| 1. |
- Adeyemi, Ahmed, et al.
(författare)
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Regio- and Stereoselective Synthesis of Spirooxindoles via Mizoroki-Heck Coupling of Aryl Iodides
- 2019
-
Ingår i: Synlett. - : GEORG THIEME VERLAG KG. - 0936-5214 .- 1437-2096. ; 30:1, s. 82-88
-
Tidskriftsartikel (refereegranskat)abstract
- A method for highly regio- and stereoselective intramolecular Mizoroki-Heck 5- exo cyclization of aryl iodides to the corresponding spirooxindoles has been developed. Electron-rich and electron-deficient aryl iodide precursors were selectively ring-closed with high stereoselectivity and good yields. The double-bond position in the cyclopentene ring was controlled by careful choice of reaction conditions. These rare spiro compounds were further functionalized to rigidified unnatural amino acid derivatives by a subsequent gas-free Pd(0)-catalyzed alkoxycarbonylation, followed by selective O - and N -deprotections.
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| 2. |
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| 3. |
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| 4. |
- Akkarasamiyo, Sunisa, et al.
(författare)
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Synthesis of (Z)-Cinnamate Esters by Nickel-Catalyzed Stereoinvertive Deoxygenation of trans-3-Arylglycidates
- 2022
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 33:14, s. 1353-1356
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Tidskriftsartikel (refereegranskat)abstract
- We report a stereoinvertive deoxygenation of trans-3-arylglycidates as an alternative route to access thermodynamically less stable (Z)-cinnamate esters by using nickel triflate and triphenylphosphine. Broad functional-group tolerance was observed, with trans-3-arylglycidates containing methyl, methoxy, halo, or nitro groups affording the corresponding (Z)-cinnamate esters in high yields and with moderate to high E/Z ratios.
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| 5. |
- Al-Smadi, Derar, 1983-, et al.
(författare)
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Synthesis of substrates for aldolase-catalyzed reactions : A comparison of methods for the synthesis of substituted phenylacetaldehydes
- 2018
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 29:9, s. 1187-1190
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Tidskriftsartikel (refereegranskat)abstract
- Methods for the synthesis of phenylacetaldehydes (oxidation, one-carbon chain extension) were compared by using the synthesis of 4-methoxyphenylacetaldehyde as a model example. Oxidations of 4-methoxyphenylethanol with activated DMSO (Swern oxidation) or manganese dioxide gave unsatisfactory results; whereas oxidation with 2-iodoxybenzoic add (IBX) produced 4-methoxyphenylacetaldehyde in reasonable (75%) yield. However, Wittig-type one-carbon chain extension with methoxymethylene-triphenylphosphine followed by hydrolysis gave an excellent (81% overall) yield of 4-methoxyphenylacetaldehyde from 4-methoxybenzaldehyde (a cheap starting material). This approach was subsequently used to synthesise a set of 10 substituted phenylacetaldehydes in good to excellent yields.
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| 6. |
- Axelsson, Anton, 1991, et al.
(författare)
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Biomimetic Oxidative Carbene Catalysis: Enabling Aerial Oxygen as a Terminal Oxidant
- 2017
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 1437-2096 .- 0936-5214. ; 28:08, s. 873-878
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Tidskriftsartikel (refereegranskat)abstract
- Oxidative carbene catalysis is a quickly growing field in organic synthesis. However, these catalytic protocols traditionally rely on the stoichiometric addition of a high-molecular-weight oxidant, providing these reactions with a high E-factor. Here, we review efforts to replace high-molecular-weight oxidants with oxygen using a biomimetic system of coupled electron-transfer mediators. Two reactions are discussed: the aerobic oxidative esterification of aldehydes and the aerobic oxidative NHC-catalyzed enantioselective formation of dihydropyranones.
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| 7. |
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| 8. |
- Bhattacharyya, S, et al.
(författare)
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Synthesis of rigid polycyclic secondary diamines: Bis-(2,3:6,7-iminodimethylene)anthracene and bis-(2,3:6,7-iminodimethylene)-9,10-dicarboxyethenoanthracene.
