Synthesis, structure, and reactivity of fluorous phosphorus/carbon/phosphorus pincer complexes derived from P(CH2)5P backbones Academic Article uri icon

abstract

  • Reactions of the diphosphine H2P(CH2)5PH2 and fluorous alkenes H2C{double bond, long}CHRfn (excess; Rfn = (CF2)n-1CF3; n = a, 6; b, 8; c, 10) at 60 °C in the presence of AIBN give the precursors (RfnCH2CH2)2P(CH2)5P(CH2CH2Rfn)2 (2a-c; 68-74%). These react with Pd(O2CCF3)2 in CF3C6F5 at 80 °C to give the title complexes {A figure is presented} (5a-c, 51-18%). Addition of LiCl to 5b gives {A figure is presented} (6b, 97%); subsequent reaction with MeLi affords the corresponding methyl complex (97%). A solvate of 6b is crystallographically characterized. The structure exhibits CH2CH2Rf8 groups with nearly anti C-C-C-C conformations, extending in parallel above and below the palladium square plane to create fluorous lattice domains. Reactions of 2b and other metal complexes are described; in the cases of (PhCN)2PdCl2 or (COD)2PtCl2 (CF3C6H5, room temperature), bimetallic species in which two MCl2 moieties are bridged by two diphosphines appear to form. The CF3C6F11/toluene partition coefficients of 2a-c and 5a-c establish high fluorophilicities; despite the lower fluorine weight%, those of 5a-c are slightly greater ((97.4-99.7):(2.6-0.3) versus (95.3-99.3):(4.7-0.7)). © 2006 Elsevier B.V. All rights reserved.

author list (cited authors)

  • Consorti, C. S., Hampel, F., & Gladysz, J. A.

citation count

  • 21

publication date

  • December 2006