The IPB has once again been recognized for its exemplary actions in terms of equal opportunity-oriented personnel and organizational policies and has received the TOTAL E-QUALITY certification for the…
The Plant Science Student Conference (PSSC) has been organised by students from the two Leibniz institutes, IPK and IPB, every year for the last 20 years. In this interview, Christina Wäsch (IPK) and…
Jimenez-Aleman, G. H.; Schöner, T.; Montero-Alejo, A. L.; Brandt, W.; Boland, W.;Improved synthesis of the chrysomelid pheromone (6R,7S)-(+)-himachala-9,11-diene via spontaneous bromination and didehydrobromination of 2,6,6,9-tetramethyl-bicyclo[5.4.0]undec-8-eneARKIVOC2012371-378(2012)DOI: 10.3998/ark.5550190.0013.326
A convenient synthesis of (6R,7S)-(+)-himachala-9,11-diene, the pheromone of the chrysomelid beetle Phyllotreta striolata is described. The diene is obtained in a single operation by a spontaneous “bromination/dehydrobromination” of 2,6,6,9-tetramethylbicyclo[5.4.0]undec-8-ene. The halogenation/dehalogenation sequence proceeds spontaneously in CCl4, and is less uniform in CH2Cl2 and CHCl3. 1H NMR experiments carried out in presence of the radical scavenger di-tert-butyl-4-methylphenol suggest an ionic mechanism for this reaction. Theoretical calculations demonstrate that the spontaneous reaction profits from the strongly exergonic addition of Br2 to the double bond and an almost neutral energy difference between the starting olefin and the diene pheromone.