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Horner-Wadsworth-Emmons reaction natural product synthesis

Recent advances in the stereoselective olefination of phosphorus-stabilized carbon nucleophiles have been reviewed. Recent applications of the Horner-Wadsworth-Emmons reaction to the synthesis of natural products have been highlighted. ... [Pg.365]

Recent advances in the stereoselective olefination of phosphorus-stabilized carbon nucleophiles have been reviewed. Applications of the Horner-Wadsworth-Emmons reaction to the synthesis of natural products have been highligted. A highly Z-selective synthesis of a, -unsaturated nitriles using the Homer-Wadsworth-Emmons reaction has been reported this involves a new nitrile reagent, (o-t-BuC6H40)2P(0)CH2CN, which reacts with various types of aldehydes with 86 to >99% Z selectivity. [Pg.386]

Other examples of Ugi reactions combined with RCM have been described in the literature. Hebach and Kazmaier reported the synthesis of conformationally fixed cyclic peptides [70] and Beck and Domling synthesized biaryl-containing natural product-like macrocycles using this method [41]. The same group also reported combination of Passerini and Horner-Wadsworth-Emmons reactions to obtain butenolides [67] and another variation for the combinatorial synthesis of thiazoles [69]. [Pg.155]

All the carbons of the target were introduced by a Horner-Wadsworth-Emmons reaction of ent-427 with a-ethylacrolein, which gave a mixture of ( ) and (Z) olefins 437. The synthesis of the E) isomer of 437 constitutes a formal synthesis of coronafacic acid because its conversion to the natural product has been reported by Nara, Toshima, and Ichihara [90]. They reported that 437-E could be cyclized with base to hydrindenones 438 and 439 in 71 % yield. After purification, the major diastereomer 438 could be hydrolyzed to coronafacic acid in 95 % yield. [Pg.348]

Within the context of total synthesis, the application of CM to a one-pot sequential protocol has the potential to dramatically simplify the preparation of complex natural products. Trost and co-workers recently demonstrated an elegant example of this, wherein a one-pot CM-Takai olefination reaction was used for the preparation of the antitumor agent callipeltoside A and various analogs (Scheme 21). By using a three-step, two-pot sequence employing this protocol, the synthetic route toward these compounds was shortened by five steps and olefin stereoselectivity was increased (4 1 to >8 1 E/Z) relative to previous syntheses employing a classical Emmons-Wadsworth-Horner approach. [Pg.198]


See other pages where Horner-Wadsworth-Emmons reaction natural product synthesis is mentioned: [Pg.486]    [Pg.197]    [Pg.214]    [Pg.14]    [Pg.43]   
See also in sourсe #XX -- [ Pg.429 , Pg.430 , Pg.431 , Pg.432 , Pg.433 , Pg.434 , Pg.435 , Pg.436 , Pg.437 , Pg.438 , Pg.439 , Pg.440 , Pg.441 , Pg.442 ]




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Emmons

HORNER WADSWORTH - EMMONS

Horner reaction

Horner synthesis

Horner-Emmons reaction

Natural products, synthesis

Nature, reactions

Reactions natural products

Wadsworth-Emmons

Wadsworth-Emmons reaction

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