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Search for "sulfone" in Full Text gives 115 result(s) in Beilstein Journal of Organic Chemistry.

Opportunities and challenges for direct C–H functionalization of piperazines

  • Zhishi Ye,
  • Kristen E. Gettys and
  • Mingji Dai

Beilstein J. Org. Chem. 2016, 12, 702–715, doi:10.3762/bjoc.12.70

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  • % yield with Ir(ppy)3 as the catalyst [63]. In another report, MacMillan et al. showed that under similar photoredox conditions, 87 could couple with vinyl sulfone 90 to provide α-vinylation product 91 in 74% yield with excellent E/Z selectivity [65]. They also discovered that piperazine 87 could couple
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Published 13 Apr 2016

Facile synthesis of 4H-chromene derivatives via base-mediated annulation of ortho-hydroxychalcones and 2-bromoallyl sulfones

  • Srinivas Thadkapally,
  • Athira C. Kunjachan and
  • Rajeev S. Menon

Beilstein J. Org. Chem. 2016, 12, 16–21, doi:10.3762/bjoc.12.3

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  • that such problems may be circumvented by developing a synthetic surrogate for the sensitive allenyl sulfones. Investigations along this direction led to the discovery that the easily prepared 2-bromoallyl sulfones 2a,b function as allenyl sulfone surrogates in the presence of cesium carbonate (Scheme
  • b) [24]. Similarly, treatment of 2a with salicylaldehyde furnished the 3-sulfonyl-2H-chromene derivative 4 in 69% yield (Scheme 1, path c) [24]. The formation of allenyl sulfone 5 and propargyl sulfone 6 in the reaction of 2a with cesium carbonate indicated that 5 is an intermediate in the above
  • , stability, and ease of preparation, ortho-hydroxychalcones were considered to be a suitable choice for this purpose. A pilot reaction between the o-hydroxychalcone 7a and bromoallyl sulfone 2a in the presence of 2 equivalents of cesium carbonate in acetonitrile afforded the 4H-chromene derivative 8aa in 61
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Published 06 Jan 2016

Synthesis of Xenia diterpenoids and related metabolites isolated from marine organisms

  • Tatjana Huber,
  • Lara Weisheit and
  • Thomas Magauer

Beilstein J. Org. Chem. 2015, 11, 2521–2539, doi:10.3762/bjoc.11.273

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  • alcohol was converted to the corresponding silyl ether. Next, alkylation of the metalated sulfone with allylic chloride 51 afforded alcohol 52 after desilylation. Subsequent desulfonylation with sodium amalgam and Jones oxidation of the primary alcohol furnished carboxylic acid 53. The corresponding
  • allenic sulfone [44] which, upon conjugate addition of diethyl amine followed by hydrolysis afforded a β-ketosulfone. For the following ring closure, the primary alcohol was desilylated and converted to the corresponding allylic carbonate 71. The cyclononene structure 72 was then assembled via a palladium
  • -catalyzed and base-mediated cyclization of carbonate 71 [45]. Reductive cleavage of the sulfone using aluminium amalgam afforded a ketone, which was converted to an exocyclic double bond by treatment with Tebbe’s reagent [42]. In order to convert the methoxy acetal to the corresponding lactone, without
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Published 10 Dec 2015

Beyond catalyst deactivation: cross-metathesis involving olefins containing N-heteroaromatics

  • Kevin Lafaye,
  • Cyril Bosset,
  • Lionel Nicolas,
  • Amandine Guérinot and
  • Janine Cossy

Beilstein J. Org. Chem. 2015, 11, 2223–2241, doi:10.3762/bjoc.11.241

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  • of 2,6-disubstituted pyridine 60 was treated with GI, the expected macrocycle 61 was obtained (51%) together with the dimeric cyclophane 62 (20%). The authors explained that the sulfone moieties facilitated the RCM by steering the alkenyl chains into a favorable conformation, but it also may be
  • hypothesized that the steric hindrance caused by the sulfone groups might reduce the ability of the nitrogen atom in deactivating the ruthenium catalyst. A desulfonylation followed by a hydrogenation of the double bond afforded normuscopyridine (Scheme 23). Other syntheses of cyclophanes using RCM were
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Published 18 Nov 2015

