Synthesis of cyclopropene derivatives and chemistry of fullerenes
Author
Gesenberg, Christoph
Date
1997Degree
Doctor of Philosophy
Abstract
New synthetic routes leading to 1-vinylcyclopropene and methylenecyclopropene were established making use of the Vacuum Gas-Solid Reaction (VGSR) technique. Both syntheses were planned in a way that allowed the use of solid fluoride as the dehalosilylation inducing reagent in the last step. The decomposition of methylenecyclopropene at temperatures above $-$75$\sp\circ$C was investigated and a dimer of methylenecyclopropene was proposed as the initial decomposition product.
Fullerenes have been synthesized and separated using chromatographic techniques. Helium containing isomers of higher fullerenes were analyzed by $\sp3$He NMR spectroscopy and signals were assigned to isomers of C$\sb{76}$, C$\sb{78}$ and C$\sb{84}$. A novel C$\sb{60}$ derivative has been synthesized by the reaction of C$\sb{60}$ with cyclopropa (b) naphthalene and the product of the reaction with $\sp3$He@C$\sb{60}$ revealed the signal of the new compound in the $\sp3$He NMR. Fullerene hydrides $\sp3$He@C$\sb{60}$H$\sb{36}$ and $\sp3$He@C$\sb{60}$H$\sb{18}$ were synthesized by Birch reduction or reaction of $\sp3$He@C$\sb{60}$ with dihydroanthracene and the products were analyzed by $\sp3$He NMR. The spectra revealed one isomer for C$\sb{60}$H$\sb{18}$ and two isomers for C$\sb{60}$H$\sb{36}$. The most intense signal for C$\sb{60}$H$\sb{36}$ was assigned to the isomer with D$\sb{\rm 3d\sp\prime}$ symmetry based on the $\sp3$He NMR chemical shift value.
Keyword
Organic chemistry