186185-77-3Relevant articles and documents
Preparation and properties of 9-methylenetricyclo[4.3.0.03,8]non-4-ene
Gleiter, Rolf,Herb, Thilo,Lange, Holger
, p. 9236 - 9241 (1996)
Several attempts to synthesize 9-methylenetricyclo[4.3.0.03,8]non-4-ene (2) are described, first by enlargement of the tricyclo[3.3.0.03,7]octane skeleton and second by reduction of the alcohol function in 9-methylenetricyclo[4.3.0.03,8]non-4-en-2-ol (18) and its derivative 5-methylene-11-phenyl-10, 12-dioxatetracyclo[7.3.0.02,6.04,8]dodecan-3-ol (19). Both routes proved to be unsuccessful. The synthesis of 2 could be achieved by ring opening of 7-methyl-3,8-dioxapentacyclo[4.4.1.02,4.05,9.0 7,10]-undecane (26) with Li in EDA to yield 9-methyltricyclo[4.3.0.03,8]nonane-4,9-diol (27). By using the Swern reagent, 27 could be transformed in a one-pot reaction to 9-methylenetricylo[4.3.0.03,8]-nonan-4-one (31), which yielded 2 via a Shapiro reaction. The PE spectra of 2 and 18 reveal an energy splitting of the π bands by about 1 eV. This splitting has been analyzed with the aid of HF-SCF calculations. A considerable interaction between the central six-membered ring and the double bonds in 2 and 18 has been found.
