New synthetic route to polyphosphine ligands bearing 1,2,4,5-tetrakis(phosphino)benzene framework: Structural characterizations of 1,4-(PPh2)2-2,5-(PR)2)2 -C6 F2 (R = Ph, i Pr, Et)
Document Type
Article
Publication Date
10-15-2004
Department
Department of Chemistry
Abstract
Reactions of 1,4-dibromo-2,5-difluorobenzene with two equivalents of lithium diisopropylamide at low temperature (T < -90 °C) followed by a quench with a slight excess of ClPPh 2 afford 1,4-dibromo-2,5-bis(diphenylphosphino)-3,6-difluorobenzene (1) in good yields. Reacting 1 with two equivalents of BuLi followed by a quench with a slight excess of ClPR 2 yield novel 1,2,4,5-tetrakis(phosphino)-3,6-difluorobenzenes 1,4-(PPh2) 2-2,5-(PR2)2-C6F2 (R = Ph (2a); R = iPr (2b); R = Et (2c)) in moderate yields. Compounds 1 and 2a-c were characterized by multinuclear NMR spectroscopy and elemental analyses. In addition, molecular structures of 2a-c have been determined by single crystal X-ray crystallography. Phosphorus atoms of PPh2/PR2substituents in 2a-c are displaced from the plane of the central phenyl ring due to steric interactions with neighboring groups.
Publication Title
Journal of Organometallic Chemistry
Recommended Citation
Kongprakaiwoot, N.,
Luck, R.,
&
Urnezius, E.
(2004).
New synthetic route to polyphosphine ligands bearing 1,2,4,5-tetrakis(phosphino)benzene framework: Structural characterizations of 1,4-(PPh2)2-2,5-(PR)2)2 -C6 F2 (R = Ph, i Pr, Et).
Journal of Organometallic Chemistry,
689(21), 3350-3356.
http://doi.org/10.1016/j.jorganchem.2004.07.042
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/6786