Ring closing metathesis
Phyllostictine A ring assembly via ring closing metathesis
... 61 60 Scheme 2.9 By extending this methodology to RCM, this offers a potential route to the phyl- lostictines. Forming tetrasubstituted double bonds by RCM, although uncommon, is a known process. Grubbs and co-workers ...
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SYNTHESIS OF SOME CYCLITOLS AND AMINOCYCLITOLS BY USING RING CLOSING METATHESIS
... to ring closing metathesis using 5 mol% Grubbs 2 nd generation catalyst in DCM to give cyclopentene derivative 40 as major isomer along with minor isomer ...
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Highly functionalized piperidines via ring-closing metathesis of dehydroamino acids
... Non-proteinogenic α,β-unsaturated dididehydroamino esters are widespread in nature and exhibit a wide range of biological activities. Many chemists have been inspired by these important bioactivities and also due to ...
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Synthesis of fluoride- and trifluoromethyl- substituted heterocycles via ring-closing metathesis
... (ring-closing metathesis, RCM) te gebruiken als algemene methode om fluoride- en trifluormethyl-gesubstitueerde olefinen om te zetten in de overeenkomstige gefluoreerde ...
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Synthesis of cage heterocycles containing tetrahydrofuran and pyran ring system via Grignard addition and ring-closing metathesis
... Several cage compounds containing tetrahydrofuran and pyran rings have been reported by using the Grignard addition and ring-closing metathesis as key steps. Cage hemiketal derivatives have been ...
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Toward a simulation approach for alkene ring-closing metathesis : scope and limitations of a model for RCM
... the ring-closing metathesis (RCM) reaction of diethyl diallylma- lonate 7 has been evaluated over a wider range of conditions, to assess its suitability for new ...
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Diastereoselective synthesis of trisubstituted olefins using a silicon-tether ring-closing metathesis strategy
... silicon-tether ring-closing metathesis reac- ...the metathesis substrates, we designed a novel Peterson olefination reaction that enabled direct access to ...
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Exploring the ring-closing metathesis for the construction of the solomonamide macrocyclic core: identification of bioactive precursors
... 2.3. Ring-Closing Metathesis at the C3-C4 ...5-membered ring chelate between the ruthenium carbene and the carbonyl group of the amide (intermediate A), which renders the metallacyclobutane ...
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Ring-closing metathesis of functionalized olefins. Key to heterocyclic building blocks and natural products
... Ring-closing metathesis of α -alkoxyacrylates Subjection of a different primary alcohol (i.e. benzyl alcohol 8) to the Pd(0)- catalyzed conditions, employing either 4a or c, resulted in the ...
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New Routes to 2,5-Disubstituted Tetrahydropyrans and P-Stereogenic Heterocycles via Ring-Closing Metathesis
... Synthesis of 2,5-disubstituted tetrahydropyrans in a racemic fashion was achieved via Grignard addition, O-alkylation, ring-closing metathesis and hydrogenation. Using this route, seven potential ...
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Mapping the potential energy surfaces for ring-closing metathesis reactions of prototypical dienes by electronic structure calculations
... for ring-closing metathesis reactions of a series of simple a,w-dienes which lead to 5–10 membered ring products, have been explored using density functional theory ...
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Methods for Enhancing Ring Closing Metathesis Yield in Peptides: Synthesis of a Dicarba Human Growth Hormone Fragment
... The formation of large rings in cyclic peptides, however, is often low yielding due to undesirable physicochemical affects arising from the formation of secondary structures, intermolecular aggregation and an inability ...
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Ring closing metathesis reactions of α methylene β lactams : application to the synthesis of a simplified phyllostictine analogue with herbicidal activity
... a Ring closing metathesis (RCM) reactions of -methylene--lactams are used to construct strained 11- and 12-membered macrocycles that mimic key structural elements of phyllostictine ...
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Synthesis of Enantiopure Oxygen- and Nitrogen-Containing Heterocycles by Diastereoselective Ring-Closing Metathesis Reaction in Perhydro-1,3-benzoxazine Derivatives
... Diastereoselective ring-closing metathesis reactions on chiral trienic perhydro-1,3-benzoxazines derived from (-)-8-aminomenthol featuring two diastereotopic olefin chains is ...
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STEREOSELECTIVE TOTAL SYNTHESIS OF (-)-ASPINOLIDE, SYRIBUTINS, RING-CLOSING METATHESIS APPROACH TO THE SYNTHESIS OF ILEXLACTONE AND SYNTHESIS OF STRUCTURALLY DIVERSE COMPOUNDS VIA BAYLIS-HILLMAN REACTION
... catalyzed ring-closing metathesis has been the subject of much attention in the recent years, and the development of ruthenium carbene complexes by Grubbs’ and co-workers is particularly notable ...
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Cross Metathesis and Ring-Closing Metathesis Reactions of Modified Amino Acids and Peptides.
... The organic layer was washed with aqueous saturated sodium bicarbonate (10 mL), saturated ammonium chloride (10 mL), and saturated brine solution (10 mL), the organic [r] ...
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Ring-closing metathesis towards a formal synthesis of Taxol
... eight-membered ring in the taxoid skeleton exemplifies the need for efficient and high yielding methodologies for its ...B ring using ...AB ring system starting from ...
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Central core Uprolides a survey of some ring closing metathesis approaches
... The residue was purified by chromatography (1:1 petroleum ether/ethyl acetate) followed by crystallization to give diol 7 (3.1 g, 25.4% overall) as colorless solid.. DCM was [r] ...
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Synthesis of a Ribose-Incorporating Medium Ring Scaffold via a Challenging Ring-Closing Metathesis Reaction.
... medium ring formation as the tri-TMS-protected substrate (1f) did not ...fused ring protecting group on the tetrahydrofuran diol gave a very small yield of medium ring product which was an ...
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Synthesis of benzo-fused heterocycles using isometerization and ring-closing metathesis reactions
... 142e 2 M 180 86 * not isolated, used directly in the next step Overall, the yields of the Claisen rearrangements were poor to moderate, with an average yield of just 62 %. The heating methodology employed does not, ...
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