Flow synthesis of phenylserine using threonine aldolase immobilized on Eupergit support

• Jagdish D. Tibhe,
• Hui Fu,
• Timothy Noël,
• Qi Wang,
• Jan Meuldijk and
• Volker Hessel

Beilstein J. Org. Chem. 2013, 9, 2168–2179, doi:10.3762/bjoc.9.254

• acrylic beads provide a rapid and simple support for immobilization and have been used to immobilize various enzymes for a number of reactions [46]. Immobilization on Eupergit (a porous material) can be achieved without the need for any additional reagents, as the epoxy groups on Eupergit can react

• directly with the nucleophilic groups of the enzyme by forming strong covalent linkages like amino, hydroxy or mercapto functional groups. Eupergit has a high density of epoxy groups on the surface (oxirane density 300 μmol/g dry beads [47]), increasing the possibility of multipoint attachment of the

• each other which resulted in higher values for enzyme retention. For the indirect method, however, the epoxy groups were converted into aldehyde groups. These groups can only react with nucleophiles such as amino groups. During treatment of Eupergit with ethylenediamine, a coupling of two adjacent

A concise enantioselective synthesis of the guaiane sesquiterpene (−)-oxyphyllol

• Martin Zahel and
• Peter Metz

Beilstein J. Org. Chem. 2013, 9, 2028–2032, doi:10.3762/bjoc.9.239

• Martin Zahel Peter Metz Fachrichtung Chemie und Lebensmittelchemie, Organische Chemie I, Technische Universität Dresden, Bergstrasse 66, 01069 Dresden, Germany 10.3762/bjoc.9.239 Abstract (−)-Oxyphyllol was prepared in only 4 steps from an epoxy enone that already served as an intermediate for

• 3 can be utilized to generate the isopropyl group, and a regioselective transannular epoxide opening would construct the oxygen-bridged bicyclic hydroazulene framework. Alcohol 3 was traced back to the known epoxy enone 4 that already served as an intermediate for the total synthesis of 5 [6]. As

Exploration of an epoxidation–ring-opening strategy for the synthesis of lyconadin A and discovery of an unexpected Payne rearrangement

• Brad M. Loertscher,
• Yu Zhang and
• Steven L. Castle

Beilstein J. Org. Chem. 2013, 9, 1179–1184, doi:10.3762/bjoc.9.132

• complex [29] at the less-hindered carbon of the epoxide would provide 26. Acid- and Lewis acid promoted Payne rearrangements of epoxy alcohols [33][34] and epoxy methyl ethers [35] have been described, but we are unaware of any prior reports of Payne rearrangements of the bulkier epoxy trityl ethers

Efficient regio- and stereoselective access to novel fluorinated β-aminocyclohexanecarboxylates

• Loránd Kiss,
• Melinda Nonn,
• Reijo Sillanpää,
• Santos Fustero and
• Ferenc Fülöp

Beilstein J. Org. Chem. 2013, 9, 1164–1169, doi:10.3762/bjoc.9.130

• bond oxidation with 3-chloroperbenzoic acid (MCPBA) to afford epoxy amino ester 6 cis-diastereoselectively [57] (Scheme 1). Opening of the oxirane ring in 6 with NaBH4 in EtOH at 70 °C proceeded regioselectively, providing exclusively amino ester 5 with the hydroxy function on position 4 (for analogous

Facile synthesis of functionalized spiro[indoline-3,2'-oxiran]-2-ones by Darzens reaction

• Qin Fu and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2013, 9, 918–924, doi:10.3762/bjoc.9.105

• . The 1H NMR spectra of compounds 3a–h and 4a–e usually show one set of characteristic peaks for each group, especially one singlet at about 5.10 ppm for one proton of the epoxy unit, which clearly indicates that only one isomer exists in each sample. However, 1H NMR spectra of compounds 3a and 3f