Recent applications of ring-rearrangement metathesis in organic synthesis

  • Sambasivarao Kotha,
  • Milind Meshram,
  • Priti Khedkar,
  • Shaibal Banerjee and
  • Deepak Deodhar

Beilstein J. Org. Chem. 2015, 11, 1833–1864, doi:10.3762/bjoc.11.199

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  • using catalysts 1 and 2 [32]. The tetraallyl derivative, prepared from 142 by an allylation protocol, was subjected to a RRM sequence in the presence of the catalyst 1 to produce propellane derivative 144 containing an oxa-bowl moiety. In another sequence [33], the alkenylation of sulfone 145 gave the
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Published 07 Oct 2015

Design and synthesis of polycyclic sulfones via Diels–Alder reaction and ring-rearrangement metathesis as key steps

  • Sambasivarao Kotha and
  • Rama Gunta

Beilstein J. Org. Chem. 2015, 11, 1373–1378, doi:10.3762/bjoc.11.148

Graphical Abstract
  • Ramberg–Bäcklund reaction [10] and they can be alkylated via carbanion chemistry. Moreover, they are suitable synthons in Diels–Alder (DA) reactions [11][12][13][14]. In view of various applications of sulfone derivatives, we envisioned a new synthetic strategy based on ring-rearrangement metathesis (RRM
  • polycycles by RRM [27][28] as a key step, here we conceive unique examples where cis and trans ring junctions are produced in the RRM reactions. Results and Discussion Strategy Our retrosynthetic strategy to diverse sulfone derivatives is shown in Figure 1. The target sulfone derivatives 1 could be
  • synthesized from the functionalized tricyclic sulfone 2 by RRM sequence. The sulfone 2 may be prepared from the dimesylate 3, which in turn, can be assembled from the known anhydride 4 via reduction followed by mesylation of the resulting diol. Compound 4 could be prepared via DA reaction starting with
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Published 06 Aug 2015

Selected synthetic strategies to cyclophanes

  • Sambasivarao Kotha,
  • Mukesh E. Shirbhate and
  • Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

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  • ) in quantitative yield. Next, bis-sulfone 239 was reacted with 5-bromo-1-pentene (240) in the presence of NaH to give an inseparable mixture of cis and trans-sulfones 241a and 241b, respectively. An RCM sequence of these sulfones in the presence of the G-I (12) catalyst gave cyclophane 243 (51%) and
  • %). Similar reaction conditions were employed with the dimeric product 242, to generate the macrocyclic pyridinophane 245 (64%). It is interesting to note that when the same strategy was applied with a benzene analogue, dipentenylation of bis-sulfone 246 gave compounds 247 and 248, which were easily separable
  • by column chromatography [174]. Moreover, it was observed that cis-sulfone generates the monomeric cyclophane 249 during the metathesis as confirmed by single crystal X-ray diffraction data while the trans-sulfone gave the dimer 252. Finally, the desulfonylation followed by the hydrogenation sequence
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Published 29 Jul 2015

Regioselective synthesis of chiral dimethyl-bis(ethylenedithio)tetrathiafulvalene sulfones

