Thermotropic and lyotropic behaviour of new liquid-crystalline materials with different hydrophilic groups: synthesis and mesomorphic properties

• Alexej Bubnov,
• Miroslav Kašpar,
• Věra Hamplová,
• Ute Dawin and
• Frank Giesselmann

Beilstein J. Org. Chem. 2013, 9, 425–436, doi:10.3762/bjoc.9.45

• a yellow viscous liquid of TEG-tosylate. 1H NMR (CDCl3, 300 MHz) for the intermediate product TEG-tosylate δ (ppm) 7.72 (d, 2H, ortho to SO3), 7.30 (d, 2H, ortho to CH3), 4.10 (t, 2H, CH2OAr), 3.65–3.45 (m, 14H, CH2O), 3.30 (s, 3H, CH3O), 2.38 (s, 3H, CH3Ar). A mixture of 68 g (0.188 mol) of TEG

• –tosylate and 38 g (0.2 mol) of 4,4‘-biphenol was dissolved in 0.5 L ethanol/water (1:1) and heated under reflux. Sodium hydroxide (12 g) dissolved in 50 mL of water was added drop by drop over several hours. Boiling under reflux was continued for 4 days, the solution was then acidified with hydrochloric

Spin state switching in iron coordination compounds

• Philipp Gütlich,
• Ana B. Gaspar and
• Yann Garcia

Beilstein J. Org. Chem. 2013, 9, 342–391, doi:10.3762/bjoc.9.39

A new approach toward the total synthesis of (+)-batzellaside B

• Jolanta Wierzejska,
• Shin-ichi Motogoe,
• Yuto Makino,
• Tetsuya Sengoku,
• Masaki Takahashi and
• Hidemi Yoda

Beilstein J. Org. Chem. 2012, 8, 1831–1838, doi:10.3762/bjoc.8.210

• with TsCl in the presence of pyridine was carried out to yield the corresponding tosylate, whose activated ester group could be displaced with NaCN in DMSO to provide cyanide 15 in 80% yield over three steps [43]. Then, the N,O-acetonide group of 15 was cleaved upon treatment with p-TsOH in methanol

Two-directional synthesis as a tool for diversity-oriented synthesis: Synthesis of alkaloid scaffolds

• Kieron M. G. O’Connell,
• Monica Díaz-Gavilán,
• Warren R. J. D. Galloway and
• David R. Spring

Beilstein J. Org. Chem. 2012, 8, 850–860, doi:10.3762/bjoc.8.95

• intramolecular conjugate addition. Three of these compounds (1–3) were obtained from the corresponding alcohols [19][20] in three steps: Mitsunobu reaction with NH-Boc-tosylate, followed by tosyl deprotection with magnesium, and finally two-directional cross metathesis with ethyl acrylate to install the desired

An easy α-glycosylation methodology for the synthesis and stereochemistry of mycoplasma α-glycolipid antigens

• Yoshihiro Nishida,
• Yuko Shingu,
• Yuan Mengfei,
• Kazuo Fukuda,
• Hirofumi Dohi,
• Sachie Matsuda and
• Kazuhiro Matsuda

Beilstein J. Org. Chem. 2012, 8, 629–639, doi:10.3762/bjoc.8.70

• phosphocholine group at the sugar 6-OH position, we employed a phosphoroamidite method using 1H-tetrazole as a promoter [34]. First, 8a was treated with 2-cyanoethyl-N,N,N’,N’-tetraisopropyl phosphorodiamidite in the presence of 1H-tetrazole, and then with choline tosylate to give 9a. After removal of the sugar

• phosphorodiamidite (90.4 mg, 0.30 mmol) in 10 mL of CH2Cl2 was injected. 1H-tetrazole (28.4 mg, 0.40 mmol) was added and stirred for 2 h at rt. Then 1H-tetrazole (42.6 mg, 0.60 mmol, 3.0 equiv) and choline tosylate (220.3 mg, 0.8 mmol: thoroughly dried overnight under vacuum) were added to the reaction mixture and

• tosylate, 1H-tetrazole, (iii) mCPBA, (iv) aq. NH3 in CH3OH, (f) H2, Pd(OH)2/C in CH3OH. 1H NMR data (500 MHz) of I-a, I-b, and their precursors (9a and 9b). Acknowledgements This work was supported by the Industrial Technology Research Grant Program from New Energy and Industrial Technology Development

Reduction of benzylic alcohols and α-hydroxycarbonyl compounds by hydriodic acid in a biphasic reaction medium

