Ferrier-I rearrangement

One of the most convenient methods for the synthesis of 2,3-unsaturated sugars is the so-called Ferrier-I rearrangement of glycals (O Scheme 6). This reaction allows one to obtain the unsaturated targets via the process in which the double bond migrates from the C1-C2 to the C2-C3 position [1,2,4,5,11],... 

The Ferrier-I rearrangement represents now a classical methodology which should be considered in planning the syntheses of optically pure targets from sugar chirons. Such a conclusion may be illustrated by the preparation of p)ranosyl nucleosides obtained by this procedure. 

The most important of such processes is the reaction of glycals with alcohols catalyzed with Lewis acids known as Ferrier-I rearrangement [1,2] an example is shown in Figure 10.1. Reaction of glycals with allylsilanes catalyzed by Lewis acids is also a convenient method for the synthesis of C-allyl glycosides (e.g., 3) [2,3],... 

Aza- and 1-thia-Ferrier-I rearrangements allow to obtain the corresponding nitrogen and sulfur derivatives. This process was used for the preparation of many biologically important molecules, such as 2,3-unsaturated pyranosyl nucleosides 4 or phosphorylated pyranosyl nucleoside 5 (Figure 10.2) [4],... 

Kanomata, K. Toda, Y. Shibata, Y. Yamanaka, M. Tsuzuki, S. Gridnev, I. D. Terada, M. Secondary Stereocontrolling Interactions in Chiral Bronsted Acid Catalysis Study of a Petasis-Ferrier-Type Rearrangement Catalyzed by Chiral Phosphoric Acids. Chem. Sci. 2014,5,3515-3523. 

The same catalyst has been used by this research group in synthesis of j -amino-aldehydes (146) by combining two catalytic reactions, i.e. a Ni(II) complex-catalyzed isomerization of a double bond and a chiral phosphoric acid (127)-catalyzed aza-Petasis-Ferrier rearrangement in a highly dia-stereo- and enantioselective manner (Scheme 39). ... 

Mild reaction conditions using catalytic triflates of rare earth metals were also developed. This was based on the better Lewis acid properties of the catalysts, their ready availability and easy handling. An alternative is the use iron(iii) triflate. In carbohydrate chemistry, iron(iii) triflate has only been used for oxidative C-C bond cleavage, thioglycosylation of peracetylated glycosides and type I Ferrier rearrangement of glucal. ... 

In 2001 and 2002, the Smith group first disclosed the total synthesis of (+)-zampanolide [164] and (-n)-dactylolide [165], respectively. The synthetic strategy of (-i-)-zampanolide relied on the stereoselective construction of the 2,6-cjT-tetrahydropyran unit via the Petasis-Ferrier rearrangement and Horner-Wadsworth-Emmons macrocyclization at the C(2)-C(3) junction (Scheme 2.47). 

The aza-Petasis-Ferrier rearrangement is not a true concerted sigmatropic reaction, since it is thought to proceed via C-O bond cleavage of a hemiaminal vinyl ether by the action of an acid catalyst to afford a reactive uninium cation and the enol form of an aldehyde these two intermediates combine subsequently in a Mannich-type process, leading to [i-amino aldehydes (Scheme 40.45) (54). Recently, Terada and Toda used a BlNOL-derived phosphoric acid diester as a catalyst for this interesting reaction [55]. 

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