  • Flavia Pop and
  • Narcis Avarvari

Beilstein J. Org. Chem. 2015, 11, 1105–1111, doi:10.3762/bjoc.11.124

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  • aerial oxidation of the chiral dithiolates generated from the propionitrile-protected precursors. Both enantiomers crystallize in the orthorhombic chiral space group P212121. They show a boat-type conformation of the TTF moiety, a rather rigid dithiin sulfone ring and the methyl groups in a bisequatorial
  • that the oxidation of the outer sulfur atoms into sulfoxide or sulfone should only moderately influence the oxidation potential and thus provide more stable radical cation species. In order to access chiral precursors with controlled stereochemistry we decided to investigate the sulfoxidation of the DM
  • elemental analysis, which are all concordant, the definite proof for the sulfone structure of 1 has been provided by single crystal X-ray diffraction analysis. Single crystals of the two enantiomers (S,S)-1 and (R,R)-1 were obtained by slow evaporation from dichloromethane/pentane or dichloromethane
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Published 02 Jul 2015

Hetero-Diels–Alder reactions of hetaryl and aryl thioketones with acetylenic dienophiles

  • Grzegorz Mlostoń,
  • Paulina Grzelak,
  • Maciej Mikina,
  • Anthony Linden and
  • Heinz Heimgartner

Beilstein J. Org. Chem. 2015, 11, 576–582, doi:10.3762/bjoc.11.63

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  • ESI mass spectra as well as the elemental analysis confirmed the molecular formula C19H16SO6, which corresponds with the structure of the sulfone 6a obtained in 90% yield (Scheme 4). Based on this result, the intermediate product observed in the mixture after 3 h can be proposed as the corresponding
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Published 28 Apr 2015

Synthesis of nanodiamond derivatives carrying amino functions and quantification by a modified Kaiser test

  • Gerald Jarre,
  • Steffen Heyer,
  • Elisabeth Memmel,
  • Thomas Meinhardt and
  • Anke Krueger

Beilstein J. Org. Chem. 2014, 10, 2729–2737, doi:10.3762/bjoc.10.288

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  • nitrogen and sulfur content. All analytical methods yield comparable results around 0.2 mmol g−1. The further reaction depicted in Scheme 1 enables the formation of an aromatic amine at the 2-position of the ring by the oxidation of the thioethers and subsequent substitution of the sulfone by an amino
  • carried out using gaseous ammonia and hence the isolation and purification of the reaction product 11 is very simple. As expected the intensity of the sulfone related IR bands decreases upon amination (but does not vanish as only the SO2Me group in 2-position is exchanged) and new signals corresponding to
  • amino functions (1590 and ~3450 cm−1) appear in the spectrum. Furthermore, the sulfur content of the material is reduced to one half of the original value. This shows that the reaction occurs with high efficiency as the remaining sulfur stems from the conserved sulfone group. From these results it is
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Published 20 Nov 2014

Application of cyclic phosphonamide reagents in the total synthesis of natural products and biologically active molecules

  • Thilo Focken and
  • Stephen Hanessian

Beilstein J. Org. Chem. 2014, 10, 1848–1877, doi:10.3762/bjoc.10.195

Graphical Abstract
  • accomplished through a one-pot Swern oxidation/Wittig olefination protocol followed by hydrogenation to give ketone 127. For further extension of the carbon chain and installation of the trisubstituted double bond, a modified Julia olefination with imidazole sulfone 128 was employed [100][101][102]. Thus
  • , reaction of ketone 127 with the lithium anion of sulfone 128 and treatment of the obtained β-hydroxysulfone with SmI2 led to olefin 129 as a 2:1 mixture of E/Z-isomers. After reduction of the tert-butyl ester to the primary alcohol, the E/Z-isomers could be separated chromatographically. Cleavage of the
  • accessed from (S)-glycidol. The assembly of the two cyclic building blocks and the Roche ester derived middle fragment under formation of the trans-double bonds would utilize phosphonamide and sulfone anion coupling strategy, respectively. A similar strategy was employed for the assembly of ambruticin S
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Published 13 Aug 2014

Olefin cross metathesis based de novo synthesis of a partially protected L-amicetose and a fully protected L-cinerulose derivative

