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Search for "potassium thioacetate" in Full Text gives 13 result(s) in Beilstein Journal of Organic Chemistry.
Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments
- Aissam Okba,
- Pablo Simón Marqués,
- Kyohei Matsuo,
- Naoki Aratani,
- Hiroko Yamada,
- Gwénaël Rapenne and
- Claire Kammerer
Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30
- derivative 21 was synthesized in six steps in 14% overall yield from 3-bromothiophene (17, Scheme 7). In the first step, the sulfur atom embedded in the final thiepine ring was introduced via a palladium-catalyzed S-arylation of 3-bromothiophene in the presence of potassium thioacetate, to afford the
Graphical Abstract
Scheme 1: “Precursor approach” for the synthesis of π-conjugated polycyclic compounds, with the thermally- or...
Scheme 2: Valence isomerization of chalcogen heteropines and subsequent cheletropic extrusion in the case of ...
Scheme 3: Early example of phenanthrene synthesis via a chemically-induced S-extrusion (and concomitant decar...
Scheme 4: Top: Conversion of dinaphthothiepine bisimides 3a,b and their sulfoxide analogues 4a,b into PBIs 6a,...
Figure 1: Top view (a) and side view (b) of the X-ray crystal structure of thiepine 3b showing its bent confo...
Scheme 5: Modular synthetic route towards dinaphthothiepines 3a–f and the corresponding S-oxides 4a–d, incorp...
Scheme 6: Top: Conversion of dithienobenzothiepine monomeric units into dithienonaphthalenes, upon S-extrusio...
Scheme 7: Synthesis of S-doped extended triphenylene derivative 22 from 3-bromothiophene (17) with the therma...
Scheme 8: Top: Synthesis of thermally-stable O-doped HBC 26a. Bottom: Synthesis of S- and Se-based soluble pr...
Scheme 9: Synthesis of dinaphthooxepine bisimide 33 and conversion into PBI 6f by O-extrusion triggered by el...
Figure 2: Cyclic voltammogram of dinaphthooxepine 33, evidencing the irreversibility of the reduction process...
Scheme 10: Top: Early example of 6-membered ring contraction with concomitant S-extrusion leading to dinaphtho...
Scheme 11: Examples of S-extrusion from annelated 1,2-dithiins under photoactivation (top) or thermal activati...
Scheme 12: Synthesis of dibenzo[1,4]dithiapentalene upon photoextrusion of SO2 [78].
Scheme 13: Extrusion of SO in naphthotrithiin-2-oxides for the synthesis of 2,5-dihydrothiophene 1-oxides [79].
Scheme 14: SO-extrusion as a key step in the synthesis of fullerenes (C60 and C70) encapsulating H2 molecules [80,82]....
Scheme 15: Synthesis of diepoxytetracene precursor 56 and its on-surface conversion into tetracene upon O-extr...
Scheme 16: Soluble precursors of hexacene, decacene and dodecacene incorporating 1,4-epoxides in their hydroca...
Scheme 17: Synthesis of tetraepoxide 59 as soluble precursor of decacene [85].
Figure 3: Constant-height STM measurement of decacene on Au(111) using a CO-functionalized tip (sample voltag...
Synthesis of ether lipids: natural compounds and analogues
- Marco Antônio G. B. Gomes,
- Alicia Bauduin,
- Chloé Le Roux,
- Romain Fouinneteau,
- Wilfried Berthe,
- Mathieu Berchel,
- Hélène Couthon and
- Paul-Alain Jaffrès
Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96
- presence of dimethylaminopyridine (DMAP). Then, 27.2 reacted with potassium thioacetate to produce the thioester 27.3. Its reduction with lithium aluminium hydride produced the free thiol 27.4 that was used as nucleophile on octadecyl iodide to install the C18 lipid chain. The deprotection of the primary
Graphical Abstract
Figure 1: Chemical structure of some natural ether lipids (ELs).
Figure 2: Synthesis of lyso-PAF and PAF from 1-O-alkylglycerol [64].
Figure 3: Synthesis of lyso-PAF from 1,3-benzylideneglycerol 3.1 [69].
Figure 4: A) Synthesis of the two enantiomers of octadecylglycerol (4.6 and 4.10) from ᴅ-mannitol (4.1); B) s...
Figure 5: Four-step synthesis of PAF 5.6 from (S)-glycidol [73].
Figure 6: Synthesis of 1-O-alkylglycerol A) from solketal, B) from ᴅ- or ʟ-tartaric acid and the intermediate ...
Figure 7: Synthesis of EL building blocks starting from substituted glycidol 7.1a–c [82].
Figure 8: Synthesis of PAF 8.5 by using phosphoramidite 8.2 [86].
Figure 9: Synthesis of oleyl-PAF 9.7 from ʟ-serine [88].
Figure 10: Synthesis of racemic analogues of lyso-PAF 10.8 and PAF 10.9 featuring a phenyl group between the g...
Figure 11: Synthesis of racemic deoxy-lyso-PAF 11.7 and deoxy-PAF 11.8 [91].
Figure 12: Synthesis of racemic thio-PAF 12.8 [93].
