann

Beilstein J. Org. Chem. 2017, 13, 1596–1660, doi:10.3762/bjoc.13.159

Direct catalytic arylation of heteroarenes with meso-bromophenyl-substituted porphyrins

• Alexei N. Kiselev,
• Olga K. Grigorova,
• Alexei D. Averin,
• Sergei A. Syrbu,
• Oskar I. Koifman and
• Irina P. Beletskaya

Beilstein J. Org. Chem. 2017, 13, 1524–1532, doi:10.3762/bjoc.13.152

• via acetylene bridge [9]. All these compounds were synthesized from the corresponding aldehydes already possessing an heteroaromatic moiety. The development of the catalytic approaches opened an easy access to 2-aryl-substituted benzothiazoles, benzoxazoles and benzimidazoles. Kumada–Tamao–Corriu [10

Synthesis of novel 13α-estrone derivatives by Sonogashira coupling as potential 17β-HSD1 inhibitors

• Ildikó Bacsa,
• Rebeka Jójárt,
• János Wölfling,
• Gyula Schneider,
• Bianka Edina Herman,
• Mihály Szécsi and
• Erzsébet Mernyák

Beilstein J. Org. Chem. 2017, 13, 1303–1309, doi:10.3762/bjoc.13.126

• phenylacetylene using Pd(OAc)2 and CuI as catalysts [21]. They did not investigate the influence of the nature of the substituent on the phenyl ring of the acetylene on the course of the reactions. They carried out the full saturation of the C≡C bond of the 2-phenethynyl estrone with palladium on charcoal

Aggregation behaviour of a single-chain, phenylene-modified bolalipid and its miscibility with classical phospholipids

• Simon Drescher,
• Vasil M. Garamus,
• Christopher J. Garvey,
• Annette Meister and
• Alfred Blume

Beilstein J. Org. Chem. 2017, 13, 995–1007, doi:10.3762/bjoc.13.99

• alkyl chain of the bolalipid in order to fill the void volume. Besides heteroatoms [29][30], acetylene [31] or diacetylene groups [32], or methyl branches [31][33], also phenyl- or biphenyl rings were inserted into the long alkyl chain [34][35][36][37]. The insertion of a phenylene group led to PC

Interactions between shape-persistent macromolecules as probed by AFM

• Johanna Blass,
• Jessica Brunke,
• Franziska Emmerich,
• Cédric Przybylski,
• Vasil M. Garamus,
• Artem Feoktystov,
• Roland Bennewitz,
• Gerhard Wenz and
• Marcel Albrecht

Beilstein J. Org. Chem. 2017, 13, 938–951, doi:10.3762/bjoc.13.95

• backbone. Compared to monomer 7, peak broadening and the disappearance of the 1H NMR signals of the acetylene protons at 4.54 and 4.36 ppm indicate the formation of polymer 8. The presence of the conjugated backbone was confirmed by UV–vis and fluorescence measurements in water. Compared to 7, a

Transition-metal-free one-pot synthesis of alkynyl selenides from terminal alkynes under aerobic and sustainable conditions

• Adrián A. Heredia and
• Alicia B. Peñéñory

Beilstein J. Org. Chem. 2017, 13, 910–918, doi:10.3762/bjoc.13.92

• ). First, we explored the reactivity of KSeCN (2), n-octyl bromide (3a) and acetylene 6a in DMF as solvent under different atmospheric conditions (Table 1, entries 1–3). Conducting the reaction under an inert atmosphere, compound 5a was obtained with a yield of 38%. A slightly higher performance was

Nucleophilic and electrophilic cyclization of N-alkyne-substituted pyrrole derivatives: Synthesis of pyrrolopyrazinone, pyrrolotriazinone, and pyrrolooxazinone moieties

• Işıl Yenice,
• Sinan Basceken and
• Metin Balci

Beilstein J. Org. Chem. 2017, 13, 825–834, doi:10.3762/bjoc.13.83

• 9. Substituted alkyne derivatives 10a and 10b were synthesized according to the literature. The Sonogashira coupling reaction [25] of aryl iodides with terminal acetylene is an effective approach towards the synthesis of substituted arylalkynes. The reaction of 1-iodo-4-methoxybenzene and 1-iodo-4

A practical and efficient approach to imidazo[1,2-a]pyridine-fused isoquinolines through the post-GBB transformation strategy

• Taofeng Shao,
• Zhiming Gong,
• Tianyi Su,
• Wei Hao and
• Chao Che

Beilstein J. Org. Chem. 2017, 13, 817–824, doi:10.3762/bjoc.13.82

• acetylene unit may then undergo a sequential 6-exo-dig cyclization/retro-ene reaction to form the desired imidazo[1,2-a]pyridine-fused isoquinoline 6a. The cyclization reaction could be realized with the aid of silver or gold catalysts [51][52]. With this idea in mind, we commenced our studies by