• ratios. It is known that the closure of the epoxy ring would form cis/trans isomers in the Darzens reaction process. Here the N-benzyl and the N-butyl group in the oxindole moiety may decrease the steric effect of formation of the epoxy ring and lead to the easier formation of the relatively unstable cis

New core-pyrene π structure organophotocatalysts usable as highly efficient photoinitiators

• Sofia Telitel,
• Frédéric Dumur,
• Thomas Faury,
• Bernadette Graff,
• Mohamad-Ali Tehfe,
• Didier Gigmes,
• Jean-Pierre Fouassier and
• Jacques Lalevée

Beilstein J. Org. Chem. 2013, 9, 877–890, doi:10.3762/bjoc.9.101

• of the epoxy content was also continuously followed by real-time FTIR spectroscopy (FTIR NEXUS 870). A Xe–Hg lamp (Hamamatsu, L8252, 150 W, filtered light at λ > 340 nm; intensity ~ 30 mW/cm²) and a halogen lamp (intensity ~10 mW/cm²; the emission spectrum is given in [43]) were used as the

Asymmetric total synthesis of smyrindiol employing an organocatalytic aldol key step

• Dieter Enders,
• Jeanne Fronert,
• Tom Bisschops and
• Florian Boeck

Beilstein J. Org. Chem. 2012, 8, 1112–1117, doi:10.3762/bjoc.8.123

• ). A few years later Snider et al. described the, up to now, sole total synthesis of smyrindiol using an enantiomerically pure epoxy aldehyde [9]. The two possible diastereoisomers resulting from the addition of the epoxy aldehyde to the coumaryl Grignard intermediate, occurred with low

Synthesis of a library of tricyclic azepinoisoindolinones

• Bettina Miller,
• Shuli Mao,
• Kara M. George Rosenker,
• Joshua G. Pierce and
• Peter Wipf

Beilstein J. Org. Chem. 2012, 8, 1091–1097, doi:10.3762/bjoc.8.120

• . When the RCM reaction of 7 was conducted on larger scale in the absence of Ti(OiPr)4, and the crude intermediate was subjected to m-CPBA oxidation, epoxy alcohol 6 was isolated in 11% overall yield. LC–MS as well as NMR analyses suggested a 5:1 ratio of epimers at the hemiacetal carbon. Hydroxylation

Unprecedented deoxygenation at C-7 of the ansamitocin core during mutasynthetic biotransformations

• Tobias Knobloch,
• Gerald Dräger,
• Wera Collisi,
• Florenz Sasse and
• Andreas Kirschning

Beilstein J. Org. Chem. 2012, 8, 861–869, doi:10.3762/bjoc.8.96

• produces the expected ansamitocin derivative 14 in good yield (Scheme 4) [28]. Besides the ester side chain, compound 14 also lacks the epoxy functionality and the N-methyl group. These two tailoring steps finalize the biosynthesis of ansamitocin P-3 (AP-3, 4) and occur only after acylation has taken place

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

• -glycosyl bromide species [32]. In the pathway using DMF, the α-glycosylation is routed via α-glycosyl cationic imidate 3, which was predicted in former studies [33] and evidenced in our preceding NMR and MS study [25][26]. The reaction between 1 and (S)-glycidol in CH2Cl2 (+ TMU) gave a mixture of epoxy

Intramolecular carbenoid ylide forming reactions of 2-diazo-3-keto-4-phthalimidocarboxylic esters derived from methionine and cysteine

• Marc Enßle,
• Stefan Buck,
• Roland Werz and
• Gerhard Maas

Beilstein J. Org. Chem. 2012, 8, 433–440, doi:10.3762/bjoc.8.49

• . Characteristics are the signals for the NCH proton (13a: δ = 4.60 ppm; 13b: δ = 4.67 ppm) and the two bridgehead carbons of the epoxy bridge (13a: δ = 86.60 and 94.13 ppm; 13b: δ = 86.75 and 94.04 ppm). While a CI mass spectrum of 13b showed a weak molecular-ion peak for the dimer (the base peak representing the

