Remote functionalization oxidation

This represents a particular case of the co-ozonolysis reaction when the intermediate carbonyl oxide can be trapped giving rise to other 1,2,4-trioxolanes having a remote functionality. Scheme 38 shows the ozonolysis of cyclohexene... 

Generally, hypervalent iodine reagents are often better than traditional reagents of similar reactivity, with respect to efficiency and chemoselectivity - sometimes even stereoselectivity. Unusual reactivity is another interesting feature which has often resulted in unexpected transformation. Examples of such reactions may be found in the oxidation of nitrogen-containing compounds, the Hofmann rearrangement in acidic conditions, the acetalization of carbonyl compounds in alkali, the remote functionalization of steroids, etc. Some unique transformations were effected in the... 

OXIDATIONS REMOTE FROM EXISTING SUBSTRATE FUNCTIONAL GROUPS... 

The focus will lai gely be on cases in which the functionalization or oxidation is performed with geometric control, and in which that control permits selective attack at various predetermined positions remote from any functional groups of the substrate. Those methods in which oxidations, using geometric direction, occur in the near neighborhood of substrate functional groups will also be discussed briefly. Such methods were an important source of inspiration for the more remote functionalization procedures, and they perform many useful transformations. 

The Barton reaction does not always afford only a single major product. J. Sejbal and co-workers isolated two products in a Barton reaction on triterpene substrates. In this example, reaction at either (or both) the C4 and C10 methyl groups was expected, but oxidation of the C8 methyl group was not. This remote functionalization occured via... 

Some aspects of the chemistry of lauren-l-ene, including the remote functionalization of other rings based on the I2-Pb(OAc)4 oxidation of laurenan-2-ols, have been described.158 X-Ray crystallographic evidence has been presented for the structure (92) of cinncassiol D, a pentacyclic diterpenoid from the dried bark of Cinnamomum cassia possessing anti-complement activity.159... 

A patent has been lodged covering the sulfochlorination of gaseous alkanes. " Photochemical bromination using N-bromosuccinimide of the arenes (136) has been examined under a nitrogen atmosphere. The remote functionalization of the alcohol (137) has been carried out using DIB/Ii/cyclohexane. The product obtained from this, after oxidation, is the iodoketone (138, 84%). ... 

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