Trichloroisocyanuric acid secondary alcohols

Apart from sodium hypochlorite, a number of alternative secondary oxidants for TEMPO-mediated alcohol oxidations can be employed. These include cerium (IV) ammonium nitrate (CAN),24 trichloroisocyanuric acid (TCCA),25 oxone ,26 MCPBA,2,3,7 PhI(OAc)2,27 W-chlorosuccinimide,28 sodium bromite,29 electrooxidation,8,21 H5IO626 and a polymer-attached diacetoxybromide (I) complex.30... 

Other reagents, providing a source of electrophilic halogen, able to selectively oxidize secondary alcohols include molecular chlorine,13 molecular bromine,13c 3-iodopyridine dichloride,13a trichloroisocyanuric acid (TCIA),14 the complex HOF MeCN15 and tetraethylammonium trichloride.16... 

As mentioned before a PEG-supported TEMPO proved to be very efficient in the oxidation of 1-octanol to octanal not only with sodium hypochlorite, but also in combination with different terminal oxidants such as bis(acetoxy)iodobenzene and trichloroisocyanuric acid. This reaction could be extended to acyclic and cyclic primary and secondary alcohols with excellent results. It is remarkable that the PEG-supported TEMPO maintained the good selectivity for primary vs secondary ben-zylic alcohol oxidation typical of non-supported TEMPO. 

Oxidation of alcohols is often aeeomplished conveniently by or via hypochlorites in sueh Ireatment of primary-seeondary diols, a selectivity of 1 7-20 is reached for the seeondary hydroxyl group. In general, sodium hypochlorite in acetic acid solution is used for this purpose (25). We obtained very good results, based on chlorine or trichloroisocyanuric acid (TCIA) in methanol in acid-buffered medium. The hy-droxyketone [7] can be formed reliably with a selectivity of 1 50-65. The improved selectivity is based on the use of the lowest convenient temperature and on the Promotion of the exchange of positive chlorine between primary and secondary alcohol positions (including from relatively stable methyl hypochlorite). 

Hiegel, GA., and M. Nalbandy, The Oxidation of Secondary Alcohols to Ketones with Trichloroisocyanuric Acid, Synth. Commun. 22 1589-1595 (1992). 

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