• -ethynylbenzaldehydes 2 and tert-butylisocyanide (3). Indeed, the acetylene group in the aldehyde component had no obvious steric effect on the efficiency of the GBB reaction affording the GBB product in good to excellent yields in most cases. On the other hand, the substituent ortho to the amino group in the amidine

Effect of the ortho-hydroxy group of salicylaldehyde in the A³ coupling reaction: A metal-catalyst-free synthesis of propargylamine

• Sujit Ghosh,
• Kinkar Biswas,
• Suchandra Bhattacharya,
• Pranab Ghosh and
• Basudeb Basu

Beilstein J. Org. Chem. 2017, 13, 552–557, doi:10.3762/bjoc.13.53

• acetylene, established as a general protocol, and is believed to be of interest for synthetic chemists from green chemistry. Keywords: A3 coupling; metal-catalyst-free; propargylamine; salicylaldehyde; terminal alkyne; Introduction Propargylamines are important synthetic intermediates for the preparation

• activate the terminal acetylene primarily, which then undergoes a nucleophilic addition to the iminium electrophile generated from the aldehyde and the amine. Among different transition metals, copper metal has been mostly explored as the catalyst to activate the terminal acetylene, though there is a

• this case, activation of the Csp–COOH occurs via decarboxylation followed by the coupling with an iminium electrophile to produce the propargylamine. Although the strategy is interesting, functionalized acetylene carboxylic acids are difficultly accessible and the reaction is less 'atom economic

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

• coupling. For this purpose, we selected (trimethylsilyl)acetylene as alkyne component. The Sonogashira couplings of 5-iodo-1,2-oxazines syn-4a and anti-4a were carried out under standard conditions using a catalytic system consisting of PdCl2(PPh3)2, CuI and triethylamine in toluene at room temperature to

Multicomponent synthesis of spiropyrrolidine analogues derived from vinylindole/indazole by a 1,3-dipolar cycloaddition reaction

• Manjunatha Narayanarao,
• Lokesh Koodlur,
• Vijayakumar G. Revanasiddappa,
• Subramanya Gopal and
• Susmita Kamila

Beilstein J. Org. Chem. 2016, 12, 2893–2897, doi:10.3762/bjoc.12.288

• stereospecific cyclic adducts. Keywords: L-proline; ninhydrin; sarcosine; spiropyrrolidine; 5-vinylindazole; 5-vinylindole; Introduction The [3 + 2] cycloaddition between azomethine ylides and olefins/acetylene as dipolarophiles is an important reaction to access a number of novel heterocyclic spiro scaffolds

Thiophene-forming one-pot synthesis of three thienyl-bridged oligophenothiazines and their electronic properties

• Dominik Urselmann,
• Konstantin Deilhof,
• Bernhard Mayer and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2016, 12, 2055–2064, doi:10.3762/bjoc.12.194

• , 0.08 mmol), CuI (15.0 mg, 0.08 mmol), PPh3 (21 mg, 0.08 mmol), (trimethylsilyl)acetylene (0.56 mL, 2.00 mmol), and piperidine (5.00 mL, 50.4 mmol) were added. The closed vessel under nitrogen was heated at 55 °C (oil bath) for 16 h. Next, TBAF·3H2O (631 mg, 2.00 mmol) was added and the vessel open to

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

• ][33][34]. (4-Fluorophenylethynyl)tributyltin (for the synthesis of L3), and [4-(trifluoromethyl)phenyl](tributyltin)acetylene (for the synthesis of L4) were synthesized according to literature procedures with minor modifications and used without purification [35][36]. Methods 1H, 19F, and 13C NMR

• , 684.39. L4: [4-(Trifluoromethyl)phenyl](tributyltin)acetylene (0.686 g, 1.495 mmol) and ADPI2 (0.313 g, 0.445 mmol) was taken into a Schlenk flask (100 mL), which was evacuated and refilled with N2 three times. Distilled xylenes (50 mL) were added to the flask using a syringe and placed under slight

• vacuum. Then Pd(PPh3)4 (0.049g, 10 mmol %) was added inside a glove box. The mixture was heated at 125 °C for 48 h under N2. After 48 h, additional [4-(trifluoromethyl)phenyl](tributyltin)acetylene (0.686 g, 1.495 mmol) and Pd(PPh3)4 (0.049g, 10 mmol %) were added in one shot. The reaction mixture was

