Dinuclear thiazolylidene copper complex as highly active catalyst for azid–alkyne cycloadditions

• Anne L. Schöffler,
• Ata Makarem,
• Frank Rominger and
• Bernd F. Straub

Beilstein J. Org. Chem. 2016, 12, 1566–1572, doi:10.3762/bjoc.12.151

• structure of hexafluorophosphate salt 1b (CCDC 1472789). Color code: black carbon, grey hydrogen, yellow sulfur, blue nitrogen, magenta phosphorus, green fluorine. Time-conversion-diagram of the CuAAC reaction of benzyl azide with either phenylacetylene or ethyl propiolate in the presence of copper complex

Enantioselective addition of diphenyl phosphonate to ketimines derived from isatins catalyzed by binaphthyl-modified organocatalysts

• Hee Seung Jang,
• Yubin Kim and
• Dae Young Kim

Beilstein J. Org. Chem. 2016, 12, 1551–1556, doi:10.3762/bjoc.12.149

• properties [5], enzyme inhibition [6], peptide mimetic function [7], and herbicidal properties [8]. Since the biological activity of α-aminophosphonate derivatives is dependent upon the chirality of the α-position to the phosphorus atom, asymmetric synthesis of α-aminophosphonates has received considerable

Microwave-assisted synthesis of (aminomethylene)bisphosphine oxides and (aminomethylene)bisphosphonates by a three-component condensation

• Erika Bálint,
• Ádám Tajti,
• Anna Dzielak,
• Gerhard Hägele and
• György Keglevich

Beilstein J. Org. Chem. 2016, 12, 1493–1502, doi:10.3762/bjoc.12.146

• ]. (Aminomethylene)bisphosphonates can also be obtained starting from amides, triethyl phosphite and phosphorus oxychloride (Scheme 3a) [37], or in the reaction of amines with diazophosphonate in the presence of a rhodium catalyst (Scheme 3b) [38]. (Aminomethylene)bisphosphine oxides are analogous to (aminomethylene

Beta-hydroxyphosphonate ribonucleoside analogues derived from 4-substituted-1,2,3-triazoles as IMP/GMP mimics: synthesis and biological evaluation

• Tai Nguyen Van,
• Audrey Hospital,
• Corinne Lionne,
• Lars P. Jordheim,
• Charles Dumontet,
• Christian Périgaud,
• Laurent Chaloin and
• Suzanne Peyrottes

Beilstein J. Org. Chem. 2016, 12, 1476–1486, doi:10.3762/bjoc.12.144

• similar binding poses with respect to the positions of the oxygens linked to the phosphorus atom (strong ionic interactions with the magnesium ion), the ribose moiety (formation of hydrogen bonds between the hydroxy groups and Lys215) and the triazole ring oriented towards the hydrophobic residues Phe157

Ring-whizzing in polyene-PtL₂ complexes revisited

• Oluwakemi A. Oloba-Whenu,
• Thomas A. Albright and
• Chirine Soubra-Ghaoui

Beilstein J. Org. Chem. 2016, 12, 1410–1420, doi:10.3762/bjoc.12.135

• space the groups around the phosphorus atoms have been removed. COT and C8F8 have a tub shaped structure with D2d symmetry [53][54]. As expected an η2 structure, 28, was found to be a minimum. A 1,4-diyl minimum was also found where there are two Pt–C σ bonds, 30. This structure has also been suggested

• with their relative energies in Figure 12. Here again the hydrogens and ethano-bridge connected to the phosphorus atoms has been removed for clarity. We find that the η2 structure, 40, to be the ground state. A low energy η3 transition state, 41, at 7.7 kcal/mol serves to equivalence the top and bottom

• are the two optimized structures of C3H3–Pt(dpe)+. Two unoccupied MOs for Cp+ are shown on the left side. The two stationary points for Cp–Pt(dpe)+ are given by 13 and 14. To conserve space the groups around the phosphorus atoms have been removed. The half-filled degenerate π orbitals in