- 2003
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; :9, s. 1361-1363
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Tidskriftsartikel (refereegranskat)abstract
- The synthesis of two rigid polycyclic secondary diamines, bis-(2,3:6,7-iminodimethylene)anthraceneand bis-(2,3:6,7-iminodimethylene)-9,10-dicarboxyethenoanthracene,by means of Diels-Alder reaction between 1,2,4,5-tetra(dibromo?methyl)benzeneand maleimides followed by imide reduction, is described. Furthermore,these two cyclic secondary diamines undergo acylation with N-protectedamino acids, thus providing functionalized, amphiphilic, and chiralbuilding blocks for incorporation into supramolecular systems.
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| 9. |
- Borah, Raju Kumar, et al.
(författare)
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Copper Oxide Nanoparticles as a Mild and Efficient Catalyst for N-Arylation of Imidazole and Aniline with Boronic Acids at Room Temperature
- 2017
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 28:10, s. 1177-1182
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Tidskriftsartikel (refereegranskat)abstract
- The present work describes the excellent catalytic activity of copper(II) oxide nanoparticles (NPs) towards N-arylation of aniline and imidazole at room temperature. The copper(II) oxide NPs were synthesized by a thermal refluxing technique and characterized by FT-IR spectroscopy; powder XRD, SEM, EDX, TEM, TGA, XPS, BET surface area analysis, and particle size analysis. The size of the NPs was found to be around 12 nm having a surface area of 164.180 m(2) g(-1). The catalytic system was also found to be recyclable and could be reused in subsequent catalytic runs without a significant loss of activity.
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| 10. |
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| 11. |
- Brown, Michael, et al.
(författare)
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Synthesis of New Chiral Diaryliodonium Salts
- 2015
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 26:11, s. 1573-1577
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Tidskriftsartikel (refereegranskat)abstract
- A structurally diverse range of chiral diaryliodonium salts have been synthesised which have potential application in metal-free stereoselective arylation reactions.
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| 12. |
- Bunrit, Anon, et al.
(författare)
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Nucleophilic Substitution of the Hydroxyl Group in Stereogenic Alcohols with Chirality Transfer
- 2016
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 27:2, s. 173-176
-
Tidskriftsartikel (refereegranskat)abstract
- A brief overview of the development of direct substitution of the hydroxyl (OH) group of alcohols in our research group is presented. By applying a BrOnsted acid, an intramolecular substitution of the OH group in stereogenic alcohols with chirality transfer was achieved. Noteworthy, the intramolecular substitution has a wide scope in respect to both the nucleophile and also the nucleofuge. A mechanistic study by both experiments and DFT calculations revealed a unique reaction pathway in which the BrOnsted acid operates in a bifunctional manner to promote an S(N)2-type reaction mechanism.
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| 13. |
- Burke, Anthony, et al.
(författare)
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Immobilization of Functionalized epi-Cinchonine Organocatalysts on Controlled Porous Glass-Beads : Applications in Batch and Continuous Flow
- 2022
-
Ingår i: Synlett. - : Georg Thieme Verlag. - 0936-5214 .- 1437-2096. ; 33:17, s. 1756-1762
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Tidskriftsartikel (refereegranskat)abstract
- A well-known Squaramide-Cinchonine organocatalyst was immobilized in a controlled way onto three types of commercial porous glass beads EziGTM (EziG OPAL, EziG Amber and EziG Coral) and applied in asymmetric Michael reactions. The performance of the immobilized catalysts was evaluated under batch and continuous flow conditions showing promising results in both approaches. In batch reactions, 0.8 and 1.6 mol% of the immobilized cinchonine-squaramide provided the products with excellent yields (up to 99%) and enantioselectivities (up to 99% ee). These excellent results were also verified in the case of continuous flow reactions, where also 0.8 and 1.6 mol% of the catalyst immobilized onto the glass beads afforded the product with extraordinary yields (up to 99%) and very high enantioselectivities (up to 97% ee). The immobilized catalysts could be recycled (up to 7 cycles) using both approaches.
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| 14. |
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| 15. |
- Chitsomkhuan, Saranya, et al.