• Michael Dobmeier,
• Josef M. Herrmann,
• Dieter Lenoir and
• Burkhard König

Beilstein J. Org. Chem. 2012, 8, 330–336, doi:10.3762/bjoc.8.36

• complexes [9][10][11][12][13]. Most procedures require a sequence of steps, e.g., the conversion of hydroxy groups into a chloride or bromide substituent and subsequent catalytic reduction with H2/Pt or the conversion into a tosylate and reduction with LiAlH4. The most commonly applied method is the Barton

Fifty years of oxacalix[3]arenes: A review

• Kevin Cottet,
• Paula M. Marcos and
• Peter J. Cragg

Beilstein J. Org. Chem. 2012, 8, 201–226, doi:10.3762/bjoc.8.22

Efficient, highly diastereoselective MS 4 Å-promoted one-pot, three-component synthesis of 2,6-disubstituted-4-tosyloxytetrahydropyrans via Prins cyclization

• Naseem Ahmed and
• Naveen Kumar Konduru

Beilstein J. Org. Chem. 2012, 8, 177–185, doi:10.3762/bjoc.8.19

• transfer to the hydroxy group. Then, a nucleophilic attack of PTSA resulted in α-tosyloxyether formation after losing a water molecule. In the α-tosyloxyether, the delocalization of lone-pair electrons on the oxygen atom led to the removal of the tosylate group and oxo-carbenium ion intermediate formation

• . Then, an intramolecular nucleophilic attack of the double bond in the oxo-carbenium ion led to cyclization and charge transfer complex formation with the tosylate group to afford the 2,6-disubstituted-4-tosyloxytetrahydropyran (Scheme 2). All structures of the 2,6-disubstituted-4

Synthetic approaches to multifunctional indenes

• Neus Mesquida,
• Sara López-Pérez,
• Immaculada Dinarès and
• Ermitas Alcalde

Beilstein J. Org. Chem. 2011, 7, 1739–1744, doi:10.3762/bjoc.7.204

• in which the (3-indenyl)acetic acid 7 was reduced to the corresponding alcohol 10 and transformed to tosylate 11. However, an attempt to convert the (3-indenyl)ethylsulfonate 11 into the advanced inden-5-amine 9 was ineffective, resulting in the formation of the spiro indene 12 instead, and hence

Recent advances in direct C–H arylation: Methodology, selectivity and mechanism in oxazole series

• Cécile Verrier,
• Pierrik Lassalas,
• Laure Théveau,
• Guy Quéguiner,
• François Trécourt,
• Francis Marsais and
• Christophe Hoarau

Beilstein J. Org. Chem. 2011, 7, 1584–1601, doi:10.3762/bjoc.7.187

• direct arylation of (benz)oxazoles with (pseudo)halides, carboxyarenes and organometallics Ackermann was the first to find convenient conditions for the base-assisted, Pd(0)-catalyzed direct substitutive coupling of heteroarene applicable to tosylate and mesylate electrophiles, which are prepared from

Highly efficient cyclosarin degradation mediated by a β-cyclodextrin derivative containing an oxime-derived substituent

• Michael Zengerle,
• Florian Brandhuber,
• Christian Schneider,
• Franz Worek,
• Georg Reiter and
• Stefan Kubik

Beilstein J. Org. Chem. 2011, 7, 1543–1554, doi:10.3762/bjoc.7.182

• ). Cyclodextrin derivatives tested as potential GF scavengers. General strategies used for the preparation of the investigated cyclodextrin derivatives. Reaction conditions used for the preparation of cyclodextrin derivatives 1a–e from tosylate 3. Synthesis of 3-(aminomethyl)benzaldehyde oxime (5). Reagents and

Synthesis and oxidation of some azole-containing thioethers

• Andrei S. Potapov,
• Nina P. Chernova,
• Vladimir D. Ogorodnikov,
• Tatiana V. Petrenko and
• Andrei I. Khlebnikov

Beilstein J. Org. Chem. 2011, 7, 1526–1532, doi:10.3762/bjoc.7.179

• -dimethylpyrazole and fully characterized the thioether for the first time [13]. We found that the use of freshly recrystallized Na2S·9H2O in the reaction with 1-(2-hydroxyethyl)-3,5-dimethylpyrazole tosylate (2) yields a solid product in good yield. We also prepared a pyrazole-containing thioether 4 with two

• sulfur atoms by the reaction of tosylate 2 with 1,2-ethanedithiolate formed in situ from diisothiuroium salt of 1,2-dibromoethane (Scheme 2). The proposed method of synthesis has an advantage over the previously reported one [8], since it does not involve the use of odoriferous and unstable 1,2