Figure 13: Racemic synthesis of 13.6 to illustrate the modification of the glycerol backbone by adding a methy...
Figure 14: Racemic synthesis of 14.5 as an illustration of the introduction of methyl substituents on the glyc...
Figure 15: Synthesis of functionalized sn-2-acyl chains of PC-EL; A) Steglich esterification or acylation reac...
Figure 16: Synthesis of racemic mc-PAF (16.3), a carbamate analogue of PAF [102].
Figure 17: A) Synthesis of (R)-17.2 and (S)-17.6 starting from (S)-solketal (17.1); B) synthesis of N3-PAF (17...
Figure 18: Modification of the phosphocholine polar head to produce PAF analogues [81].
Figure 19: Racemic PAF analogues 19.3 and 19.5 characterized by the absence of the phosphate group [107].
Figure 20: Synthesis of PIP3-PAF (20.7) [108].
Figure 21: Large-scale synthesis of C18-edelfosine (21.8) [116].
Figure 22: Synthesis of C16-edelfosine (22.10) starting from isopropylidene-ʟ-glyceric acid methyl ester (22.1...
Figure 23: Phosphocholine moiety installation by the use of chlorophosphite 23.2 as key reagent [119].
Figure 24: Synthesis of rac-1-alkyl-2-O-methylglycerol (AMG) [120].
Figure 25: Synthesis of stereocontrolled 1-alkyl-2-O-methyl glycerol 25.9 (AMG) from dimethyl ᴅ-tartrate [81].
Figure 26: A) Racemic synthesis of thioether 26.4 [129,130], B) structure of sulfone analogue 26.5 [129].
Figure 27: Stereocontrolled synthesis of C18-edelfosine thioether analogue 27.8 [118].
Figure 28: Synthesis of thioether 28.4 that include a thiophosphate function [134].
Figure 29: Synthesis of ammonium thioether 29.4 and 29.6 [135].
Figure 30: Synthesis of the N-methylamino analogue of edelfosine 30.6 (BN52211) [138].
Figure 31: Synthesis of 1-desoxy analogues of edelfosine; A) with a saturated alkyl chain; B) synthesis of the...
Figure 32: Stereocontrolled synthesis of edelfosine analogue (S)-32.8 featuring a C18:1 lipid chain [142].
Figure 33: Synthesis of edelfosine analogues with modulation of the lipid chain; A) illustration with the synt...
Figure 34: Synthesis of phospholipid featuring a carbamate function to link the lipid chain to the glycerol un...
Figure 35: Synthesis of sesquiterpene conjugates of phospho glycero ether lipids [148].
Figure 36: Racemic synthesis of methyl-substituted glycerol analogues 36.7 and 36.10: A) synthesis of diether ...
Figure 37: Racemic synthesis of ilmofosine (37.6) [155,156].
Figure 38: A) Stereoselective synthesis of 38.5 via a stereoselective hydroboration reaction; B) synthesis of ...
Figure 39: Racemic synthesis of SRI62-834 (39.6) featuring a spiro-tetrahydrofurane heterocycle in position 2 ...
Figure 40: Racemic synthesis of edelfosine analogue 40.5 featuring an imidazole moiety in sn-2 position [160].
Figure 41: Racemic synthesis of fluorine-functionalized EL: A) Synthesis of 41.6 and B) synthesis of 41.8 [161-163].
Figure 42: A) Synthesis of the β-keto-ester 42.6 that also features a decyl linker between the phosphate and t...
Figure 43: Synthesis of phosphonate-based ether lipids; A) edelfosine phosphonate analogue 43.7 and B) thioeth...
Figure 44: Enantioselective synthesis of phosphonates 44.3 and 44.4 [171].
Figure 45: Racemic synthesis of phosphinate-based ether lipid 45.10 [172].
Figure 46: Racemic synthesis of edelfosine arsonium analogue 46.5 [173].
Figure 47: Synthesis of edelfosine dimethylammonium analogue 47.2 [118].
Figure 48: Synthesis of rac-C18-edelfosine methylammonium analogue 48.4 [176].
Figure 49: A) Synthesis of edelfosine N-methylpyrrolidinium analogue 49.2 or N-methylmorpholinium analogue 49.3...
Figure 50: A) Synthesis of edelfosine’s analogue 50.4 with a PE polar group; B) illustration of a pyridinium d...
Figure 51: A) Synthesis of 51.4 featuring a thiazolium cationic moiety; B) synthesis of thiazolium-based EL 51...
Figure 52: Synthesis of cationic ether lipids 52.3, 52.4 and 52.6 [135,183].
Figure 53: Synthesis of cationic carbamate ether lipid 53.5 [184].
Figure 54: Synthesis of cationic sulfonamide 54.5 [185].
Figure 55: Chemical structure of ONO-6240 (55.1) and SRI-63-119 (55.2).
Figure 56: Synthesis of non-ionic ether lipids 56.2–56.9 [188].
Figure 57: Synthesis of ether lipid conjugated to foscarnet 57.6 [189].