  • Bernd Schmidt and
  • Sylvia Hauke

Beilstein J. Org. Chem. 2014, 10, 1023–1031, doi:10.3762/bjoc.10.102

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  • -benzyloxyhex-5-enal [30], oxidative degradation of aromatics and subsequent lactonization [31], and a two-carbon homologation of an enantiopure C4-building block with a metallated sulfone [32]. A combinatorial biosynthetic approach to D- and L-amicetose has also recently been established by combining different
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Published 06 May 2014

Synthetic scope and DFT analysis of the chiral binap–gold(I) complex-catalyzed 1,3-dipolar cycloaddition of azlactones with alkenes

  • María Martín-Rodríguez,
  • Luis M. Castelló,
  • Carmen Nájera,
  • José M. Sansano,
  • Olatz Larrañaga,
  • Abel de Cózar and
  • Fernando P. Cossío

Beilstein J. Org. Chem. 2013, 9, 2422–2433, doi:10.3762/bjoc.9.280

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  • sulfone, trans-1,2-bis(phenylsulfonyl)ethylene, chalcone, crotonaldehyde and cinnamaldehyde at the same reaction conditions [36]. Another drawback was the poor reactivity observed when α-substituted azlactones were used as starting material in the named reaction with NPM. However, the alanine-derived 4
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Published 11 Nov 2013

Sequential Diels–Alder/[3,3]-sigmatropic rearrangement reactions of β-nitrostyrene with 3-methyl-1,3-pentadiene

  • Peter A. Wade,
  • Alma Pipic,
  • Matthias Zeller and
  • Panagiota Tsetsakos

Beilstein J. Org. Chem. 2013, 9, 2137–2146, doi:10.3762/bjoc.9.251

Graphical Abstract
  • . Nitronic ester 26c with a sulfone group (Hammett σp 0.68) [20] at the C(I) position rearranges at 80 °C to 28b whereas analogous nitronic ester 26d with phenacyl group, a less powerful W-group (Hammett σp 0.43) [20], requires 120 °C for rearrangement to 28c [2]. The [3,3]-sigmatropic rearrangement of 26a
  • similar bicyclic transition state must be involved [2]. The high reactivity of nitronic ester 30 is presumably due to the combined presence of a C(I) sulfone group and a C(IV) methyl group. In particular, the presence of an electron-attracting substituent at C(I) appears to have a greater accelerative
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Published 17 Oct 2013

The chemistry of isoindole natural products

  • Klaus Speck and
  • Thomas Magauer

Beilstein J. Org. Chem. 2013, 9, 2048–2078, doi:10.3762/bjoc.9.243

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  • (52) and cytochalasin L-696,474 (78) diverged. For 78, another five steps were necessary to form the isoindolinone 74. After oxidation of the primary alcohol with Dess–Martin periodinane, the obtained aldehyde was coupled with the readily available N-phenyltetrazole sulfone 75 via a Julia–Kocienski
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Published 10 Oct 2013

Stereoselective synthesis of the C79–C97 fragment of symbiodinolide

  • Hiroyoshi Takamura,
  • Takayuki Fujiwara,
  • Isao Kadota and
  • Daisuke Uemura

Beilstein J. Org. Chem. 2013, 9, 1931–1935, doi:10.3762/bjoc.9.228

Graphical Abstract
  • Julia–Kocienski olefination as the coupling reaction. The new retrosynthetic analysis of the C79–C97 fragment 8 is described in Scheme 2. We envisaged that the diol 8 could be synthesized by the Julia–Kocienski olefination [12][13][14] between aldehyde 9 and 1-phenyl-1H-tetrazol-5-yl (PT)-sulfone 10 and
  • /Mo(VI) [23] to yield PT-sulfone 23. The TBDPS protecting group of 23 was transformed to the TBS group in two steps to provide PT-sulfone 24. With the coupling precursors aldehyde 20 and PT-sulfones 23 and 24 in hand, we next examined the Julia–Kocienski olefination [12][13][14] of these compounds
  • (Table 1). Deprotonation of the PT-sulfone 23 with KHMDS, followed by addition of the aldehyde 20, gave rise to the desired coupling product (E)-25 along with (Z)-25 in 27% combined yield at a 3.5:1 diastereomeric ratio (Table 1, entry 1). When NaHMDS was used as the base, the chemical yield was improved
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Published 25 Sep 2013