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

• phosphorus of the terminal phosphate (Figure 9, insert). Attempts to eliminate this residue by treatment with aqueous 25% ammonia have not been successful. However, it was shown later that this residue does not prevent the subsequent CuAAC reactions with the azido-containing molecules. In view of these

Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

• Mohammad Haji

Beilstein J. Org. Chem. 2016, 12, 1269–1301, doi:10.3762/bjoc.12.121

• . As shown in this review, they play an important role in organophosphorus chemistry where phosphorus reagents are used as substrates for the synthesis of a wide range of phosphorylated heterocycles. In this article, an overview about multicomponent reactions used for the synthesis of heterocyclic

• compounds bearing a phosphonate group on the ring is given. Keywords: multicomponent reactions; organophosphorus chemistry; phosphorus reagents; phosphorylated heterocycles; Introduction Heterocyclic rings are found in many naturally occurring compounds and they compose the core structures of many

• were obtained which were sterically too crowded for attacking the phosphorus atom of the phosphonates. The use of unsymmetrically substituted diamines led to the corresponding syn-regioisomers as the major product and the anti-regioisomer as the minor product. Some of the synthesized 1,5-benzodiazepin

Synthesis, fluorescence properties and the promising cytotoxicity of pyrene–derived aminophosphonates

• Jarosław Lewkowski,
• Maria Rodriguez Moya,
• Anna Wrona-Piotrowicz,
• Janusz Zakrzewski,
• Renata Kontek and
• Gabriela Gajek

Beilstein J. Org. Chem. 2016, 12, 1229–1235, doi:10.3762/bjoc.12.117

• -yl)methyleneamine [17], a N-(1-pyrene)methylideneglucosamine mercury complex [18], a N-(pyren-1-ylidene)-2-hydroxyaniline-copper(II) and -zinc(II) complexes [19] or N-(pyren-1-ylidene)-4-carboxyaniline-Fe(II) and -Cr(III) complexes [20]. Several phosphorus-supported ligands containing a pyrene-1

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

• electrophilic nature of the desired allylic halides (viz. use of allylic chloride and 10 mol % sodium iodide in Scheme 9) we opted to transform 1° alcohols (E)-66 and (Z)-67 into their corresponding allylic bromides (not shown). This was straightforward and efficient using phosphorus tribromide in ether at 0 °C

A modular approach to neutral P,N-ligands: synthesis and coordination chemistry

• Vladislav Vasilenko,
• Torsten Roth,
• Clemens K. Blasius,
• Sebastian N. Intorp,
• Hubert Wadepohl and
• Lutz H. Gade

Beilstein J. Org. Chem. 2016, 12, 846–853, doi:10.3762/bjoc.12.83

• hydrogenations [1][2] and allylic substitutions [3][4] to Heck reactions [5] and conjugate additions to enones [6]. Their popularity arises from the inherent electronic disparity of the phosphorus and the nitrogen donor groups, rendering one binding site a soft π-acceptor featuring a pronounced trans effect and

• . In addition, the resulting ligand families should provide nitrogen and phosphorus donors with varying donor strength (amidine vs imine, phosphine vs heteroatom-bound phosphorus) and different bite angles (five- vs six-membered chelate rings). Results and Discussion Ligand synthesis We based the

• and 3a–c that can exist in solution, depending on the orientation of the phosphorus lone pair, the geometry of the C=N double bond and the orientation of the substituents of the C–N single bond [12]. Notably, all synthesized derivatives feature a single signal in the 31P NMR spectrum at room

Nucleic acids through condensation of nucleosides and phosphorous acid in the presence of sulfur

• Tuomas Lönnberg

Beilstein J. Org. Chem. 2016, 12, 670–673, doi:10.3762/bjoc.12.67

• nucleic acid polymerizations described so far have utilized activated starting materials, such as cyclic phosphates [1][2] or phosphoroimidazolides [3][4]. The trivalent phosphorus atom of phosphorous acid is much more susceptible to a nucleophilic attack than the pentavalent phosphorus atom of phosphoric