Figure 58: A) Synthesis of ether lipid conjugated to arabinofuranosylcytosine; B) synthesis of AZT conjugated ...
Figure 59: Synthesis of quercetin conjugate to edelfosine [191].
Figure 60: Synthesis of 60.8 (Glc-PAF) [194].
Figure 61: A) Synthesis of amino ether lipid 61.7 functionalized with a rhamnose unit and its amide analogue 6...
Figure 62: A) Synthesis of glucose ether lipid 62.4; B) structure of ether lipid 62.5 possessing a maltose uni...
Figure 63: A) Synthesis of glucuronic methyl ester 63.8; B) structure of cellobiose 63.9 and maltose 63.10 ana...
Figure 64: A) Synthesis of maltosyl glycerolipid 64.7; B) structure of lactose analogue 64.8 prepared followin...
Figure 65: A) Asymmetric synthesis of the aglycone moiety starting from allyl 4-methoxyphenyl ether; B) glycos...
Figure 66: A) Synthesis of ohmline possessing a lactose moiety. B) Structure of other glyco glycero lipids pre...
Figure 67: A) Synthesis of lactose-glycerol ether lipid 67.5; B) analogues possessing a maltose (67.6) or meli...
Figure 68: Synthesis of digalactosyl EL 68.6, A) by using trityl, benzyl and acetyl protecting groups, B) by u...
Figure 69: A) Synthesis of α-ohmline; B) structure of disaccharide ether lipids prepared by using similar meth...
Figure 70: Synthesis of lactose ether lipid 70.3 and its analogue 70.6 featuring a carbamate function as linke...
Figure 71: Synthesis of rhamnopyranoside diether 71.4 [196].
Figure 72: Synthesis of 1-O-hexadecyl-2-O-methyl-3-S-(α-ᴅ-1'-thioglucopyranosyl)-sn-glycerol (72.5) [225].
Figure 73: A) Preparation of lipid intermediate 73.4; B) synthesis of 2-desoxy-C-glycoside 73.10 [226].
Figure 74: Synthesis of galactose-pyridinium salt 74.3 [228].
Figure 75: Synthesis of myo-inositol derivative Ino-C2-PAF (75.10) [230].
Figure 76: A) Synthesis of myo-inositol phosphate building block 76.7; B) synthesis of myo-inositolphosphate d...
Figure 77: A) Synthesis of phosphatidyl-3-desoxy-inositol 77.4; B) synthesis of phosphono-3-desoxyinositol 77.9...
Figure 78: A) Structure of diether phosphatidyl-myo-inositol-3,4-diphosphate 78.1; B) synthesis of phosphatidy...
Figure 79: A) Synthesis of diether-phosphatidyl derivative 79.4 featuring a hydroxymethyl group in place of a ...
Figure 80: Synthesis of Glc-amine-PAF [78].
Figure 81: Synthesis of glucosamine ether lipid 81.4 and its analogues functionalized in position 3 of the ami...
Figure 82: Synthesis of fully deprotected aminoglucoside ether lipid 82.5 [246].
Figure 83: Synthesis of C-aminoglycoside 83.12 using Ramberg–Bäcklund rearrangement as a key step [250].
Figure 84: A) List of the most important glyco lipids and amino glyco lipids included in the study of Arthur a...
Figure 85: Synthesis of mannosamine ether lipid 85.6 [254].
Figure 86: A) Synthesis of glucosamine ether lipids with a non-natural ʟ-glucosamine moiety; B) synthesis of e...
Figure 87: A) Structure of the most efficient anticancer agents 87.1–87.4 featuring a diamino glyco ether lipi...
Figure 88: A) Synthesis of diamino glyco ether lipid 87.4; B) synthesis of bis-glycosylated ether lipid 88.10 [256]....
Figure 89: Synthesis of triamino ether lipid 89.4 [260].
Figure 90: Synthesis of chlorambucil conjugate 90.7 [261].
Figure 91: Three main methods for the preparation of glycerol ether lipid 91.3; A) from solketal and via a tri...
Figure 92: Four different methods for the installation of the phosphocholine polar head group; A) method using...
Figure 93: Illustration of two methods for the installation of saccharides or aminosaccharides; A) O-glycosyla...
Selenophene-containing heterotriacenes by a C–Se coupling/cyclization reaction
- Pierre-Olivier Schwartz,
- Sebastian Förtsch,
- Astrid Vogt,
- Elena Mena-Osteritz and
- Peter Bäuerle
Beilstein J. Org. Chem. 2019, 15, 1379–1393, doi:10.3762/bjoc.15.138
- ), tetrabutylammonium fluoride, selenourea, and copper oxide nanoparticles were purchased from Sigma-Aldrich. n-Butyllithium in n-hexane (1.6 M) was purchased from Acros Organics, selenophene from TCI, 3-bromothiophene from Fluorochem, potassium thioacetate from Alfa Aesar, potassium sulfide from Caesar & Loretz, and
Graphical Abstract
Figure 1: Heterotriacenes DTT 1, DTS 2, DST 3, and DSS 4 with varying number of selenium atoms and fused sele...
