Imino -Wittig rearrangements

The discoveiy that a mixture of (Z)-(94a) and (Z)-(94b), on treatment with LDA, forms only (Z)-(95a) and (Z)-(95b) is consistent with an intramolecular mechanism (e.g. Scheme 6) for this new imino-Wittig rearrangement of hydroximates alternative radical pathways have also been discussed for reactions of Z- and. E-isomers.169... 

As an application of this class of rearrangement, Naito s group reported a synthesis of cytoxazone (50) from 49 based on the imino [1,2]-Wittig rearrangement (equation 27). ... 

A diastereoselective imino [1,2]-Wittig rearrangement of allyl hydroximates provides for the preparation of optically active a-hydroxy oxime ethers when R3 is designed (g) as shown to participate in the reaction (Scheme 5).8... 

The imino [1,2]-Wittig rearrangement was originally reported by Katritzky in 1981, and has been subsequently explored by Uneyama and Naito These transformations involve rearrangements of benzyl or allyl hydroximates to a-hydroxy oximes. An illustrative example involves the... 

The imino [1,2]-Wittig rearrangement of hydroximates has also been employed in the construction of natural products. For example, ( )-cytoxazone (88) was prepared fi om intermediate 87, which was generated via [1,2]-Wittig rearrangement of 86. An asymmetric synthesis of (+)-... 

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