Ethyl diazoacetate synthesis in flow

  • Mariëlle M. E. Delville,
  • Jan C. M. van Hest and
  • Floris P. J. T. Rutjes

Beilstein J. Org. Chem. 2013, 9, 1813–1818, doi:10.3762/bjoc.9.211

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  • elimination of the sulfone substituent. Additionally, Ley et al. [19] recently prepared a range of α-hydroxy acids in flow starting from the corresponding amino acids, involving diazotization of the amine to the diazonium salt in a biphasic system. Inspired by Ley’s approach, which is significantly more atom
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Published 05 Sep 2013

Dipolar addition to cyclic vinyl sulfones leading to dual conformation tricycles

  • Steven S. Y. Wong,
  • Michael G. Brant,
  • Christopher Barr,
  • Allen G. Oliver and
  • Jeremy E. Wulff

Beilstein J. Org. Chem. 2013, 9, 1419–1425, doi:10.3762/bjoc.9.159

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  • coupling partners for these cycloadditions, and in many cases the reaction rate can be enhanced through the addition of a Lewis acid that can coordinate to the carbonyl function, thereby lowering the energy of the olefin LUMO. By contrast, vinyl sulfones (with the exception of simple aryl vinyl sulfone
  • species [13][14][15][16][17][18][19][20][21]) have been less-frequently employed as acceptors in 1,3-dipolar cycloadditions [22][23][24][25]. Indeed, we are only aware of a single prior example of a cyclic alkyl vinyl sulfone participating in a dipolar addition with an azomethine ylide [26]. In part, this
  • lack of reactivity is due to a poor orbital overlap between the sulfone and olefin functions [27][28][29]; while vinyl sulfones are electrophilic (due to the inductive effects of the sulfone group), their LUMO cannot be as easily perturbed by the addition of a Lewis acid. We previously described the
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Published 15 Jul 2013

Homolytic substitution at phosphorus for C–P bond formation in organic synthesis

  • Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 1269–1277, doi:10.3762/bjoc.9.143

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  • the regioselectivity, these addition reactions naturally involve C–P bond formation by homolytic substitution at phosphorus (Scheme 5). Studer recently reported similar silylphosphination of phenyl vinyl sulfone with Me3Si–PPh2 [26]. Tzschach reported that tetraorganodiphosphines R2P–PR2 add to
  • Me3M–PPh2 (M = Sn, Si) and V-40 (Table 9) [26]. Secondary and tertiary alkyl iodides participate in the addition reaction while primary alkyl iodide results in direct phosphination prior to the expected addition. Not only acrylate ester but also acrylamide, vinyl sulfone, and acrylonitrile are good
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Published 28 Jun 2013

Appel-reagent-mediated transformation of glycosyl hemiacetal derivatives into thioglycosides and glycosyl thiols

  • Tamashree Ghosh,
  • Abhishek Santra and
  • Anup Kumar Misra

Beilstein J. Org. Chem. 2013, 9, 974–982, doi:10.3762/bjoc.9.112

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  • ][2][3][4][5]. Due to their thermal and chemical stability, they have been used as stable intermediates for functional-group transformations as well as stereoselective glycosylations. Thioglycosides can be transformed into various other glycosyl donors [6][7][8][9][10] (e.g., sulfoxide, sulfone
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Published 22 May 2013

Some aspects of radical chemistry in the assembly of complex molecular architectures