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

• , O3, H2, Cl2, acetylene, NOx, CO, CO2, etc.) but obviously bear several challenges with regard to a reproducible and precise control of the addition and mixing of the three phases: the liquid phase, containing organic substrates, the photo-active component (catalyst or sensitizer), the solvent, and

Discovery of an inhibitor of the production of the Pseudomonas aeruginosa virulence factor pyocyanin in wild-type cells

• Bernardas Morkunas,
• Balint Gal,
• Warren R. J. D. Galloway,
• James T. Hodgkinson,
• Brett M. Ibbeson,
• Yaw Sing Tan,
• Martin Welch and
• David R. Spring

Beilstein J. Org. Chem. 2016, 12, 1428–1433, doi:10.3762/bjoc.12.137

• intramolecular cyclisation of an analogous β-ketoamide in sulphuric acid [27], or pallidum catalysed intramolecular cyclisation of an acetylene derivative under acidic conditions [28]. The 4-alkylquinolin-2(1H)-one molecular scaffold of compound 4 is clearly distinct from that of AHLs; to the best of our

Reactivity studies of pincer bis-protic N-heterocyclic carbene complexes of platinum and palladium under basic conditions

• David C. Marelius,
• Curtis E. Moore,
• Arnold L. Rheingold and
• Douglas B. Grotjahn

Beilstein J. Org. Chem. 2016, 12, 1334–1339, doi:10.3762/bjoc.12.126

• and of the C–H bond of acetylene. The same ligand in CpRu complexes 2 and 3 showed heterolysis of dihydrogen [13]. 1 had a much faster ligand exchange rate after ionization as compared to the Cp*Ir analog (ethylene bound in 5 min at rt (CpRu) instead of 16 h at 70 °C (Cp*Ir)). Species 1 could be

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

• [4][5]. Many of these synthetical protocols are based on alkynes, which are widely used for the preparation of various carbo- and heterocycles [6][7][8][9][10]. Based on our works on the synthesis of 4-arylquinolin-2(1H)-ones from acetylene compounds under superelectrophilic activation conditions [11

• Discussion The protonation of alkynamides 1 on both the oxygen atom of the amide group and a carbon atom of the acetylene bond in superacids or coordination of these basic centers with strong Lewis acids leads to the formation of dications A that are considered as superelectrophiles [15] (Scheme 1). These

• phenyl group). Amides 1, bearing various donor (Me, MeO, benzo-) and acceptor (F, Cl) substituents on both aryl rings at the acetylene bond and at the nitrogen atom may be involved in this reaction. Substrates 1g, 1h, having electron withdrawing 4-F and 4-Cl substituents on the N-aryl ring, were hardly

Study on the synthesis of the cyclopenta[f]indole core of raputindole A

• Nils Marsch,
• Mario Kock and
• Thomas Lindel

Beilstein J. Org. Chem. 2016, 12, 334–342, doi:10.3762/bjoc.12.36

• included the second indole moiety of raputindole A (1). Boc protection of 6-iodoindole (2) [35], Sonogashira reaction of 3 with TMS-acetylene, and desilylation gave the N-protected alkynylindole 4 in excellent yield (Scheme 2). Boc-iodoindole 3 was also the precursor of the coupling partner, ketone 6

• Chancellor and coworkers [42], gave nitrophenol 11 in a reasonable yield (45%). The Batcho–Leimgruber protocol failed for nitrophenol 11 [43]. However, after O-benzylation of 11 to 12, Boc-indole 15 was obtained in the very good yield of 91%. Coupling with TMS-acetylene was followed by desilylation to obtain

Hydroquinone–pyrrole dyads with varied linkers

• Hao Huang,
• Christoffer Karlsson,
• Maria Strømme,
• Martin Sjödin and
• Adolf Gogoll

Beilstein J. Org. Chem. 2016, 12, 89–96, doi:10.3762/bjoc.12.10

• material for the corresponding phosphonate. However, neither n-BuLi nor t-BuOK used as base succeeded to give the desired product. Acetylene linker: Synthesis of 3-((2,5-dimethoxyphenyl)ethynyl)-1H-pyrrole (3d) The synthesis strategy for the ethynyl-linked compound 3d was straightforward, using a

Enantioselective additions of copper acetylides to cyclic iminium and oxocarbenium ions

• Jixin Liu,
• Srimoyee Dasgupta and
• Mary P. Watson

Beilstein J. Org. Chem. 2015, 11, 2696–2706, doi:10.3762/bjoc.11.290

• terminal alkyne to the enamine simultaneously generates the copper acetylide and iminium ion, which are proposed to both bind to the chiral copper catalyst (see 4). A broad scope in the acetylene was observed, with arylalkynes resulting in the highest ee’s. To our knowledge, these were the first

