Amidoxime, conversion from

The conversion of the polystyrene-supported selenyl bromide 289 into the corresponding acid 290 allowed dicyclohexylcarbodiimide (DCC)-mediated coupling with an amidoxime to give the 1,2,4-oxadiazolyl-substituted selenium resin 291 (Scheme 48). Reaction with lithium diisopropylamide (LDA) and allylation gave the a-sub-stituted selenium resin 292, which was then used as an alkene substrate for 1,3-dipolar cycloaddition with nitrile oxides. Cleavage of heterocycles 293 from the resin was executed in an elegant manner via selenoxide syn-elimination from the resin <2005JC0726>. 

A general method for the synthesis of pyrimidine A-oxides from amidoximes is described. The conversion involves treatment of various carboxamide oximes 325 with 1,1,3,3-tetramethoxypropane, 2,4-pentanedione or 3-ethoxy-2-methylpropenal in the presence of CF3COOH to afford pyrimidine 1-oxides 326 (equation 141) . 

Hydroxyimino-3-aminoproply (inulin can be synthesized from tMcyanoelhyl (inulin (19) by reaction with hydroxylamine in a neutral medium (Figure 5.7), giving about 80% conversion (Verraest, 1997). The amidoximes can be found in two forms (22, 23), the iyn-hydroxyimino being the most stable. Amidoximes are particularly reactive compounds and will effectively chelate transition cations such as Cu2+ (24). 

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