• monomer unit), in the case of 13a, even under these mild conditions of chemical ionisation, the spectrum showed no peak at m/z greater than that for the monomer, which was again the base peak. The relative stereochemistry shown in Scheme 4, with the two epoxy bridges in syn relationship and the

Improved syntheses of high hole mobility phthalocyanines: A case of steric assistance in the cyclo-oligomerisation of phthalonitriles

• Daniel J. Tate,
• Rémi Anémian,
• Richard J. Bushby,
• Suwat Nanan,
• Stuart L. Warriner and
• and Benjamin J. Whitaker

Beilstein J. Org. Chem. 2012, 8, 120–128, doi:10.3762/bjoc.8.14

• calibrated with indium (mp 156.60, ΔH = 28.53 J·g−1) and a heating/cooling rate of 10 °C·min−1. Time-of-flight photoconductivity studies The cells were assembled in a laminar-flow hood to avoid contamination by dust or grease. Each ITO-coated glass slide was connected to a copper wire by epoxy resin (Aradite

• ) and the tip of the wire was bonded to the ITO surface with silver paint (RS 186-3600). The two halves were separated by a PET spacer (Goodfellow Cambridge Limited) with a thickness of 23 μm, held in position with clips and secured with epoxy resin. The thickness of the cell (d) was accurately

Imidazole as a parent π-conjugated backbone in charge-transfer chromophores

• Jiří Kulhánek and
• Filip Bureš

Beilstein J. Org. Chem. 2012, 8, 25–49, doi:10.3762/bjoc.8.4

• and co-workers reported the synthesis of epoxy-based nonlinear optical polymers 144 functionalized by post-azo coupling (Figure 23; [130]). The parent polymer backbone was synthesized from diglycidyl ether of bisphenol A and aniline and was further functionalized by diazotized amine 83 (Figure 15

• -functionalized chromophores incorporated into a polymer backbone Rpol [18][50][51][52][53][122][123][124]. Structure of polyphosphazene polymers bearing NLO-phores [125][126][127] and some other recent examples of nonlinear optical polymers [19][128]. Epoxy- and silica-based polymers functionalized with 4,5

A practical microreactor for electrochemistry in flow

• Kevin Watts,
• William Gattrell and
• Thomas Wirth

Beilstein J. Org. Chem. 2011, 7, 1108–1114, doi:10.3762/bjoc.7.127

• without any added electrolyte [4][5]. Atobe et al. constructed a thin layer flow cell from platinum and/or glassy carbon plates (3 × 3 cm), separated by adhesive tape (80 µm), with a space left in between to act as the channel, and the devices were sealed with epoxy resin [6]. They reported the self

Functionalization of anthracene: A selective route to brominated 1,4-anthraquinones

• Kiymet Berkil Akar,
• Osman Cakmak,
• Orhan Büyükgüngör and
• Ertan Sahin

Beilstein J. Org. Chem. 2011, 7, 1036–1045, doi:10.3762/bjoc.7.118

• structure of tetralin oxide 26 produced from the corresponding halohydrine 25, shows the existence of hydrogen bonding between the hydroxy and the epoxy group, which has the same stereochemistry as that of compound 5 [1][14][15]. Thus, the fact that compound 23 was not obtained from 17 can be attributed to

Synthetic applications of gold-catalyzed ring expansions

• David Garayalde and
• Cristina Nevado

Beilstein J. Org. Chem. 2011, 7, 767–780, doi:10.3762/bjoc.7.87

• . Acyloxylated alkynyl oxiranes 28 and 30 have also proved to be versatile building blocks for the synthesis of divinyl ketones 29 [29], 2,5-disubstituted furans 31 [30] and difurylmethane derivatives 32 [31], respectively (Scheme 10). Epoxy alkynes can also be transformed with high stereoselectivity into ketals

