Ferrier reaction/rearrangement

This methodology has been used for the synthesis of the C3-C14 segment 24 of the antitumor agent laulimalide 23 (Scheme 4.22) [35]. The constrained chiral BOX ligand 21c in combination with Cu(OTf)2 afforded dihydropyrane 6f by a cycloaddition reaction in good yield and ee this was converted to the C3-C14 segment 24 via a Ferrier-type rearrangement in several steps. 

Ferrier-type rearrangement to give glycal 74 [25] (Scheme 18). Spiroketals 75 are then obtained after desilylation. A similar sequence of reactions based on cyclic sulfate 76 furnishes adduct 77 which, after desilylation to give 78, provides spiroketals 79 upon N-iodosuccinimide (NIS) treatment. 

The Lewis acid-mediated allylic rearrangement of glycals like 28 to glycosides 29 known as the Ferrier-reaction is well known in carbohydrate chemistry [14-16]. It yields predominantly a-configurated hex-2-enopyranosides (cf. 29), either in the d-or L-sugar series. These may be hydrogenated to glycosides like the 2,3,6-trideoxy-species 30. 

The drawback of this method arises from the rearrangement of glycals, under the acidic conditions of the reaction, to the 2,3-unsaturated enoses (Ferrier reaction). The other problem is the incompatibility of some acid-labile protective groups with the relatively strong reaction conditions. These difficulties led to the development of different methodologies with the aim of minimizing the... 

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 so-called Ferrier (II) rearrangement is the most common approach to carbasugars, although it requires use of mercury and a reaction time (several hours). Pohl et al. [59], found that the Ferrier (II) rearrangement of 78 into 79 in the presence of palladium dichloride can be performed in less time and with higher yields by use of microwave irradiation rather than conventional heating (Scheme 12.37). 

Ferrier-type rearrangement,or Perrier reaction, but is called the Perrier reaction in this book to differentiate it from another type of rearrangement also developed by Perrier and co-workers. 

This reaction was initiaiiy reported by Perrier in 1979. It is a mercury (II) salt -induced or promoted conversion of 5-enopyranosides into cyclohexanones with stereochemical control, by which substituents at positions 3 and 5 are predominantly in a trans relationship. To differentiate from another reaction also discovered by Perrier (called the Perrier Reaction), this reaction is known as the Ferrier-II rearrangement, " Ferrier-II carbocyclization, Perrier carbocyclization, or Ferrier-II reaction. Occasionally, it is also referred to as the Perrier Reaction. Therefore, it is called the Ferrier-II rearrangement in this book. It is useful in the conversion of carbohydrates into carbosugars, myo-inositols, and other natural products. ... 

Only very recently [77], Sinay et al. presented a series of Ferrier-type rearrangements [78] of 5,6-unsaturated sugars to cyclohexenones. In this study, the same catalyst, applied to the reaction of furanyl C-glycoside 216, yielded exclusively, after reduction of the intermediate ketone, cyclohexanol 217 (Scheme 45). A conceivable Claisen rearrangement to a bicyclic product 218 was apparently not observed. 

---