Functional group transformations allyl rearrangement

Allylic rearrangement Functional group transformation in which double-bond migration has converted one allylic structural unit to another, as in ... 

A general discussion of such inherent problems and the principles of allylic rearrangements will be presented first, followed by specific examples of functional group transformations, which will be systematically surveyed regardless of the mechanism involved. 

A versatile and very powerful strategy for functional group transformation via allyl rearrangement involves intramolecular reactions of the 2,3- and 3,3-sigmatropic type, as exemplified in generalized form in Scheme 8. 

Under the same conditions, several types of hydrocarbon are also converted to fully deuterated compounds. The results are summarized in Table 1. Cydooctene was also transformed into fully deuterated cydooctene without a skeletal rearrangement. As shown in entries 2 and 3, saturated hydrocarbons have also been transformed into fully deuterated compounds. As described above, an interaction between allylic C-H bonds and palladium hydride induces the H-D exchange reaction for alkenes. H-D exchange in alkanes, however, cannot be explained in this way. Direct C-H activation without assistance from any functional group may be a route to the formation of fully deuterated alkanes. 

Uracil-type compounds are insoluble in common organic solvents. Radicals R4 in 168 have been used to permit a more facile allylation or rearrangement to 167, as shown in Scheme 37). Further transformation into the amide functional group permits preparation of 169, and finally 170 (93ACS72). 

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