Synthesis and Structure of η4-Enone Complexes of Ruthenium(0)

Article abstract of DOI:10.1002/hlca.19930760220

A variety of 4-enone)> complexes (L = phosphines, phosphites, and arsines, enone = (E)-4-phenylbut-3-en-2-one) have been synthesized. 1H, 13C-, and 31P-NMR spectra are reported and the X-ray structures of two Ru complexes with L = Ph3P (7), Et3P (10) and one Fe complex with L = Ph3P (14) are presented.All three compounds crystallize in the same monoclinic space group P2₁/n with a = 10.575(2) Angstroem, b = 9.213(2) Angstroem, and c = 27,608(5) Angstroem, β = 100,04(2) deg, Z = 4 for 7, a = 10,276(3) Angstroem, b = 12,935(3) Angstroem, and c = 14,854(2) Angstroem, β = 96,96(2) deg, Z = 4 for 10, and a = 10,492(2) Angstroem, b = 9,232(3) Angstroem, and c = 27,129(3) Angstroem, β = 98,67(2) deg, Z = 4 for 14.The structures of the Ru complexes are compared with the Fe analogues.In the case of M = Ru and L = (EtO)3P, (MeO)3P, and (i-PrO)3P (9, 11, and 13, respectively) stereoisomers could be detected by 31P-NMR at room temperature, which arise from rotation at the coordinated metal centre.