Leonie Braun, G. Kehr, T. Blömker
Jul 1, 2007
Citations
0
Influential Citations
8
Citations
Journal
European Journal of Inorganic Chemistry
Abstract
Deprotonation of the readily available chelate phosphane bis(diphenylphosphanyl)acetonitrile (6) leads to stabilized carbanion system 7. Lithiobis(diphenylphosphanyl)acetonitrile (7) features a unique thf-stabilized monomeric structure in the crystal form with a short cyanonitrogen–Li contact. Alkylation of 7 with n-alkyl bromides (R–Br, R = ethyl, n-propyl, n-butyl, n-hexyl) takes place selectively at one phosphorus atom to yield stabilized ylides 8a–d (two examples characterized by X-ray diffraction). Treatment of 7 with the more reactive alkylation agents methyl iodide or benzyl bromide results in alkylation at both phosphorus atoms to give delocalized bis(phosphonium)ylides 9a,b (both characterized by X-ray diffraction). Similarly, the reaction of 7 with 1,3-dibromopropane or 1,4-dibromobutane yields six- and seven-membered heterocyclic bis(phosphonium)ylides 10a,b, respectively. The spectroscopic characterization and X-ray crystal structure analysis again indicate the presence of delocalized Ph2RP–C(CN)–PRPh2 substructures. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)