(författare)
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Copper(II) Triflate Catalyzed Rearrangement of Amino 2,3-Epoxides to α-Amino Ketones
- 2024
-
Ingår i: Synlett. - 0936-5214 .- 1437-2096.
-
Tidskriftsartikel (refereegranskat)abstract
- α-Amino ketones were synthesized by a Meinwald rearrangement of biomass-based amino epoxides using copper(II) triflate as a catalyst. The regioselectivity of the rearrangement can be rationalized in terms of the reaction proceeding via the most stable carbocationic intermediate to give various α-amino α′-aryl ketones in moderate to good yields. This is an attractive method to prepare α-amino ketones using a benign and inexpensive catalyst.
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| 16. |
- Colas, Kilian, 1990-, et al.
(författare)
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Iterative Synthesis of Pluripotent Thioethers through Controlled Redox Fluctuation of Sulfur
- 2018
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 29:10, s. 1329-1333
-
Tidskriftsartikel (refereegranskat)abstract
- Target- and diversity-oriented syntheses are based on diverse building blocks, whose preparation requires discrete design and constructive alignment of different chemistries. To enable future automation of the synthesis of small molecules, we have devised a unified strategy that serves the divergent synthesis of unrelated scaffolds such as carbonyls, olefins, organometallics, halides, and boronic esters. It is based on iterations of a nonelectrophilic Pummerer-type C-C coupling enabled by turbo -organomagnesium amides that we have recently reported. The pluripotency of sulfur allows the central building blocks to be obtained by regulating C-C bond formation through control of its redox state.
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| 17. |
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| 18. |
- Cumpstey, Ian, et al.
(författare)
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Investigation of Coupling Reactions for the Synthesis of Valienamine Pseudodisaccharides
- 2011
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; :12, s. 1701-1704
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Tidskriftsartikel (refereegranskat)abstract
- Amine-linked pseudodisaccharides based on valienamine were synthesised by C-N bond-forming reactions between valienol-derived C-1 electrophiles and carbohydrate nitrogen nucleophiles. Palladium-catalysed coupling with trichloroacetimidate leaving groups, Mitsunobu reactions with a nosylamide nucleophile, and alkylation of amines by C-1 bromides were investigated.
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| 19. |
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| 20. |
- Dahlén, Kristian, 1973, et al.
(författare)
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A scaffold approach to 3,6,8-trisubstituted flavones
- 2006
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; :6, s. 897-900
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Tidskriftsartikel (refereegranskat)abstract
- An efficient synthetic approach to 3,6,8-trisubstituted flavone scaffolds has been developed based on Pd-mediated coupling reactions.
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| 21. |
- Danelius, Emma, et al.
(författare)
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Insight into β-Hairpin Stability: Interstrand Hydrogen Bonding
- 2013
-
Ingår i: Synlett : Accounts and Rapid Communications in Synthetic Organic Chemistry. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 24:18, s. 2407-2410
-
Tidskriftsartikel (refereegranskat)abstract
- For evaluation of the role of interstrand hydrogen bonding for β-hairpin stability, two cyclic peptides differing only in side chain hydroxy-to-methyl substitution were designed and synthesized on solid phase following the Fmoc-t-Bu-Trt protection strategy. Subsequent to cyclization in solution, combined computational and experimental ensemble analysis revealed higher conformational stability of the peptide capable of interstrand hydrogen bonding.
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| 22. |
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| 23. |
- Hirner, Sebastian, et al.
(författare)
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Microwave-Assisted Rearrangement of Vinylaziridines to 3-Pyrrolines : Formal Synthesis of (-)-Anisomycin
- 2005
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; :20, s. 3099-3102
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Tidskriftsartikel (refereegranskat)abstract
- An efficient microwave-assisted rearrangement of activated vinylaziridines to 3-pyrrolines is described. The rearrangement proceeds in good to excellent yields and is mediated by NaI or LiI in MeCN at elevated temperatures. The synthetic utility of this reaction is shown in an efficient formal total synthesis of the antibiotic (-)-anisomycin.
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| 24. |
- Hong, S, et al.
