Oxygen-nitrogen derivatives alcohols

Alkyl halides undergo nucleophilic substitution reactions by unimolecular (S l) and bimolecular (S 2) pathways. The substitution reactions of alkyl halides, and of derivatives of alcohols, utilize oxygen, nitrogen, sulfur and carbon nucleophiles. 

A procedure for oxygen-nitrogen transposition with allylic rearrangement involves treating an allylic alcohol with trichloroacetonitrile, then heating the derived trichloroacetimidate. Rationalize this transformation. 

Vinylogous amides, which have an enamine function in conjugation with a carbonyl group, constitute tridentate systems and thus open the possibility of alkylation on carbon, nitrogen, or oxygen. It has been found that the pyrrolidine enamine of acetylacetone gives rise to a carbon mcthylation but an oxygen ethylation product 41). The alkylation of cyclic 1,3-diketone-derived enamines has been studied 41,283). O Alkylation was found in alcohol solvents and predominant C alkylation in nonprotonic solvents. 

Although transition metal-catalyzed allylic alkylation has become one of the most powerful methods in chemical synthesis, the formation of ether bonds using this process has been slow to evolve.119-121 The main reasons for this disparity are the lower nucleophilicity and higher basicity of oxygen nucleophiles, particularly those derived from aliphatic alcohols, compared to their carbon or nitrogen analogs. However, this notion has rapidly been revised, as recent advances in the O-allylation area have largely addressed the issue of the reactivity mismatch between the hard alkoxide and the soft 7r-allylmetal species to provide a considerable body of literature. 

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