Synthesis of Cyclopentadienyl Derivatives: Stereoelectronic Effects in the Diels-Alder Cyclocondensation Reaction.

This dissertation is divided into three chapters. Chapter one describes attempts to synthesize bis-monosubstituted cyclopentadienyl compounds as probes for complexation to transition metals. Prior to the attempted synthesis of bis-monosubstituted cyclopentadienyl compounds, the syntheses of two different organic frameworks bearing a C$\sb2$-symmetry axis is described; namely, the 1,3-dioxolane-2,2-dimethyl and the 1,1$\sp\prime$-binaphthyl frameworks. Chapter two describes the attempts to synthesize monofulvene derivatives as model compounds for the synthesis of difulvenes. Also, chapter two describes the attempts to synthesize different difulvene derivatives, that for the most part bear a C$\sb2$-symmetry axis, as model compounds for cyclopentadienyl-derivative anions to be completed to transition metals. The syntheses of several different frameworks bearing C$\sb2$-symmetry axis, such as 1,5-disubstituted-trans-decalin, 2,7-disubstituted-tricyclo (5.3.3.0$\sp{6,10}$), 1,3-dioxolane-2,2-dimethyl and 2,2$\sp\prime$disubstituted-1,1-binaphthyl, are presented. Chapter three describes attempts to synthesize tricyclo (9.3.0.0$\sp{4,8}$) tetradeca-4,7,11,14-tetraene via two different routes as suggested by retrosynthetic analysis; namely, via a thermal rearrangement of a bis-spirocyclopentadiene derivative and via Diels-Alder cyclocondensation of an electron deficient diene with cyclooctadiene. The Diels-Alder cyclocondensation reaction used in the first step of one of these synthetic methods is examined in order to find out the origin of the dienophile $\pi$-stereoselectively, by a combination of structural techniques and reactant modifications