Metathesis access to monocyclic iminocyclitol-based therapeutic agents

• Ileana Dragutan,
• Valerian Dragutan,
• Carmen Mitan,
• Hermanus C.M. Vosloo,
• Lionel Delaude and
• Albert Demonceau

Beilstein J. Org. Chem. 2011, 7, 699–716, doi:10.3762/bjoc.7.81

• tetrahydropyridine scaffold 72 allowed an efficient synthesis of 1-deoxynojirimycin 62, and its stereoisomers 65 and 66. Thus, acid hydrolysis of the epoxy ring in the anti isomer 73 (H2SO4/dioxane/H2O, 0.2:3:2) gave 1-deoxynojirimycin (62) and 1-deoxyaltronojirimycin (65) in a 1:1 ratio and in 89% yield. Conversely

• modified Upjohn conditions, Scheme 22). For iminocyclitols containing trans diols at the 3- and 4-positions an epoxy functionality at the double bond in 125 was introduced. While the syn epoxide 128 led to a mixture of fagomine (129) and 3,4-di-epi-fagomine (130), the anti epoxide 127 gave 129 selectively

Highly substituted benzannulated cyclooctanol derivatives by samarium diiodide-induced cyclizations

• Jakub Saadi,
• Irene Brüdgam and
• Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2010, 6, 1229–1245, doi:10.3762/bjoc.6.141

Miniemulsion polymerization as a versatile tool for the synthesis of functionalized polymers

• Daniel Crespy and
• Katharina Landfester

Beilstein J. Org. Chem. 2010, 6, 1132–1148, doi:10.3762/bjoc.6.130

• probably yield polymer particles with a bimodal size distribution. The first polyadditions in miniemulsion carried out were the reactions of polyepoxides and hydrophobic diamines, bisphenols, and dimercaptans [11]. Stable latexes of epoxy resins could be obtained and apparent molecular weights up to 20,000

• variety of polymers, e.g., with epoxy, polyurethane (Figure 7), and polyurea, or based on synthetic polyamines, polythiourea, crosslinked starch, dextran or polyethylene imine [116]. Therefore, the functionality can be directly implemented in the capsules by using an excess of one of the monomers, or by

Synthesis, characterization and photoinduced curing of polysulfones with (meth)acrylate functionalities

• Cemil Dizman,
• Sahin Ates,
• Lokman Torun and
• Yusuf Yagci

Beilstein J. Org. Chem. 2010, 6, No. 56, doi:10.3762/bjoc.6.56

• after polymerization. The second involves direct copolymerization of functionalized monomers [4][5][6]. An increasing topic of interest concerns cooperation of PSUs with epoxy resins via end group functionalization or blending. Engineering thermoplastics based on PSU have been widely used to overcome

• the problems associated with the brittleness of epoxy resins [7][8][9][10][11]. Telechelic oligomers are defined as the prepolymers carrying one or more functional end groups. They take part in further polymerization or other reactions through their functional end groups [12]. The functionality of the

Ring opening metathesis polymerization-derived block copolymers bearing chelating ligands: synthesis, metal immobilization and use in hydroformylation under micellar conditions

• Gajanan M. Pawar,
• Jochen Weckesser,
• Siegfried Blechert and
• Michael R. Buchmeiser

Beilstein J. Org. Chem. 2010, 6, No. 28, doi:10.3762/bjoc.6.28

• -3,6-Epoxy-1,2,3,6-tetrahydrophtalic anhydride (10.0 g, 60.0 mmol), 2-dimethylaminoethanol (6.3 mL, 62.0 mmol, 1.03 equiv) and p-toluenesulfonic acid (590 mg, 3.1 mmol, 5 mol%) were dissolved in 120 mL of THF and stirred at room temperature for 8 h. The white precipitate was filtered, washed with

Diastereoselective functionalisation of benzo-annulated bicyclic sultams: Application for the synthesis of cis-2,4-diarylpyrrolidines

