Diphosphine Compounds, Part III: UV/Visible Spectroscopy and Novel Routes to Functionalized Diphosphine-M(CO)₆ Complexes (M = W, Mo, or Cr)

Abstract

Reaction of coordinated (diphenylphosphino)methane and ketones or aldehydes have been characterized by ³¹P{H¹}-NMR, ¹H{³¹P}-NMR, and UV/vis spectroscopy in dichloromethane. Group VI metals hexacarbonyl [M(CO)₆ where M = Cr, Mo, and W] reacted with (diphenylphosphino)methane, [(Ph₂P)₂CH₂], to give [(OC)₄M{(Ph₂P)₂CH₂}] depending upon the reaction conditions. Condensation of [(CO)₄M{(Ph₂P)₂CH₂}] with different ketones or aldehydes forms [(CO)₄M{(Ph₂P)₂C = CR₁R₂}]. Complexes of the types [(OC)₄M{(Ph₂P)₂C = CR₁R₂}] reacted with hydrazine in a Michael addition to give [(CO)₄M{(Ph₂P)₂CHC(R₁R₂)NHNH₂}](1.3a–e), which condensed with different ketones and aldehydes to give complex of the type [(CO)₄M{(Ph₂P)₂CHC(R₁R₂)NHN = C(R₃)] (1.4a–e). The structures of the complexes are discussed on the basis of elemental analysis (EA), IR,¹H-NMR, ³¹P-NMR spectroscopic data, and FAB mass spectra. The UV/vis spectra show two absorption bands with the low energy band moving to lower energy with increasing substitution on the (diphenylphosphino) methane (dppm) (a bathochromic effect).

Keywords:

• Diphosphine compounds
• organometallic
• transitions metal complexes
• UV/visible spectroscopy