Bicyclic heteroatom systems. Part 1: Synthesis of bicyclic germanes. Part 2: Synthesis of cyclic and bicyclic phosphonates

Anthony Gerard Sommese, Marquette University


This study focused on the synthesis of bicyclic systems containing a heteroatom (either Ge or P). Part one contains the synthesis, characterization, and equilibration studies of 3-germabicyclo (3.2.1) octane (3GBO) and 2-germabicyclo (2.2.1) heptane (2GBH) derivatives. The former was synthesized in a seven-step sequence culminating in the reaction of a bis-Grignard reagent derived from cis-1,3-bis-(bromomethyl)cyclopentane and R$\sb{2}$GeCl$\sb{2}$ (R = Ph or Me). The latter synthesis required a five-step sequence culminating with a platinum catalyzed intramolecular hydrogermylation reaction of di-n butyl(3-cyclopentenylmethyl)germane. Derivatives of 3GBO were initially formed by a cleavage reaction of one/both phenyl group(s) in 3,3-diphenyl-3GBO, by molecular bromine. Additional derivatives were formed by nucleophilic attack on the bromo derivatives. Fluoride ion catalyzed isomerization reactions of exo-3 methyl-3-phenyl-3GBO were unsuccessful; either a hypervalent fluoro substituted germane was not formed under the reaction conditions, or if formed did not undergo intramolecular ligand rearrangement at an observable rate. New compounds were characterized by $\sp{1}$H and $\sp{13}$C NMR, IR and mass (70 ev and high resolution) spectrometry. Combustion analysis was also employed. Part two described different synthetic approaches to 1-phospha-2,10-dioxabicyclo (4.4.0) decane-1-oxide, which can be viewed as a double phostone. The known methods of simple six-membered ring phostone formation are reviewed. Modification of the existing thermal method as well as a new more gentle approach are presented. This new approach will henceforth be known as "phosphonolactonization". This method relied on the base catalyzed closure of diethyl 4-hydroxybutylphosphonate to afford the simple six-membered ring phostone in 60-70% yield. Phosphonolactonization was then applied to diethyl 4-(1,7-dihydroxyheptyl)phosphonate to form the desired compound in 40-60% yield. Three different routes to the diol precusor are described. The desired molecule has the possibility of existing in either the cis or trans form. The methodology employed gave only the cis isomer. An alternative route that relied on the formation of two carbon-carbon bonds in the last reaction step is described. This methodology also afforded only one isomer, which we believe to be cis. Chemical transformations of the cis isomer to give the trans isomer were explored. New compounds were characterized by $\sp{1}$H, $\sp{13}$C and $\sp{13}$P NMR spectroscopy, also IR spectroscopy and elemental combustion analysis.

Recommended Citation

Sommese, Anthony Gerard, "Bicyclic heteroatom systems. Part 1: Synthesis of bicyclic germanes. Part 2: Synthesis of cyclic and bicyclic phosphonates" (1989). Dissertations (1962 - 2010) Access via Proquest Digital Dissertations. AAI9014064.