Scheme 1: Synthesis of heterotriacenes DTT 1 and DTS 2 via copper-catalyzed cross-coupling reactions.
Scheme 2: Synthesis of selenolotriacenes DST 3 and DSS 4.
Figure 2: Single crystal X-ray structure analysis of selenolotriacene DST 3, (a) individual molecule and atom...
Figure 3: Single crystal X-ray structure analysis of selenolotriacene DST 3: (a) partial overlap of stacked a...
Figure 4: DFT quantum chemical calculated geometry of DTT 1 and general atom labelling for all heterotriacene...
Figure 5: Representative electron density of frontier orbitals LUMO, HOMO, and HOMO-1 for heterotriacene DSS 4...
Figure 6: Normalized absorption spectra of heteroacenes DTT 1 (black line), DTS 2 (blue line), DST 3 (green l...
Figure 7: Energy diagram of the frontier molecular orbitals of heterotriacenes 1–4.
Figure 8: Multisweep voltammograms for the electrochemical polymerization of monomeric heterotriacene DST 2 i...
Scheme 3: Oxidative polymerization of heterotriacenes 1–4 to corresponding conjugated polymers P1–P4.
Thiol-free chemoenzymatic synthesis of β-ketosulfides
- Adrián A. Heredia,
- Martín G. López-Vidal,
- Marcela Kurina-Sanz,
- Fabricio R. Bisogno and
- Alicia B. Peñéñory
Beilstein J. Org. Chem. 2019, 15, 378–387, doi:10.3762/bjoc.15.34
- Scheme 3, α-chloroacetophenone (1.0 g, 6.47 mmol) was reacted with 1.1 equiv of potassium thioacetate, 1.1 equiv of allyl bromide and 2 equiv of K2CO3 in 5 mL of DMSO. After 24 h, 45 mL of buffer (Tris·HCl 50 mM pH 7.5) were added. Then, KH2PO4 was added in order to reach pH ≈7.5, followed by 200 mg of
- chemoenzymatic synthesis of β-ketosulfides. One-pot two-step preparation of phenacylalkylsulfides. aReaction conditions: i. α-haloketone (0.25 mmol), potassium thioacetate (1.1 equiv), alkyl halide (1.1 equiv) and K2CO3 (2.0 equiv) in 500 µL of DMSO, 5 h at room temperature; ii. 100 mg of CAL-B (Novozyme 435
- ) and 9.5 mL of Tris·HCl buffer (50 mM pH 7.5), 30 °C, 24 h, 250 rpm. bReaction performed using 1.0 g of α-chloroacetophenone, potassium thioacetate (1.1 equiv), alkyl halide (1.1 equiv) and K2CO3 (2.0 equiv) in 5 mL of DMSO, 200 mg of CAL-B and 45 mL of Tris-HCl buffer (50 mM pH 7.5), 24 h at room
Graphical Abstract
Figure 1: Selected examples of valuable β-ketosulfides. A: bioactive synthetic compounds, B: natural products....
Scheme 1: Different strategies for the preparation of β-ketosulfides.
Scheme 2: Thiol-free chemoenzymatic synthesis of β-ketosulfides.
Figure 2: Time-course plot for the CAL-B catalysed hydrolysis of 1a.
Scheme 3: One-pot two-step preparation of phenacylalkylsulfides. aReaction conditions: i. α-haloketone (0.25 ...
Scheme 4: Selective oxidation of the β-ketosulfide 2a.
Hypervalent organoiodine compounds: from reagents to valuable building blocks in synthesis
- Gwendal Grelier,
- Benjamin Darses and
- Philippe Dauban
Beilstein J. Org. Chem. 2018, 14, 1508–1528, doi:10.3762/bjoc.14.128
- 66 following the reaction of cyclic diaryl-λ3-iodanes with potassium thioacetate as the sulfur donor, and CuCl2 as the catalyst (Scheme 29) [69]. The reaction can be performed either in THF or DMSO, affording both symmetrical and non-symmetrical products in good to excellent yields. The scope of the
- corresponding cyclic diaryl-λ3-iodanes, utilizing potassium thioacetate as the sulfur source, in the presence of 10 mol % of Cu(OTf)2, and 12 mol % of 1,10-phenanthroline [70]. This transformation has been successfully applied to linear diaryl-λ3-iodanes (Scheme 39). Interestingly, symmetrical and non
Graphical Abstract
Scheme 1: Strategies to address the issue of sustainability with polyvalent organoiodine reagents.
Scheme 2: Functionalization of ketones and alkenes with IBX.
Scheme 3: Functionalization of pyrroles with DMP.
Scheme 4: Catalytic benzoyloxy-trifluoromethylation reported by Szabó.
Scheme 5: Catalytic benzoyloxy-trifluoromethylation reported by Mideoka.
Scheme 6: Catalytic 1,4-benzoyloxy-trifluoromethylation of dienes.
Scheme 7: Catalytic benzoyloxy-trifluoromethylation of allylamines.
Scheme 8: Catalytic benzoyloxy-trifluoromethylation of enynes.
Scheme 9: Catalytic benzoyloxy-trifluoromethylation of allenes.