(författare)
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Stereoselective Synthesis of Maresin-like Lipid Mediators
- 2019
-
Ingår i: Synlett : accounts and rapid communications in synthetic organic chemistry. - : Georg Thieme Verlag KG. - 0936-5214. ; 30:3, s. 343-347
-
Tidskriftsartikel (refereegranskat)abstract
- 14S,22-Dihydroxy-docosa-4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acid (maresin-L1) and 14R,22-dihydroxy-docosa-4Z,7Z,10Z, 12E,16Z,19Z-hexaenoic acid (maresin-L2) were chemically synthesized. They were identical to activated macrophage-produced counterparts and their total synthesis was highly stereoselective, as revealed by chiral LC-UV-MS/MS analysis. The synthesis involved the following steps: (1) kinetic resolution of a racemic allylic alcohol by the asymmetric epoxidation; (2) transformation of the epoxy alcohol to γ-hydroxyenal derivative; and (3) the Wittig reaction to furnish the Z-olefin.
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| 25. |
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| 26. |
- Hussain, Munawar, et al.
(författare)
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Domino Twofold Heck/6π-Electrocyclization Reactions of 1,2-Dihaloalkenes
- 2012
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; :19, s. 2735-2744
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Tidskriftsartikel (refereegranskat)abstract
- Domino twofold Heck/6 pi-electrocyclization reactions of 1,2-dihaloalkenes allow for a convenient synthesis of benzene derivatives. In recent years, this strategy has been applied to various 1,2-dihalogenated carbocyclic alkenes and heterocycles, and a variety of benzo-fused ring systems have been prepared. The electrocyclization reactions proceed well for five-membered, but not for six-membered heterocycles.
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| 27. |
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| 28. |
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| 29. |
- Larsson, Johanna, et al.
(författare)
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Selective Activation of Arylboronate or Aryne Reactivity as a Versatile Postfunctionalization Strategy
- 2016
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 27:7, s. 969-976
-
Tidskriftsartikel (refereegranskat)abstract
- This review discusses the preparation and orthogonal reactivity of boryl ortho-silyl(hetero)aryl triflates as precursors for arynes. These triflates undergo a wide variety of selective reactions of either the boronate or aryne component. Activation of the boronate group affords diverse (hetero)aryne precursors, whereas aryne activation and capture gives previously difficult-to-access arylboronates, all starting from the same set of common starting materials. Thus, the boronate and aryne functionality can be used for their mutual postfunctionalization with unprecedented flexibility.
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| 30. |
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| 31. |
- Lennartsson, Anders, 1980, et al.
(författare)
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A Convenient Route to 2-Bromo-3-chloronorbornadiene and 2,3-Dibromonorbornadiene
- 2015
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 1437-2096 .- 0936-5214. ; 26:11, s. 1501-1504
-
Tidskriftsartikel (refereegranskat)abstract
- Substituted norbornadienes are useful in a wide range of applications, including molecular solar-thermal (MOST) energy storage systems. An important precursor for 2,3-substituted norbornadienes is 2-bromo-3-chloronorbornadiene, where the two halogen atoms can be substituted selectively through two consecutive Suzuki cross-coupling reactions. Previous routes to 2-bromo-3-chloronorbornadiene have used 1,2-dibromoethane as a brominating agent, a substance known to be carcinogenic and the use of which is restricted in certain countries. Herein is reported a one-pot route to 2-bromo-3-chloronorbornadiene in 50% yield using p-toluenesulfonyl bromide as a bromine source. In addition, the procedure has been adapted to allow synthesis of 2,3-dibromonorbornadiene in 37% yield.
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| 32. |
- Ljungdahl, N., et al.
(författare)
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The development of an asymmetric Nicholas reaction using chiral phosphoramidite ligands
- 2008
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 1437-2096 .- 0936-5214. ; :3, s. 394-398
-
Tidskriftsartikel (refereegranskat)abstract
- An asymmetric version of the Nicholas reaction involving the use of chiral phosphoramidite ligands has been developed. Treatment of a cobalt carbonyl complexed propargylic alcohol with two equivalents of the chiral ligand, followed by reaction with a silyl enol ether in the presence of a Lewis acid, afforded, after decomplexation, the desired product in up to 74% ee for the carbon-carbon bond forming step. © Georg Thieme Verlag Stuttgart.
