Chlorosulfites prepared in situ using thionyl chloride react with nitrile complexes of titanium (IV) fluoride to give a one-pot conversion of alcohols into amides. For the first time, amides are obtained from cyclic alcohols with stereoretention. Critical to the design of these new Ti(IV) reactions has been the use of little explored Ti(IV) nitrile complexes which are thought to chelate chlorosulfites in the transition state to create a carbocation that is rapidly captured by the nitrile nucleophile via a front-side attack mechanism.
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| http://dx.doi.org/10.1002/ejoc.201101165 | DOI Listing |
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