  • Béatrice Quiclet-Sire and
  • Samir Z. Zard

Beilstein J. Org. Chem. 2013, 9, 557–576, doi:10.3762/bjoc.9.61

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  • addition to phenyl vinyl sulfone and closure to form the cyclopentane ring in 19, and then by a second intermolecular addition to phenyl vinyl sulfone to furnish radical 20, which finally evolves into the observed product 21 by transfer of the pyridylthiyl group from the starting Barton ester 16. Even
  • carboxylic acid derivative 23 [18]. As in the previous sequence, radical 24, generated following the second addition to the vinyl sulfone, is electrophilic in character and does not add further; it simply propagates the chain by reacting with the starting thiohydroxamate 23. The complex bicyclic structure 25
  • , exposure of bis-sulfone 25 to trimethylaluminium causes the regioselective replacement of the terminal sulfone with a methyl group to give compound 26 in good yield. The Barton decarboxylation reaction is an exceptionally powerful method that deserves without doubt a much greater attention from synthetic
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Published 18 Mar 2013

Recent advances in transition-metal-catalyzed intermolecular carbomagnesiation and carbozincation

  • Kei Murakami and
  • Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 278–302, doi:10.3762/bjoc.9.34

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  • -substituted alkynes, such as alkynyl sulfones, sulfoxides, or sulfoximines as electron-deficient alkynes. Xie reported a copper-catalyzed carbomagnesiation of alkynyl sulfone to give the corresponding alkenylmagnesium intermediates (Scheme 2) [39][40]. Interestingly, the stereochemistry of the products was
  • allylmagnesiation of alkynyl sulfone. Copper-catalyzed four-component reaction of alkynyl sulfoxide with alkylzinc reagent, diiodomethane, and benzaldehyde. Rhodium-catalyzed reaction of aryl alkynyl ketones with arylzinc reagents. Allylmagnesiation of propargyl alcohol, which provides the anti-addition product
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Published 11 Feb 2013

The chemistry of bisallenes

  • Henning Hopf and
  • Georgios Markopoulos

Beilstein J. Org. Chem. 2012, 8, 1936–1998, doi:10.3762/bjoc.8.225

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Published 15 Nov 2012

Organocatalytic cascade aza-Michael/hemiacetal reaction between disubstituted hydrazines and α,β-unsaturated aldehydes: Highly diastereo- and enantioselective synthesis of pyrazolidine derivatives

  • Zhi-Cong Geng,
  • Jian Chen,
  • Ning Li,
  • Xiao-Fei Huang,
  • Yong Zhang,
  • Ya-Wen Zhang and
  • Xing-Wang Wang

Beilstein J. Org. Chem. 2012, 8, 1710–1720, doi:10.3762/bjoc.8.195

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  • screening results are summarized in Table 3. (S)-Proline derivatives 1g–h, 1k, 1l were found to be ineffective for the reaction, because they afford only trace products after one day (Table 3, entries 1, 2, 5 and 6). Although a moderate yield was obtained with organocatalyst 1i bearing a sulfone functional
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Published 09 Oct 2012

Synthesis of compounds related to the anti-migraine drug eletriptan hydrobromide

  • Suri Babu Madasu,
  • Nagaji Ambabhai Vekariya,
  • M. N. V. D. Hari Kiran,
  • Badarinadh Gupta,
  • Aminul Islam,
  • Paul S. Douglas and
  • Korupolu Raghu Babu

Beilstein J. Org. Chem. 2012, 8, 1400–1405, doi:10.3762/bjoc.8.162

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  • -3-(N-methylpyrrolidin-2-ylmethyl)-1H-indole (9) by using acetic anhydride and triethylamine in N,N-dimethylformamide affords (R)-1-acetyl-5-bromo-3-(N-methylpyrrolidin-2-ylmethyl)-1H-indole (10). When coupled in situ with phenyl vinyl sulfone (11) in the presence of a catalytic amount of palladium
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Published 30 Aug 2012
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