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| 33. |
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| 34. |
- Mai, Juri, et al.
(författare)
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The Fascinating World of Phosphanylphosphonates : From Acetylenic Phosphaalkenes to Reductive Aldehyde Couplings
- 2019
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 30:16, s. 1867-1885
-
Tidskriftsartikel (refereegranskat)abstract
- This account highlights the versatility of phosphanylphosphonates, which can be used for the preparation of phosphorus-containing π-systems and as reagents for the reductive coupling of carbonyl compounds to alkenes. Phosphanylphosphonates with metal fragments coordinated to the P-lone pair have been known for a long time and they have been used for the synthesis of phosphaalkenes by means of the phospha-Horner–Wadsworth–Emmons reaction. With the original aim of incorporating phosphorus heteroatoms into classical all-carbon ethynylethene scaffolds, we entered the field of phosphanylphosphonates with the discovery that these compounds engage in complex cascade reactions with acetylenic ketones, forming 1,2-oxaphospholes, cumulenes, and bisphospholes. Later, we synthesized the first metal-free phosphanylphosphonate, which reacts with aldehydes to yield phosphaalkenes, but gives phospholones when diacetylenic ketones are used as substrates. In the final part of the account, we outline our discovery and the development of an unprecedented carbonyl–carbonyl cross-coupling reaction. This protocol offers a straightforward method for the synthesis of nonsymmetric 1,2-disubstituted alkenes directly from two dissimilar aldehydes.1. Combining Acetylenes with Phosphaalkenes2. Synthetic Examples of Acetylenic Phosphaalkenes3. The Phospha-Horner–Wadsworth–Emmons Approach to Phosphaalkenes3.1. Metal-Coordinated Phosphanylphosphonates3.2. Mechanism of the Phospha-Horner–Wadsworth–Emmons Reaction3.3. The First Metal-Free Phosphanylphosphonate and Its Reactivity with Aldehydes4. Reactions with Acetylenic Ketones4.1. Metal-Coordinated Phosphanylphosphonate and Monoacetylenic Ketones4.2. Metal-Coordinated Phosphanylphosphonate and Diacetylenic Ketones4.3. Metal-Free Phosphanylphosphonate and Diacetylenic Ketones5. Metal-Free Phosphanylphosphonate as a Coupling Reagent for Aldehydes6. E-Alkenes by the Reductive Coupling of Two Aldehydes7. Conclusions and Outlook
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| 35. |
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| 36. |
- Margarita, Cristiana, et al.
(författare)
-
Catalytic Dehydrative Transformations Mediated by Moisture-Tolerant Zirconocene Triflate
- 2023
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 34:14, s. 1678-1684
-
Tidskriftsartikel (refereegranskat)abstract
- Zirconocene triflate is a powerful moisture-tolerant catalyst for activation of C O bonds in carboxylic acids and alcohols in the absence of water scavenging techniques. Herein, an overview of the use of this robust metal complex for direct amidation, esterification, and etherification is presented, along with a discussion on mechanistic aspects of the transformations and the catalyst class.
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| 37. |
- Mendoza, Abraham, et al.
(författare)
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Chemical Innovation through Ligand Total Synthesis
- 2016
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 27:12, s. 1753-1759
-
Tidskriftsartikel (refereegranskat)abstract
- Natural products are an abundant source of synthetic challenges that foster crucial breakthroughs in organic chemistry. Despite the superior complexity of these targets, ligand total synthesis can inspire solutions to unsolved chemical problems and provide access to creative catalyst designs. This Synpacts article presents a comparative analysis of natural and ligand total synthesis to provide a context for our recent research and motivate the importance of future undertakings in this area.
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| 38. |
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| 39. |
- Micova, Julia, et al.
