Ring closing metathesis natural product synthesis

Keywords Ruthenium-carbenes, Ruthenium-allenylidenes, Ring closing metathesis, Natural product synthesis, Fine chemicals. 

Negishi E, Tan Z (2005) Diastereoselective, Enantioselective, and Regioselective Carbo-alumination Reactions Catalyzed by Zirconocene Derivatives. 8 139-176 Netherton M, Fu GC (2005)Palladium-catalyzed Cross-Coupling Reactions of Unactivated Alkyl Electrophiles with Organometallic Compounds. 14 85-108 NicolaouKC, KingNP, He Y (1998) Ring-Closing Metathesis in the Synthesis of EpothUones and Polyether Natural Products. 1 73-104 Nishiyama H (2004) Cyclopropanation with Ruthenium Catalysts. 11 81-92 Noels A, Demonceau A, Delaude L (2004) Ruthenium Promoted Catalysed Radical Processes toward Fine Chemistry. 11 155-171... 

Ring-Closing Metathesis in the Synthesis of Epothilones and Polyether Natural Products... 

Nicolaou KC, King NP, He Y (1998) Ring-Closing Metathesis in the Synthesis of Epothilones and Polyether Natural Products. 1 73 -104 Nishiyama H (2004) Cyclopropanation with Ruthenium Catalysts. II 81-92... 

Nicolaou, K. C., King, N. P., He, Y. Ring-closing metathesis in the synthesis of epothilones and polyether natural products. Top. 

The synthesis of manzamine A by Martin and co-workers using olefin metathesis - was one of the earliest demonstrations - of how this reaction could be applied as a strategy in natural product synthesis. The ring-closing metathesis in this synthesis was conducted with Schrock s molybdenum catalyst, as shown in Equation 21.8. 

A surprising result was found during an attempt to carry out a ring-closing metathesis during a synthesis of 3-deacetoxy-6-deacetylcalicophirin, a marine natural product (Scheme 8.122). When the triene 8.456... 

The total synthesis of alkaloid (+)-lycoricidine reported by Yadav et al. represents a further application of the sequence domino reductive fragmentation/allylation followed by ring-closing metathesis in the synthesis of bioactive natural products [42], Thus, reaction of co-iodoglycoside 29 with zinc/allyl bromide in THF/HjO afforded diene 30 (87%, dr 85 15). Ring-closing metathesis of diene 30 followed by acetylation furnished cyclohexene 31. Treatment of the acetate 31 with PhINTs in the presence of Cu(acac)2, followed by sodium naphthalenide, afforded the aziridine 32 (67%), from which (-i-)-lycoricidine (33) can be easily obtained (Scheme 3.11). 

Abstract Asymmetric total synthesis of marine natural product, nakadomarin A, is described and as further extension, a novel synthesis of quinoline and indole ring system by ring closing metathesis is also described. 

Grasillas, A. Perez-Castells, J. Macrocyclization by ring-closing metathesis in the total synthesis of natural products Reaction conditions and limitations. Angew. Chem. Int. Ed. 2006,45, 6086-6101. 

These reactions involve metallate rearrangements , migratory insertion and transition metal-catalysed vinylic substitution reactions. They also perform well in applications in natural product synthesis . Many useful synthetic possibilities arise from application of ring-closing olefin metathesis (RCM) to unsaturated homoaldol products and their derivatives by means of the Grubbs catalyst 3942 4-286 Equation 105 presents some examples. ... 

Applications to natural product synthesis probe the limits of any synthetic method, as situations arise that would never have been considered in the course of first developing the method. Recent syntheses of valienamine 6, agelastatin 9 and tonantzitlolone 15 pressed the limits of ring-closing metathesis. 

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