title: P,C-Chelation versus P,P-coordination of unsymmetrical phosphorus ylides in palladacyclopropa[60]fullerene complexes; synthetic, spectroscopic, and theoretical studies.
abstract: The new palladacyclopropa[60]fullerene complexes incorporating α-keto stabilized phosphorus ylides were synthesized in a three-component reaction of the unsymmetrical phosphorus ylides [Ph2P(CH2)nPPh2[double bond, length as m-dash]C(H)C(O)C6H4-m-R] (n = 1, R = Br, NO2, (Y(1), Y(2)); n = 2, R = Br, NO2, (Y(3), Y(4))), C60 and Pd(dba)2 (dba = dibenzylideneacetone). The obtained novel P,C-chelated [(η(2)-C60)Pd(κ(2)-Y(1))] (1) and [(η(2)-C60)Pd(κ(2)-Y(2))] (2) complexes and P,P-coordinated [(η(2)-C60)Pd(Y(3))2] (3) and [(η(2)-C60)Pd(Y(4))2] (4) complexes were characterized successfully by IR, UV-Vis, ESI-MS and NMR ((1)H, (13)C and (31)P) spectroscopic methods. Complexes 1-4 are rare examples of palladacyclopropa[60]fullerene complexes with phosphorus ylide ligands. Spectroscopic results revealed that none of possible side products including P,P-coordinated [(η(2)-C60)Pd(Y(1))2] and [(η(2)-C60)Pd(Y(2))2] complexes and also P,C-chelated [(η(2)-C60)Pd(κ(2)-Y(3))] and [(η(2)-C60)Pd(κ(2)-Y(4))] complexes are formed. The EDA analysis indicated that in all the above complexes the metal-ligand bonds are mostly electrostatic in nature.
authors.affiliation: Faculty of Chemistry, Bu-Ali Sina University, Hamedan, 65174, Iran. jsabounchei@yahoo.co.uk.
authors.forename: Seyyed Javad
authors.initials: SJ
authors.lastname: Sabounchei
authors.forename: Marjan
authors.initials: M
authors.lastname: Hosseinzadeh
authors.forename: Ali
authors.initials: A
authors.lastname: Hashemi
authors.forename: Sadegh
authors.initials: S
authors.lastname: Salehzadeh
authors.forename: Farahnaz
authors.initials: F
authors.lastname: Maleki