• Susan Kelleher,
• Pierre-Yves Quesne and
• Paul Evans

Beilstein J. Org. Chem. 2009, 5, No. 69, doi:10.3762/bjoc.5.69

• dependent on the electronic nature of the aryl motif and of the reaction solvent. Experimental Representative experimental procedures are shown for compounds 7a, 13a, 18b, 24a, 27, 31, 35, 39. For full experimental details see accompanying Supporting Information. (±)-(1S,10R,11R)-Epoxy-8-thia-9-azatricyclo

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

• described. The route starts from either syn- or anti-α,β-epoxy alcohols and takes a direct approach in that each of the three steps introduces a fluorine atom in a regio- and stereo-specific manner. Starting from either the syn- or the anti-α,β-epoxy alcohol, stereospecific reactions generate two separate

• practical route to this class of compounds is required if these vicinal trifluoro motifs are to be applied usefully. A three step strategy, as illustrated in Scheme 2, starting from diastereoisomeric syn- or anti-α,β-epoxy alcohols A was envisaged, each step incorporating a fluorine atom in a stereospecific

• reactions following Sharpless’ methodology [16]. The anti-epoxy alcohols were easily generated, however it proved more difficult to prepare the syn-epoxides cleanly. Treatment with titanium isopropoxide (Ti(OiPr)4) and D-diisopropyl tartrate (D-DIPT) favoured formation of the anti-α,β-epoxy alcohols. In the

The development and evaluation of a continuous flow process for the lipase- mediated oxidation of alkenes

• Charlotte Wiles,
• Marcus J. Hammond and
• Paul Watts

Beilstein J. Org. Chem. 2009, 5, No. 27, doi:10.3762/bjoc.5.27

• ), 97 (77), 85 (15), 95 (100), 83 (15), 69 (15) and 55 (25); GC-MS tR = 5.26 min. The spectroscopic data obtained for 1-methylcyclohexene oxide (7) was consistent with that reported within the literature [36]. 1,2-Epoxy-1-phenylethane (styrene oxide) A pre-mixed solution containing styrene (9, 0.1 M

• -epoxy-1-phenylethane as a colourless oil (0.086 g, 99.2% yield); 1H NMR (400 MHz, CDCl3) δ 2.75 (dd, J = 2.8, 5.6, 1H), 3.08 (dd, J = 4.1, 5.6, 1H), 3.80 (dd, J = 2.8, 4.1, 1H) and 7.24–7.33 (m, 5H); 13C NMR (100 MHz, CDCl3) δ 51.0 (CH2), 51.1 (CH), 125.3 (2 × CH), 128.0 (CH), 128.2 (2 × CH) and 137.5

• (C); m/z (EI) 121 (M++1, 5%), 120 (20), 119 (50), 92 (25), 91 (100), 89 (40) and 77 (20); GC-MS tR = 5.37 min. The spectroscopic data obtained for 1,2-epoxy-1-phenylethane was consistent with that reported within the literature [37]. cis-1,2-Diphenyloxirane (cis-stilbene oxide, 13) A solution

A short stereoselective synthesis of (+)-(6R,2′S)-cryptocaryalactone via ring- closing metathesis

• Palakodety Radha Krishna,
• Krishnarao Lopinti and
• K. L. N. Reddy

Beilstein J. Org. Chem. 2009, 5, No. 14, doi:10.3762/bjoc.5.14

• alcohol that was obtained from a regioselective ring-opening reaction of 2,3-epoxy alcohol 8. The known 2,3-epoxy alcohol 8 was synthesized from the corresponding dienyl alcohol by the well-established Sharpless asymmetric epoxidation conditions in >94% ee as described in literature [38][39]. Compound 8

• wherein a chiral 2,3-epoxy alcohol was the starting material and Sharpless asymmetric epoxidation and Carreira asymmetric alkynylation were used as key steps for generating unambiguous assigned stereocenters. More importantly, the Grubbs’ ring-closing metathesis protocol was applied to construct the final