• acid [5]. Furthermore, phosphite salts are up to 1000-fold more soluble in water than phosphate salts [6]. For these reasons, compounds of reduced phosphorus (i.e., phosphorus at oxidation state lower than +5) were first proposed to have played a role in prebiotic phosphorylation reactions as early as

• 1955 [7]. Since then, both terrestrial [8] and extraterrestrial [9] sources of reduced phosphorus have been identified. Recent studies suggest the presence of significant amounts of phosphite in the Archean ocean, lending support to the idea of prebiotic phosphite chemistry [10][11]. Monoesters of

Aluminacyclopentanes in the synthesis of 3-substituted phospholanes and α,ω-bisphospholanes

• Vladimir A. D’yakonov,
• Alevtina L. Makhamatkhanova,
• Rina A. Agliullina,
• Leisan K. Dilmukhametova,
• Tat’yana V. Tyumkina and
• Usein M. Dzhemilev

Beilstein J. Org. Chem. 2016, 12, 406–412, doi:10.3762/bjoc.12.43

• efficient one-pot process for the synthesis of 3-substituted phospholanes and α,ω-bisphospholanes was developed. The method involves the replacement of aluminium in aluminacyclopentanes, prepared in situ by catalytic cycloalumination of α-olefins and α,ω-diolefins, by phosphorus atoms on treatment with

• organophosphorus compounds (OPC) is the direct transformation of five-membered metallacarbocycles based on transition metals to phosphacarbocycles on treatment with phosphorus dihalides. For example, a method for the direct conversion of zirconacyclopentenes [1][2][3][4] and zirconacyclopentadienes [5] to

• substituted phospholenes [6] and phospholes [7] has been reported. This approach was used to obtain materials for light-emitting diodes (LEDs) [8], phosphorus-containing polymers [9][10], bisphospholes [11], bicyclodiphospholanes and spirobicyclodiphospholanes [12][13]. However, this method is faced with some

Interactions of cyclodextrins and their derivatives with toxic organophosphorus compounds

• Sophie Letort,
• Sébastien Balieu,
• William Erb,
• Géraldine Gouhier and
• François Estour

Beilstein J. Org. Chem. 2016, 12, 204–228, doi:10.3762/bjoc.12.23

• organophosphorus (NOPs) share a typical structure with a pentavalent phosphorus atom linked to a leaving group (LG), two substituents (R1 and R2) and an oxygen or a sulfur atom (Figure 1), explaining the wide structural diversity of organophosphates. They can be classified into three categories depending on the

• radius whereas the β- and γ-CDs’ primary alcohols cones are similar. The guest molecule’s inclusion depth corresponds to the distance from the phosphorus atom to the secondary OH rim. As this distance is the highest with γ-CD, diazinon (5, Figure 3) is more deeply inserted [47]. According to these

• in the mode of inclusion. For instance, aromatic ring as substituent of the phosphorus atom are often included into the cavity, while steric hindrance is able to impair the complex formation. Finally, without aromatic groups, the mode of entry of the pesticide depends on the specific affinity of the

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

• Xinlong Pang Chao Chen Ming Li Chanjuan Xi Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China, Tel: +86-10-62773684 College of Chemistry and Molecular Engineering, Qingdao University of

Life lessons

• Jonathan R. Nitschke

Beilstein J. Org. Chem. 2015, 11, 2350–2354, doi:10.3762/bjoc.11.256

• space, going from a one-dimensional linear array (Figure 1a) [7] to a two-dimensional grid (Figure 1b) [8] to a three-dimensional tetrahedron (Figure 1c) [9], which turned out to be capable of binding white phosphorus (P4) and rendering it air-stable [10]! The work went well at Geneva – we were

Two strategies for the synthesis of the biologically important ATP analogue ApppI, at a multi-milligram scale

