Reaction of Ylides with Carbodiimides

The reaction of ylides with carbodiimides usually produces linear 1 1 adducts. The adducts derived from DMSO and carbodiimides undergo a facile reaction with primary alcohols to give an aldehyde (Moffat oxidation). With phenols and carboxyhc acids, alkylation products and esters, respectively, are formed. The oxidation proceeds under mild conditions and can be applied to sensitive compounds. Primary alcohols are oxidized solely to aldehydes without the formation of even trace amounts of carboxylic acids. The carbodiimide adducts generated from DMSO or the dimethylseleniumoxide adducts have structure 369 (X = S, Se). 

The subsequent reaction of the adduct 369 with an alcohol gives rise to the formation of the aldehyde 370.  

In the reaction of phenol derivatives 371 with DMSO in the presence of DCC, 0- and p-methylthiomethyl derivatives 372 are formed.  

Starting with an optically active sulfoxide 374 the DCC reaction gives the optically active derivative 375 (5-29 % optical purity).  

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