A new phenylethyl alkyl amide from the Ambrostoma quadriimpressum Motschulsky

• Guolei Zhao,
• Chao Yang,
• Bing Li and
• Wujiong Xia

Beilstein J. Org. Chem. 2011, 7, 1342–1346, doi:10.3762/bjoc.7.158

• -heptylidenetriphenylphosphonium bromide in the presence of n-BuLi gave adduct 11 as an (E/Z)-mixture (E/Z = 1:5) in 75% yield. Selective removal of the TBS group with pyridinium tosylate gave 12 in 98% yield [21]. With the alcohol 12 in hand, our next step was to synthesize the phosphonium salt 15 [22][23] (Scheme 4). Therefore

Recent advances in the gold-catalyzed additions to C–C multiple bonds

• He Huang,
• Yu Zhou and
• Hong Liu

Beilstein J. Org. Chem. 2011, 7, 897–936, doi:10.3762/bjoc.7.103

• the tosylate followed by the interaction with the imine and a Nazarov-like cyclization. Barluenga et al. reported a gold-catalyzed cascade reaction involving an unusual intramolecular redox process in which 5-heteroaryl-substituted ketone derivatives 372 were obtained from secondary 5-hexyn-1-ols 370

Isotopic labelling studies for a gold-catalysed skeletal rearrangement of alkynyl aziridines

• Paul W. Davies,
• Nicolas Martin and
• Neil Spencer

Beilstein J. Org. Chem. 2011, 7, 839–846, doi:10.3762/bjoc.7.96

• -disubstituted products could be achieved in quantitative yields when the counter ion was the more basic tosylate [19]. Alternatively, the use of protic, ethereal or aromatic solvents favoured the formation of the 2,5-disubstituted products regardless of the counter ion. Similar solvent regimes were employed in

Reciprocal polyhedra and the Euler relationship: cage hydrocarbons, C_nH_n and closo-boranes [B_xH_x]²⁻

• Michael J. McGlinchey and
• Henning Hopf

Beilstein J. Org. Chem. 2011, 7, 222–233, doi:10.3762/bjoc.7.30

• manipulation led to the iodo-tosylate 39 which, in the presence of base, generated the homohypostrophene, 40; [2 + 2] cycloaddition then furnished the homopentaprismanone 41. Introduction of a bridge head bromine (with the intent of carrying out a Favorskii ring contraction) proved to be impossible. Instead it

Ene–yne cross-metathesis with ruthenium carbene catalysts

• Cédric Fischmeister and
• Christian Bruneau

Beilstein J. Org. Chem. 2011, 7, 156–166, doi:10.3762/bjoc.7.22

• ][76] were prepared. One-pot EYCM followed by Brønsted acid catalyzed cyclization enabled the formation of monounsaturated cyclic amines [77]. The EYCM of homopropargylic tosylate with allylic alcohol derivatives has been used as a key step for the construction of the side chain of mycothiazole [78

Carbasugar analogues of galactofuranosides: α-O-linked derivatives

• Jens Frigell and
• Ian Cumpstey

Beilstein J. Org. Chem. 2010, 6, 1127–1131, doi:10.3762/bjoc.6.129

• were observed and were not isolated in a pure form. The free OH-2 could then be converted to its tosylate 7. Treatment of this diester 7 with sodium methoxide resulted in the direct formation of the required epoxide 4, presumably by cleavage of the C1 benzoate to the alcoholate (with retention of

• configuration) followed by intramolecular displacement of the C2 tosylate (with inversion of configuration). We synthesised the same epoxide 4 (78%) by treatment of isolated 3,5,6-tri-O-benzyl-2-O-(toluene-4-sulfonyl)-4a-carba-β-D-galactofuranose [9] with sodium hydride in DMF. We investigated ring-opening of

β-Hydroxy carbocation intermediates in solvolyses of di- and tetra-hydronaphthalene substrates

• Jaya S. Kudavalli and
• Rory A. More O'Ferrall

Beilstein J. Org. Chem. 2010, 6, 1035–1042, doi:10.3762/bjoc.6.118

• . Surprisingly, while the solvolysis of trans-2-methoxycyclohexyl tosylate has been well studied [17], there appear to have been no measurements reported for its cis isomer. We cannot compare these rate ratios directly with those for the solvolyses of cis- and trans-1-trichloroacetoxy-2

Synthesis and crystal structures of multifunctional tosylates as basis for star-shaped poly(2-ethyl-2-oxazoline)s

• Richard Hoogenboom,
• Martin W. M. Fijten,
• Guido Kickelbick and
• Ulrich S. Schubert

Beilstein J. Org. Chem. 2010, 6, 773–783, doi:10.3762/bjoc.6.96

• -oxazolines resulting in star-shaped polymers. The synthesis of the tosylates was performed by esterification of the corresponding alcohols with tosyl chloride. Recrystallization of these tosylate compounds afforded single crystals, and the X-ray crystal structures of di-, tetra- and hexa-tosylates are