• Janne Weisell,
• Jouko Vepsäläinen and
• Petri A. Turhanen

Beilstein J. Org. Chem. 2015, 11, 2189–2193, doi:10.3762/bjoc.11.237

• vacuo. The product 4 (822 mg, 23%) was present as a colorless oil. All NMR data were comparable to those reported elsewhere (except –OCH3 signals which was wrongly interpreted to be two singlets although those protons are coupled to phosphorus) [12]. 1H NMR (CDCl3) 4.84 (s, 1H), 4.77 (s, 1H), 4.16 (vq

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

• phosphines [14][15][16][17][18][19][20][21][22][23]. The most common phosphine, so called “throw-away ligand”, is tricyclohexyl phosphine [10][11][12][13][14][15][16][17][18][19][20][21][22][23]. In other words, such phosphorus donor ligands dissociate from the metal center to afford the 14e− active species

• 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

The enantioselective synthesis of (S)-(+)-mianserin and (S)-(+)-epinastine

• Piotr Roszkowski,
• Jan. K. Maurin and
• Zbigniew Czarnocki

Beilstein J. Org. Chem. 2015, 11, 1509–1513, doi:10.3762/bjoc.11.164

• compounds and their structural analogues. Results and Discussion The synthetic pathway is presented in Scheme 1. The reaction of 2-benzylaniline (3) with N-phthalylglycyl chloride (4) gave amide 5 in 87% yield. The Bischler–Napieralski condensation of amide 5 using phosphorus oxychloride in acetonitrile led

A new method for the synthesis of α-aminoalkylidenebisphosphonates and their asymmetric phosphonyl-phosphinyl and phosphonyl-phosphinoyl analogues

• Anna Kuźnik,
• Roman Mazurkiewicz,
• Mirosława Grymel,
• Katarzyna Zielińska,
• Jakub Adamek,
• Ewa Chmielewska,
• Marta Bochno and
• Sonia Kubica

Beilstein J. Org. Chem. 2015, 11, 1418–1424, doi:10.3762/bjoc.11.153

• acid phosphorus analogues; electrochemical α-methoxylation; 1-phosphinoylalkylphosphonate; 1-phosphinylalkylphosphonate; Introduction α-Aminophosphonic and α-aminophosphinic acids, as phosphorus analogues and bioisosters of α-amino acids, exhibit a variety of important biological properties [1][2][3

• derivatives consist in the consecutive formation of two Cα–P bonds between a carbon electrophile (most often an electrophilic imine intermediate) and two identical molecules of the proper phosphorus nucleophile. Another group of methods requires the formation of a Cα–N bond between an easily accessible

• at low temperature (Scheme 2). The most characteristic feature of the 13C NMR spectra of these compounds was a doublet of doublets in the range of 45–58 ppm (J1 = 42–49 Hz, J2 = 151–160 Hz) assigned to the α-carbon atom coupled with two nonequivalent phosphorus atoms as well as the presence of two

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

• may possess further functionalities in addition to the phosphorus center such as the γ-hydroxypropyl group which results from the ring opening and π-donor moieties such as aryl, allyl, propargyl and allene which originates from the Grignard reagent. Keywords: chirogenic phosphorus; Grignard reagents

• ; oxaphospholanes; phosphinates; phosphine oxides; Introduction Organophosphorus compounds containing phosphorus to carbon bond(s) are widely used in organic transformations. Textbook examples are the Wittig and the Horner–Wadsworth–Emmons reactions. Moreover, the vast majority of ligands used in organometallic

• : (A) Attack by nucleophilic low valent phosphorus compounds (P(III) or phosphide ions P(II)) on positively charged carbon centers (e.g., Michaelis–Arbuzov [7], Michaelis–Becker [8], Pudovik [9], Friedel–Crafts reactions [10], catalytic hydrophosphorylation [11] and others). Notably, these reactions

Advances in the synthesis of functionalised pyrrolotetrathiafulvalenes

• Luke J. O’Driscoll,
• Sissel S. Andersen,
• Marta V. Solano,
• Dan Bendixen,
• Morten Jensen,
• Troels Duedal,
• Jess Lycoops,
• Cornelia van der Pol,
• Rebecca E. Sørensen,
• Karina R. Larsen,
• Kenneth Myntman,
• Christian Henriksen,
• Stinne W. Hansen and
• Jan O. Jeppesen