Scheme 10: Alkynylation of N-(aryl)imines with EBX for the formation of furans.
Scheme 11: Catalytic benzoyloxy-alkynylation of diazo compounds.
Scheme 12: Catalytic asymmetric benzoyloxy-alkynylation of diazo compounds.
Scheme 13: Catalytic 1,2-benzoyloxy-azidation of alkenes.
Scheme 14: Catalytic 1,2-benzoyloxy-azidation of enamides.
Scheme 15: Catalytic 1,2-benzoyloxy-iodination of alkenes.
Scheme 16: Seminal study with cyclic diaryl-λ3-iodane.
Scheme 17: Synthesis of alkylidenefluorenes from cyclic diaryl-λ3-iodanes.
Scheme 18: Synthesis of alkyne-substituted alkylidenefluorenes.
Scheme 19: Synthesis of phenanthrenes from cyclic diaryl-λ3-iodanes.
Scheme 20: Synthesis of dibenzocarbazoles from cyclic diaryl-λ3-iodanes.
Scheme 21: Synthesis of triazolophenantridines from cyclic diaryl-λ3-iodanes.
Scheme 22: Synthesis of functionalized benzoxazoles from cyclic diaryl-λ3-iodanes.
Scheme 23: Sequential difunctionalization of cyclic diaryl-λ3-iodanes.
Scheme 24: Double Suzuki–Miyaura coupling reaction of cyclic diaryl-λ3-iodanes.
Scheme 25: Synthesis of a δ-carboline from cyclic diaryl-λ3-iodane.
Scheme 26: Synthesis of N-(aryl)carbazoles from cyclic diaryl-λ3-iodanes.
Scheme 27: Synthesis of carbazoles from cyclic diaryl-λ3-iodanes.
Scheme 28: Synthesis of carbazoles and acridines from cyclic diaryl-λ3-iodanes.
Scheme 29: Synthesis of dibenzothiophenes from cyclic diaryl-λ3-iodanes.
Scheme 30: Synthesis of various sulfur heterocycles from cyclic diaryl-λ3-iodanes.
Scheme 31: Synthesis of dibenzothioheterocycles from cyclic diaryl-λ3-iodanes.
Scheme 32: Synthesis of dibenzosulfides and dibenzoselenides from cyclic diaryl-λ3-iodanes.
Scheme 33: Synthesis of dibenzosulfones from cyclic diaryl-λ3-iodanes.
Scheme 34: Seminal study with linear diaryl-λ3-iodanes.
Scheme 35: N-Arylation of benzotriazole with symmetrical diaryl-λ3-iodanes.
Scheme 36: Tandem catalytic C–H/N–H arylation of indoles with diaryl-λ3-iodanes.
Scheme 37: Tandem N-arylation/C(sp2)–H arylation with diaryl-λ3-iodanes.
Scheme 38: Catalytic intermolecular diarylation of anilines with diaryl-λ3-iodanes.
Scheme 39: Catalytic synthesis of diarylsulfides with diaryl-λ3-iodanes.
Scheme 40: α-Arylation of enolates using [bis(trifluoroacetoxy)iodo]arenes.
Scheme 41: Mechanism of the α-arylation using [bis(trifluoroacetoxy)iodo]arene.
Scheme 42: Catalytic nitrene additions mediated by [bis(acyloxy)iodo]arenes.
Scheme 43: Tandem of C(sp3)–H amination/sila-Sonogashira–Hagihara coupling.
Scheme 44: Tandem reaction using a λ3-iodane as an oxidant, a substrate and a coupling partner.
Scheme 45: Synthesis of 1,2-diarylated acrylamidines with ArI(OAc)2.
Atom-economical group-transfer reactions with hypervalent iodine compounds
- Andreas Boelke,
- Peter Finkbeiner and
- Boris J. Nachtsheim
Beilstein J. Org. Chem. 2018, 14, 1263–1280, doi:10.3762/bjoc.14.108
- counterparts 1 (Scheme 4) [26][27]. Jiang and co-workers developed a Cu(II)-catalysed methodology for the conversion of acyclic diaryliodonium salts 1 and potassium thioacetate to the corresponding thioethers 5 (pathway (a)) and later applied the optimized reaction conditions towards cyclic iodonium salts. In
Graphical Abstract
Scheme 1: Overview of different types of iodane-based group-transfer reactions and their atom economy based o...
Scheme 2: (a) Structure of diaryliodonium salts 1. (b) Diarylation of a suitable substrate A with one equival...
Scheme 3: Synthesis of biphenyls 3 and 3’ with symmetrical diaryliodonium salts 1.
Scheme 4: Synthesis of diaryl thioethers 5.
Scheme 5: Synthesis of two distinct S-aryl dithiocarbamates 7 and 7’ from one equivalent of diaryliodonium sa...
Scheme 6: Synthesis of substituted isoindolin-1-ones 9 from 2-formylbenzonitrile 8 and the postulated reactio...
Scheme 7: Domino C-/N-arylation of indoles 10.
Scheme 8: Domino modification of N-heterocycles 12 via in situ-generated directing groups.