(författare)
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Synthesis of 4-Carbamoyl-2-oxazolidinones C-4-Linked with a Saccharide Moiety via Bucherer-Bergs Reaction of Hexofuranos-5-uloses
- 2002
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 1437-2096 .- 0936-5214. ; 2002:10, s. 1715-1717
-
Tidskriftsartikel (refereegranskat)abstract
- Application of the Bucherer-Bergs reaction to 6-O-unprotected hexofuranos-5-uloses led to the formation of 4-carbamoyl-2-oxazolidinones C-4-linked with a carbohydrate moiety instead of expected carbohydrate-C-5-linked hydantoin (imidazolidin-2,4-dione) derivatives. Starting from hexofuranos-5-uloses having all hydroxyl groups suitably protected, only corresponding saccharide-linked hydandoins were obtained.
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| 40. |
- Moberg, Christina, et al.
(författare)
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Enantioenriched Acylated Cyanohydrins : Synthesis and Analysis
- 2010
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; :3, s. 355-367
-
Tidskriftsartikel (refereegranskat)abstract
- The addition of acyl cyanides to prochiral aldehydes catalyzed by a chiral Lewis acid and an achiral Lewis base produces highly enantioenriched O-acylated cyanohydrins. alpha-Keto esters undergo the same type of addition, although via a different mechanism in which the enantioselectivity originates from a chiral Lewis base. In the presence of a biocatalyst, the minor, undesired enantiomer obtained in the reactions with aldehydes can be selectively hydrolyzed to re-form the starting aldehyde, permitting the reaction to be run in a cyclic manner. The minor-enantiomer recycling results in an essentially enantiopure product. Selective enzymatic hydrolysis is also a key step in high-throughput analysis of conversions and enantiomeric ratios.
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| 41. |
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| 42. |
- Njogu, Rachael E.N., et al.
(författare)
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Electronically Divergent Triscyclometalated Iridium(III) 2-(1-naphthyl)pyridine Complexes and Their Application in Three-Component Methoxytrifluoromethylation of Styrene
- 2019
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 30:7, s. 792-798
-
Tidskriftsartikel (refereegranskat)abstract
- A systematic study of the photophysical and electrochemical properties of triscyclometalated homoleptic iridium(III) complexes based on 2-(1-naphthyl)pyridine (npy) ligands is presented. A systematic investigation of ligand substitution patterns showed an influence on the lifetime of the excited state, with slight changes in the absorption and emission spectral features. Specifically, the emission lifetime of a complex of an npy ligand substituted with a strongly electron-withdrawing trifluoromethyl group was longer than that of the corresponding complex with the electronically nonperturbed ligand (3.7 μs versus 1.5 μ s). Electronically complementary ligands and complexes with orthogonal configurations showed slightly shorter excited state lifetimes compared with unsubstituted npy (1.4-3.0 μs). All complexes displayed reversible or quasireversible redox-couple processes, with the complex of the trifluoromethylated ligand showing the highest ground-state oxidation potential E 1/2 ox [Ir(III)/Ir(IV) = 0.95 V vs. SCE in CH 2 Cl 2 ]. This study showed that these complexes can be used as efficient photoredox catalysts, as demonstrated by their application in a regioselective methoxytrifluoromethylation in which the npy complexes showed equal or better performance compared with the archetypical photo redox catalyst tris[2-phenylpyridinato]iridium(III).
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| 43. |
- Odell, Luke R., et al.
(författare)
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Molybdenum Hexacarbonyl Mediated CO Gas-Free Carbonylative Reactions
- 2012
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; :5, s. 685-698
-
Tidskriftsartikel (refereegranskat)abstract
- This Account summarizes predominately our own experiences in developing microwave-heated palladium-catalyzed Mo(CO)6-mediated gas-free carbonylative reactions, although contributions from other groups, including non-palladium-catalyzed examples, have also been covered. Presented reactions include amino-, amido-, and alkoxycarbonylations as well as carbonylative cyclizations and carbonylative cross-couplings, using Mo(CO)6 as a solid source of CO. The methodology was developed mainly for rapid small-scale applications, avoiding the problematic use of gaseous CO in a standard laboratory. In most cases, the reported Mo(CO)6-mediated carbonylations were conducted in sealed vessels and with reaction times of less than 1 hour. The Account also highlights relevant applications in medicinal and high-speed chemistry.
