Date of Award
Doctor of Philosophy
Richard C. Larock
Additions of organometallic reagents to vinylic epoxides have become useful synthetic reactions for preparing allylic alcohols when the regio- and stereochemistry of the product can be controlled. Analogous organometallic processes employing vinylic oxetanes have never been reported in the literature. The results presented in this dissertation are the first observed examples of vinylic oxetanes reacting with organometallic reagents to afford homoallylic alcohols. The scope and limitations of these reactions will be discussed;The reactions of aryl- and vinylpalladium compounds with vinylic oxetanes provide a high yielding route to functionally substituted homoallylic alcohols. The homoallylic alcohols are isolated as mixtures of E- and Z-isomers. The E/Z ratio, however, is generally greater than 80:20. Catalytic amounts of palladium can be employed in the reaction if cupric chloride and oxygen are used to reoxidize the palladium;Vinylic oxetanes have also been observed to react with various nucleophiles in the presence of a catalytic amount of palladium(0) to produce the corresponding di- or trisubstituted homoallylic alcohols. These reactions proceed in high yield and are both regio- and stereoselective. It has also been shown that trisubstituted allylic alcohols can be produced in high yields, via palladium(0)-catalyzed nucleophilic ring-opening of substituted vinylic epoxides. Conditions have been found for this reaction where either the E- or Z-isomer of the trisubstituted allylic alcohol can be formed preferentially;The reactions of vinylic oxetanes with organolithium, -copper and -boron reagents have been explored. The corresponding homoallylic alcohols are isolated as mixtures of stereoisomers in good yields.
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/
Sandra K. Stolz-Dunn
Stolz-Dunn, Sandra K., "Synthesis of allylic and homoallylic alcohols via organometallic ring-opening of vinylic epoxides and oxetanes " (1989). Retrospective Theses and Dissertations. 9087.