Scheme 9: Synthesis of triarylamines 17 through a double arylation of anilines.
Scheme 10: Selective conversion of novel aryl(imidazolyl)iodonium salts 1b to 1,5-disubstituted imidazoles 18.
Scheme 11: Selected examples for the application of cyclic diaryliodonium salts 19.
Scheme 12: Tandem oxidation–arylation sequence with (dicarboxyiodo)benzenes 20.
Scheme 13: Oxidative α-arylation via the transfer of an intact 2-iodoaryl group.
Scheme 14: Tandem ortho-iodination/O-arylation cascade with PIDA derivatives 20b.
Scheme 15: Synthesis of meta-N,N-diarylaminophenols 28 and the postulated mechanism.
Scheme 16: (Dicarboxyiodo)benzene-mediated metal-catalysed C–H amination and arylation.
Scheme 17: Postulated mechanism for the amination–arylation sequence.
Scheme 18: Auto-amination and cross-coupling of PIDA derivatives 20c.
Scheme 19: Tandem C(sp3)–H olefination/C(sp2)–H arylation.
Scheme 20: Atom efficient functionalisations with benziodoxolones 36.
Scheme 21: Atom-efficient synthesis of furans 39 from benziodoxolones 36a and their further derivatisations.
Scheme 22: Oxyalkynylation of diazo compounds 42.
Scheme 23: Enantioselective oxyalkynylation of diazo compounds 42’.
Scheme 24: Iron-catalysed oxyazidation of enamides 45.
1H-Imidazol-4(5H)-ones and thiazol-4(5H)-ones as emerging pronucleophiles in asymmetric catalysis
- Antonia Mielgo and
- Claudio Palomo
Beilstein J. Org. Chem. 2016, 12, 918–936, doi:10.3762/bjoc.12.90
- solids in good yields. The starting α-mercaptocarboxylic acids can be prepared by reaction of the corresponding α-bromo derivatives with potassium thioacetate followed by treatment with ammonia in methanol [84]. 2.2 Thiazol-4(5H)-ones 2 as pronucleophiles in asymmetric catalytic reactions The potential
Graphical Abstract
Figure 1: Some α-substituted heterocycles for asymmetric catalysis, their reactivity patterns against enoliza...
Figure 2: 1H-Imidazol-4(5H)-ones 1 and thiazol-4(5H)-ones 2.
Scheme 1: a) Synthesis of 2-thio-1H-imidazol-4(5H)-ones [55] and b) preparation of the starting thiohydantoins [59].
Scheme 2: Selected examples of the Michael addition of 2-thio-1H-imidazol-4(5H)-ones to nitroalkenes [55]. aReact...
Scheme 3: Michael addition of thiohydantoins to nitrostyrene assisted by Et3N and catalysts C1 and C3. aAbsol...
Scheme 4: Elaboration of the Michael adducts coming from the Michael addition to nitroalkenes [55].
Figure 3: Proposed model for the Michael addition of 1H-imidazol4-(5H)-ones and selected 1H NMR data which su...
Scheme 5: Michael addition 2-thio-1H-imidazol-4(5H)-ones to the α-silyloxyenone 29 [55].
Scheme 6: Elaboration of the Michael adducts coming from the Michael addition to nitroolefins [55].
Scheme 7: Rhodanines in asymmetric catalytic reactions: a) Reaction with rhodanines of type 44 [78-80]; b) reactions...
Scheme 8: Michael addition of thiazol-4(5H)-ones to nitroolefins promoted by the ureidopeptide-like bifunctio...
Figure 4: Ureidopeptide-like Brønsted bases: catalyst design. a) Previous known design. b) Proposed new desig...
Scheme 9: Ureidopeptide-like Brønsted base bifunctional catalyst preparation. NMM = N-methylmorpholine, THF =...
Scheme 10: Selected examples of the Michael addition of thiazolones to different nitroolefins promoted by cata...
Scheme 11: Elaboration of the Michael adducts to α,α-disubstituted α-mercaptocarboxylic acid derivatives [85].
Scheme 12: Effect of the nitrogen atom at the aromatic substituent of the thiazolone on yield and stereoselect...
Scheme 13: Michael addition reaction of thiazol-4(5H)ones 74 to α’-silyloxyenone 29 [73].
Scheme 14: Elaboration of the thiazolone Michael adducts [73].
Scheme 15: Enantioselective γ-addition of oxazol-4(5H)-ones and thiazol-4(5H)-ones to allenoates promoted by C6...
Scheme 16: Enantioselective γ-addition of thiazol-4(5H)-ones and oxazol-4(5H)-ones to alkynoate 83 promoted by ...
Scheme 17: Proposed mechanism for the C6-catalyzed γ-addition of thiazol-4(5H)-one to allenoates. Adapted from ...
Scheme 18: Catalytic enantioselective α-amination of thiazolones promoted by ureidopeptide like catalysts C5 a...
Scheme 19: Iridium-catalized asymmetric allyllation of substituted oxazol-4(5H)-ones and thiazol-4(5H)-ones pr...