Beilstein J. Org. Chem. 2015, 11, 1112–1122, doi:10.3762/bjoc.11.125

• sodium borohydride and lithium bromide to 40 g scale, obtaining diol 11 with only a small reduction in yield (77% vs 85% at 15 g scale [33]). Compound 11 is then treated with phosphorus tribromide to afford dibromide 12. The scale up of this reaction to 36 g scale also results in a lower, but still

Diastereoselective and enantioselective conjugate addition reactions utilizing α,β-unsaturated amides and lactams

• Katherine M. Byrd

Beilstein J. Org. Chem. 2015, 11, 530–562, doi:10.3762/bjoc.11.60

• addition reactions where they employed organocopper reagents and chiral phosphorus-based ligands [18]. This breakthrough in the field led to the development of different chiral ligands for asymmetric CA reactions. Another major advancement occurred in 1997 when Feringa’s group developed the first catalytic

Attempts to prepare an all-carbon indigoid system

• Şeref Yildizhan,
• Henning Hopf and
• Peter G. Jones

Beilstein J. Org. Chem. 2015, 11, 363–372, doi:10.3762/bjoc.11.42

• ): representing the basic cross-conjugated π-electron system of the indigoid compounds [7][8][9]. Whereas the replacement of Y in 2 (X = O) by sulfur and selenium [10][11] or even tellurium [12][13] has been known for some time, derivatives of “phosphaindigo” (Y = various substituted phosphorus derivatives) have

An unusually stable chlorophosphite: What makes BIFOP–Cl so robust against hydrolysis?

• Roberto Blanco Trillo,
• Jörg M. Neudörfl and
• Bernd Goldfuss

Beilstein J. Org. Chem. 2015, 11, 313–322, doi:10.3762/bjoc.11.36

• large steric demand of encapsulating fenchane units renders the phosphorus atom nearly inaccessible by nucleophilic reagents, but only for BIFOP–Cl. In addition to the steric effect, a hypervalent P(III)–O interaction as well as an electronic conjugation effect causes the high reactivity of O–BIFOP–Cl

• , in Pd catalysts. Keywords: chirality; hydrolysis; phosphorus; rearrangements; terpenoids; Introduction Phosphorus halides are highly reactive intermediates for the synthesis of phosphites and phosphoramidites [1][2][3][4][5], which are widely used, for example, as ligands in catalysts [6][7][8][9

• analysis of the crystal structure of BIFOP–Cl (1) reveals the large steric demand of the fenchane units, which embed the phosphorus atom, thus making it inaccessible to nucleophilic reagents (Figure 4, Table 1) [14][15]. In contrast, the reduced protection of the phosphorus atom in O-BIFOP-Cl (3), which is

Synthesis of dinucleoside acylphosphonites by phosphonodiamidite chemistry and investigation of phosphorus epimerization

• William H. Hersh

Beilstein J. Org. Chem. 2015, 11, 184–191, doi:10.3762/bjoc.11.19

• corresponding acyl diamidites, RC(O)P(N(iPr)2)2 (R = Me (7), Ph (9)), without the intervention of sodium to give a phosphorus anion. The structure of 9 was confirmed by single-crystal X-ray diffraction. The coupling of the diamidites 7 and 9 with 5′-O-DMTr-thymidine was carried out with N-methylimidazolium

• (albeit not all) antisense reagents, including the two approved drugs, are phosphorothioates, in which one of the terminal oxygen atoms on the phosphodiester internucleotide linker is replaced by sulfur. A potential issue with phosphorothioates is the creation of a new stereocenter at every phosphorus

• P-chiral phosphorothioates, a trivalent dinucleoside phosphorus moiety is required that undergoes rapid epimerization under the sulfurization conditions – that is, the goal was to carry out a dynamic kinetic resolution with formation of a single epimeric phosphorothioate. In order to carry out the