Izlaganje sa skupa

The Structure of Polyfulvenes

M. Neuenschwander ; Institut fur Organische Chemie der Universitat Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
P. Kronig ; Institut fur Organische Chemie der Universitat Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
S. Schonholzer ; Institut fur Organische Chemie der Universitat Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
M. Slongo ; Institut fur Organische Chemie der Universitat Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
B. Uebersax ; Institut fur Organische Chemie der Universitat Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
C. Rentsch ; Institut fur Organische Chemie der Universitat Bern, Freiestrasse 3, CH-3012 Bern, Switzerland

Sažetak

Cationic polymerisation of 6,6-disubstituted pentafulvenes
yields highly unsaturated, reactive macromolecules of high mo- .
lecular weight. The mechanistic pathways leading to the polymers
are discussed, and the structure XIV of the polymers has been
elucidated by a combination of spectroscopic methods as well as by
comparison with model compounds. In contrast to reports in the
literature, the main process in thermal oligomerisation of simple
pentafulvenes at 20 °c is a Diels-Alder reaction giving products of
type XXI. Anionic polymerisation of pentafulvenes is initiated by
traces of sodium cyclopentadienide or phenylsodium respectively.
The reaction products consist of a mixture of oligomers of the
series (fulvene)n. This surprising result can be explained by structure
elucidation of the fulvene dimers, which gives formula XX.
The mechanistic aspects of the reaction are discussed.

Ključne riječi

Hrčak ID:

194481

URI

https://hrcak.srce.hr/194481

Datum izdavanja:

25.1.1981.

Posjeta: 681 *