Orthogonal dual thiol–chloroacetyl and thiol–ene couplings for the sequential one-pot assembly of heteroglycoclusters
- Michele Fiore,
- Gour Chand Daskhan,
- Baptiste Thomas and
- Olivier Renaudet
Beilstein J. Org. Chem. 2014, 10, 1557–1563, doi:10.3762/bjoc.10.160
- α-D-ManSH 1 and β-D-GlcNAcSH 2 were prepared from the corresponding bromo peracetyl and chloro peracetyl sugars by treatment with potassium thioacetate followed by de-O-acetylation under standard conditions [24]. Cyclopeptide 3 displaying two orthogonal functionalities, i.e., four lysine residues
Graphical Abstract
Figure 1: Chemical strategy for the construction of heteroglycoclusters.
Scheme 1: Stepwise (Route A) and sequential one-pot (Route B) synthesis of hGCs.
Scheme 2: Synthesis of hGCs 11 and 13.
Figure 2: RP-HPLC profile of the one-pot synthesis of hGC 11 (linear A–B gradient: 5 to 100% B in 20 min, λ =...
Glycosystems in nanotechnology: Gold glyconanoparticles as carrier for anti-HIV prodrugs
- Fabrizio Chiodo,
- Marco Marradi,
- Javier Calvo,
- Eloisa Yuste and
- Soledad Penadés
Beilstein J. Org. Chem. 2014, 10, 1339–1346, doi:10.3762/bjoc.10.136
- transport (a major reservoir for HIV) [29] and some alkyl and alkyloxyalkyl esters of nucleotides or acyclic nucleoside phosphonates have been explored in clinical studies [30]. In order to obtain the ester derivatives, 11-(acetylthio)undecanoic acid, obtained from 11-bromoundecanoic acid and potassium
- thioacetate [31], was reacted with ABC and 3TC in DMF in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and 4-dimethylaminopyridine (DMAP) to obtain the ester derivative in ~75% yield. After purification, the protecting group of the thiol was removed with hydrazine acetate to give the
Graphical Abstract
Figure 1: The prepared lamivudine (3TC) and abacavir (ABC) potential prodrugs and the corresponding 3TC- and ...
Figure 2: Time course release of free 3TC and ABC from the corresponding GNPs in 1 N HCl, detected by HPLC–MS...
Figure 3: Cellular experiments: The two graphs show the percentage of luciferase activity decrease in the pre...
Efficient Cu-catalyzed base-free C–S coupling under conventional and microwave heating. A simple access to S-heterocycles and sulfides
- Silvia M. Soria-Castro and
- Alicia B. Peñéñory
Beilstein J. Org. Chem. 2013, 9, 467–475, doi:10.3762/bjoc.9.50
- of inexpensive potassium thioacetate with both electron-rich and electron-poor aryl iodides under a base-free copper/ligand catalytic system. CuI as copper source affords S-aryl thioacetates in good to excellent yields, by using 1,10-phenanthroline as a ligand in toluene at 100 °C after 24 h. Under
- disulfides and asymmetric diaryl sulfides in good yields. Keywords: catalysis; copper; cross-coupling; potassium thioacetate; sulfur heterocycles; Introduction Aromatic sulfur compounds including sulfides and heterocycles are relevant in chemical, pharmaceutical and materials industries [1][2][3]. As a
- ). In the absence of the catalytic system CuI/1,10-phenanthroline, the aryl iodides bearing the para-acetyl, para-nitro and para-cyano substituents, did not react with potassium thioacetate (1) after 24 h in toluene at 110 °C. These observations rule out the possibility of an aromatic nucleophilic
Graphical Abstract
Figure 1: Examples of some pharmaceutically and chemically important derivatives.
Scheme 1: Synthesis of S-phenyl benzothioate.
Scheme 2: Synthesis of S-phenyl thioacetate.
Scheme 3: Synthesis of 6 by reaction between 7 and 1.
Scheme 4: Reaction of 2-iodobenzoic acid (9) with 1.
Scheme 5: Suggested one-pot synthesis of heterocycle 6.
Scheme 6: Reaction of N-(2-iodophenyl)acetamide (13) with 1.
Scheme 7: Synthesis of 2-methylbenzothiazole (14).
Scheme 8: One-pot three-step synthesis of sulfides. (a) KI/I2; (b) BrCH2Ph; (c) MeI; (d) 4-AnI, CuI/1,10-phen...
Synthesis and antiviral activities of spacer-linked 1-thioglucuronide analogues of glycyrrhizin
- Christian Stanetty,
- Andrea Wolkerstorfer,
- Hassan Amer,
- Andreas Hofinger,
- Ulrich Jordis,
- Dirk Claßen-Houben and
- Paul Kosma
Beilstein J. Org. Chem. 2012, 8, 705–711, doi:10.3762/bjoc.8.79
- -O-acetyl-D-glucopyranosyl)uronate bromide (1) was first reacted with potassium thioacetate in DMF to furnish the known 1-thioacetyl derivative 2 in 82% yield [16]. Subsequent treatment of 2 with sodium methoxide, under controlled conditions at low temperature (−60 °C → −45 °C), provided the
Graphical Abstract
Figure 1: Structure of glycyrrhizin (GL), carbenoxolone (CBX), and spacer analogues.