• reaction time could be reduced. Addition of alkynes with aryl, alkyl and trimethylsilyl substituents were successful, with the highest enantioselectivity observed when (trimethylsilyl)acetylene was used (94% ee). Just before Li’s report of the alkynlation of N-arylisoquinolinium ions, Taylor and Schreiber

• reported a CuBr/Quinap-catalyzed alkynylation of N-alkylisoquinolinium ions (Scheme 5) [25]. Similar to Li’s alkynylation of N-arylisoquinolinium ions, alkynes with various substituents can be used successfully, and the highest ee’s were observed when (trimethylsilyl)acetylene was used (99% ee). Most of

Lewis acid-promoted hydrofluorination of alkynyl sulfides to generate α-fluorovinyl thioethers

• Davide Bello and
• David O'Hagan

Beilstein J. Org. Chem. 2015, 11, 1902–1909, doi:10.3762/bjoc.11.205

• somewhat scarce. The only account we are aware of involves the AIBN-promoted thiodesulfonylation of aromatic fluorovinyl sulfones as reported by Wnuk [12], a reaction which works in varying yields and stereoselectivities. Following from our previous experience [7] with terminal acetylene thioethers, we now

Polythiophene and oligothiophene systems modified by TTF electroactive units for organic electronics

• Alexander L. Kanibolotsky,
• Neil J. Findlay and
• Peter J. Skabara

Beilstein J. Org. Chem. 2015, 11, 1749–1766, doi:10.3762/bjoc.11.191

• -deficient acetylene compounds (Scheme 6). By reacting 23 with 24a this method provides diester 25a in good yield [63]. Compound 25a can be reduced to diol 25d [64] and further converted by either the Appel method [59] or by reaction with PBr3 [65] into dibromomethyl compound 21, which is required for

• synthetic pathway A. Even though the reaction of 23 with acetylene compound 24b (containing only one electron-withdrawing group) is efficient, affording 25b with a 60% yield [66], attempts to invoke cycloaddition of 23 and 24c in a similar manner led to a poor yield of 25c (8%) [60]. An efficient method for

Synthesis of alpha-tetrasubstituted triazoles by copper-catalyzed silyl deprotection/azide cycloaddition

• Zachary L. Palchak,
• Paula T. Nguyen and
• Catharine H. Larsen

Beilstein J. Org. Chem. 2015, 11, 1425–1433, doi:10.3762/bjoc.11.154

• Scheme 1 would streamline the synthesis of alpha-tetrasubstituted triazoles 6. In the first step, our solvent-free copper-catalyzed three-component coupling of cyclohexanone (1), amines 2, and alkynes 3 provides high yields of silyl-protected propargylic amines 4 [24][25]. Trimethylsilyl (TMS) acetylene

• was not stable in the presence of the copper(II) chloride catalyst, and triethylsilylacetylene did not convert cleanly to product. Triisopropylsilyl (TIPS) acetylene was found to be superior to tert-butyldimethylsilylacetylene as a source of silylated tetrasubstituted propargylic amines. Although TMS

• starting materials, cyclohexanone (1), 4-methylpiperidine (2a), and TIPS-acetylene (3). As there are no added ligands, solvents, promoters, or excess starting materials, the sole byproduct in the formation of tetrasubstituted propargylamine 4a is one equivalent of water [25]. The second step links silyl

Synthesis of γ-hydroxypropyl P-chirogenic (±)-phosphorus oxide derivatives by regioselective ring-opening of oxaphospholane 2-oxide precursors

• Iris Binyamin,
• Shoval Meidan-Shani and
• Nissan Ashkenazi

Beilstein J. Org. Chem. 2015, 11, 1332–1339, doi:10.3762/bjoc.11.143

• . Further heating did not provide higher conversion. Following hydrolytic work-up and flash chromatographic purification the product was identified as allene 5f, rather than acetylene 5h, due to propargyl–allene rearrangement (Scheme 5). Most characteristic are the 13C NMR chemical shift of HC=C=CR at

• serve as the catalytic base that prompts the rearrangment. The 1,3-hydrogen shift in a P-propargyl system is well established [51]. In an attempt to prevent this rearrangement we applied an acetylene substituted with the bulky TMS group [58], which may be easily removed at a later stage, and formed the

• formed regioselectivly. Synthesis of acetylene and allene phosphine oxides. Synthesis of γ-hydroxypropyl (±)-phosphinatesa and related compounds. Synthesis of γ-hydroxypropyl (±)-phosphine oxidesa. Supporting Information Supporting Information File 66: Experimental details, characterization data and 1H