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| 44. |
- Ohberg, L., et al.
(författare)
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One-pot three-step solution phase syntheses of thiohydantoins using microwave heating
- 2001
-
Ingår i: Synlett. - 0936-5214 .- 1437-2096. ; :12, s. 1893-1896
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- An efficient one-pot three-step solution phase protocol suitable for library syntheses of thiohydantoins was developed. The reactions included are in the following order, Negishi or Suzuki C-C coupling reactions, reductive amination and finally a cyclisation reaction. Protocols using a solid supported reagent and protocols suitable for combinatorial chemistry were developed, all including microwave heating.
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| 45. |
- Peters, Bram B. C., et al.
(författare)
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Enantioselective Synthesis of α-Chiral Amides by Catalytic Hydrogenation with Iridium N,P-Complexes
- 2023
-
Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 34:12, s. 1519-1523
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Tidskriftsartikel (refereegranskat)abstract
- The catalytic asymmetric hydrogenation of olefins constitutes a powerful method for the preparation of chiral compounds. A series of prochiral unsaturated amides were efficiently reduced with high enantioselectivities by means of an iridium N,P-complex-catalyzed hydrogenation. Its application in the synthesis of fenpropidin and the possibility of using isomeric mixtures of starting materials are attractive features of the method.
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| 46. |
- Pilarski, Lukasz T., 1981-
(författare)
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Young Career Focus : Dr. Lukasz T. Pilarski (Uppsala University, Sweden)
- 2017
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Ingår i: Synlett. - : GEORG THIEME VERLAG KG. - 0936-5214 .- 1437-2096. ; 28:8, s. A83-A85
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background and Purpose. SYNFORM regularly meets young up-and-coming researchers who are performing exceptionally well in the arena of organic chemistry and related fields of research, in order to introduce them to the readership. This Young Career Focus presents Dr. Lukasz T. Pilarski (Uppsala University, Sweden).
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| 47. |
- Shatskiy, Andrey, 1989-, et al.
(författare)
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Photoredox-Enabled Decarboxylative Synthesis of Unnatural α-Amino Acids
- 2022
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 33:2, s. 109-115
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Tidskriftsartikel (refereegranskat)abstract
- Recently, development of general synthetic routes to unnatural α-amino acids has gained significant momentum, driven by the high demand for such building blocks in fundamental research within molecular and structural biology, as well as for development of new pharmaceuticals. Herein, we highlight the recent progress in employing photoredox-mediated synthetic methods for accessing unnatural α-amino acids with a focus on various decarboxylative radical-based strategies.
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| 48. |
- Shirani, Hamid, et al.
(författare)
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New routes to 3-(Arylthio)indoles : Application to the synthesis of the 3,3 '-bis(indolyl) sulfone core of the marine alkaloid echinosulfone A
- 2006
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; :15, s. 2459-2463
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Tidskriftsartikel (refereegranskat)abstract
- A new approach to 3-(arylthio)indoles and related compounds has been developed, based on the reactions of aryl Grignard reagents or lithiated heteroaroinatics with a phenylsulfonyl-protected 3,3'-bis(indolyl) disulfide. In addition, a rational approach to the 3,3'-bis(indolyl) sulfone core of the alkaloid echinosulfone A has been accomplished, involving treatment of a 3-lithioindole with bis(phenylsulfonyl) sulfide as the key step.
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| 49. |
- Smitt, Olof, et al.
(författare)
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First Total Synthesis of (-)-1(10),5-Germacradien-4-ol
- 2002
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Ingår i: Synlett. - : Georg Thieme Verlag KG. - 0936-5214 .- 1437-2096. ; 2002:8, s. 1273-1276
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a total synthesis of (-)-1(10),5-germacradien-4-ol, a constituent of the needles of Scots pine and of the defence secretion from the larvae of the pine sawfly. The synthesis uses a strategy based on an intramolecular alkylation to form an unsaturated monocyclic 10-membered ring.
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| 50. |
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