Scheme 1: Synthesis of methyl 2-haloethyl 1-thio-glucuronide derivatives: (a) 1 M NaOMe, MeOH, −60 °C to −45 ...
Scheme 2: Synthesis of thioalkylglucuronide GA derivatives: (a) DMF, DIPEA, 45–50 °C, 16 h, 79%; (b) TEA, Ac2...
Figure 2: 400 MHz 1H NMR expansion plots of the carbohydrate region of compound 11, recorded at various tempe...
Scheme 3: Synthesis of 3-thioether-bridged glucuronide derivatives: (a) K2CO3, acetone, 60%; (b) 0.8 M NaOMe,...
Asymmetric synthesis of tertiary thiols and thioethers
- Jonathan Clayden and
- Paul MacLellan
Beilstein J. Org. Chem. 2011, 7, 582–595, doi:10.3762/bjoc.7.68
- cyanohydrins, can also be made to undergo SN2 reaction with sulfur nucleophiles [13]. However, substitution of the quaternary α-(sulfonyloxy)nitrile 11 is very slow, and conversion of 11 to 12 with potassium thioacetate in DMF proceeds in only 35% yield after 72 hours. SN2 displacement of the leaving group by
Graphical Abstract
Figure 1: Seven out of the ten top selling drugs in the USA in 2009 contain sulfur. Figures in italics are to...
Figure 2: Naturally occurring organosulfur compounds glutathione and (R)-thioterpineol.
Figure 3: Methods for the synthesis of chiral tertiary thiol 1.
Scheme 1: Preparation of thioethers 4 from α-hydroxy esters.
Scheme 2: Nucleophilic substitution in α-aryl-α-hydroxy esters.
Scheme 3: Preparation of α,α-dialkylthioethers.
Scheme 4: Preparation of α-cyanothioacetate 12.
Scheme 5: Synthesis of (R)-(+)-spirobrassinin.
Scheme 6: Opening of cyclic sulfamidates with thiol nucleophiles.
Scheme 7: Synthesis of androgen 20.
Scheme 8: Synthesis of (+)-BE-52440A.
Scheme 9: The Mitsunobu reaction.
Scheme 10: Mitsunobu substitution at a quaternary centre.
Figure 4: Initially assigned structure of hexacyclinol.
Scheme 11: Preparation of thioether 29.
Scheme 12: Thioethers 33 prepared from phosphinites 31.
Scheme 13: Preparation of enantiomerically pure thiol 39.
Scheme 14: Thioethers prepared by a modified Mitsunobu reaction.
Scheme 15: Nucleophilic conjugate addition.
Scheme 16: Asymmetric addition to cyclic enones.
Scheme 17: Preparation of thioether 45.
Scheme 18: Catalytic kinetic resolution of the enantiomers of enone 46.
Scheme 19: Organocatalytic conjugate addition to nitroalkenes 49.
Scheme 20: Preparation of β-amino acid 54.
Scheme 21: Sulfur migration within oxazolidine-2-thiones 56.
Scheme 22: Preparation of thiols 62 by self-regeneration of stereocentres.
Scheme 23: Synthesis of (5R)-thiolactomycin.
Scheme 24: Preparation of tertiary thiols and thioethers via α-thioorganolithiums.
Scheme 25: Diastereoselective methylation of organolithium 71.
Scheme 26: Addition to lithiated thiocarbamate 75.
Scheme 27: Configurational lability in unhindered α-lithiothiocarbamates.
Scheme 28: Configurational stability in bulky α-lithiothiocarbamates.
Scheme 29: Asymmetric functionalisation of secondary benzylic thiocarbamates.
Scheme 30: Methylation of lithioallyl thiocarbamates.
Scheme 31: Asymmetric preparation of tertiary allylic thiols.
Scheme 32: Asymmetric preparation of thiols 96 by aryl migration in lithiated thiocarbamates.
Convergent syntheses of LeX analogues
- An Wang,
- Jenifer Hendel and
- France-Isabelle Auzanneau
Beilstein J. Org. Chem. 2010, 6, No. 17, doi:10.3762/bjoc.6.17
- glycoside 29 was in turn used as a precursor to the 6-azidohexyl, 6-acetylthiohexyl and 6-thiobenzylhexyl trisaccharides 30–32 (Scheme 3). Thus, nucleophilic displacement of the chloride with sodium azide or potassium thioacetate was carried out in DMF at 80 °C and provided the 6-azidohexyl and 6
Graphical Abstract
Figure 1: Structure of Lex analogues 1–3.
Figure 2: Monosaccharide glycosyl acceptors (4–6) and donors (7–9) used in this study.
Scheme 1: Synthesis of monosaccharide glycosyl acceptors 4–6.
Scheme 2: Synthesis of the galactosyl donor 8.
Scheme 3: Convergent synthesis of trisaccharides 29–32.
Scheme 4: Proposed mechanism for the desulfurization of thioacetate 31 under dissolving metal conditions.