• reported. The use of tetra- and hexa-tosylates, based on (di)pentaerythritol as initiators for the CROP of 2-ethyl-2-oxazoline, resulted in very slow initiation and ill-defined polymers, which is most likely caused by steric hindrance in these initiators. As a consequence, a porphyrin-cored tetra-tosylate

• initiator was prepared, which yielded a well-defined star-shaped poly(2-ethyl-2-oxazoline) by CROP as demonstrated by SEC with RI, UV and diode-array detectors, as well as by 1H NMR spectroscopy. Keywords: cationic polymerization; crystal structure; living polymerization; star-polymer; tosylate

Synthesis and crystallographic analysis of meso-2,3-difluoro-1,4-butanediol and meso-1,4-dibenzyloxy-2,3-difluorobutane

• Bruno Linclau,
• Leo Leung,
• Jean Nonnenmacher and
• Graham Tizzard

Beilstein J. Org. Chem. 2010, 6, No. 62, doi:10.3762/bjoc.6.62

• 3 as a building block, in particular for the construction of longer aliphatic chains of varying length, was investigated next. Thus (Scheme 2), the diol moiety in 3 was monoprotected as a silyl ether, and the remaining alcohol group was activated as the corresponding tosylate 9, triflate 10

New amphiphilic glycopolymers by click functionalization of random copolymers – application to the colloidal stabilisation of polymer nanoparticles and their interaction with concanavalin A lectin

• Otman Otman,
• Paul Boullanger,
• Eric Drockenmuller and
• Thierry Hamaide

Beilstein J. Org. Chem. 2010, 6, No. 58, doi:10.3762/bjoc.6.58

• were difficult to separate from the desired compounds. The addition of triethylene glycol derivatives was also attempted by coupling triethylene glycol, or an activated triethylene glycol derivative bearing a tosylate or a chlorine atom at the ω-position. This latter approach proved to be better. The

Synthesis of lipophilic 1-deoxygalactonojirimycin derivatives as D-galactosidase inhibitors

• Georg Schitter,
• Elisabeth Scheucher,
• Andreas J. Steiner,
• Arnold E. Stütz,
• Martin Thonhofer,
• Chris A. Tarling,
• Stephen G. Withers,
• Jacqueline Wicki,
• Katrin Fantur,
• Eduard Paschke,
• Don J. Mahuran,
• Brigitte A. Rigat,
• Michael Tropak and
• Tanja M. Wrodnigg

Beilstein J. Org. Chem. 2010, 6, No. 21, doi:10.3762/bjoc.6.21

• % yield by ring nitrogen alkylation with tosylate 21 (Scheme 5) [43]. Inhibition constants of the compounds synthesised are presented in Table 1. The 1-deoxygalactonojirimycin analogues were tested as inhibitors of Agrobacterium sp. β-glucosidase/galactosidase and E. coli β-galactosidase as well as green

Three step synthesis of single diastereoisomers of the vicinal trifluoro motif

• Vincent A. Brunet,
• Alexandra M. Z. Slawin and
• David O'Hagan

Beilstein J. Org. Chem. 2009, 5, No. 61, doi:10.3762/bjoc.5.61

• the requisite α,β-epoxy alcohols 6b and 7b. Three step sequential fluorination from α,β-epoxy alcohols to eg. the vicinyltrifluoro tosylate 11. Unexpected cyclisation of 9b to furan 14 with HF·pyridine. An X-ray structure of 14 (CCDC 750309) reveals that the cyclisation proceeds with a retention of

• configuration. Epoxide ring opening of 9b with 3HF·Et3N required forcing conditions. The structure and stereochemistry 12b (CCDC 750308) and 16 (CCDC 750310) was established by X-ray analysis. Three step sequential fluorination from α,β-epoxy alcohol 7b to vicinal trifluoro tosylate 17b. Epoxide ring opening

• with 3HF∙Et3N and synthesis of the all-syn vicinal trifluoro tosylate 17a. Reaction of α,β-epoxy alcohol 7a and 7b under various fluorination conditions. Ratios determined by 19F NMR. Supporting Information Supporting Information File 80: Experimental methods and full characterisation and spectral

Synthesis of mesogenic phthalocyanine-C₆₀ donor–acceptor dyads designed for molecular heterojunction photovoltaic devices

• Yves Henri Geerts,
• Olivier Debever,
• Claire Amato and
• Sergey Sergeyev

Beilstein J. Org. Chem. 2009, 5, No. 49, doi:10.3762/bjoc.5.49

• modest yields of 10a–d actually correspond to those reported earlier for other A3B-type phthalocyanines: yields higher than 20% are rare in such reactions [45][49][50][51]. The MEM protective group in 10a–d was then quantitatively removed to give 4a–d upon treatment with pyridinium tosylate (PPTS) in t