{[Bis(dimethylamino)boryl]methyl}dimethylphosphane as ligand in transition metal complexes

Article abstract of DOI:10.1016/S0022-328X(97)00339-2

The new α,ω-[phosphanyl(organyl)]borane Me₂PCH₂B(NMe₂)₂ (8) was obtained in good yield by the reaction of ClB(NMe₂)₂ with LiCH₂PMe₂. Compound 8 forms the transition metal complexes [(CO)₅Cr{Me₂PCH ₂B(NMe₂)₂}] (9), [(MeC₅H₄)Mn(CO)₂{Me₂PCH₂B(NMe₂)₂}] (10), and [(CO)₄Fe{Me₂PCH₂B(NMe₂)₂)] (11), which were isolated as highly volatile liquids in high yields. Complex 11 easily underwent exchange reactions of the Me₂N substituents which led to derivatives with threefold coordinated boron such as [(CO)₄Fe{Me₂PCH₂B(OMe)₂}] (13), and [(CO)₄Fe{Me₂PCH₂B(NMe₂)Cl)] (14), or to a compound with tetrafold coordinated boron, [(CO)₄Fe{Me₂PCH₂BCl₂(NHMe₂)}] (15). Li[(CO)₄Fe(Me₂PCH₂BH₃)] (16), cis,trans-[{(CO)₄Fe(Me₂PCH₂BH₂)}₂] (17), and [(CO)₄Fe{Me₂PCH₂BH₂(2,4,6-Me₃C₅H₂N)}] (18) were obtained from 13 by corresponding substitution of the MeO groups. The addition of HSiPh₃ to the iron center was achieved by photolysis of 13, giving [(CO)₃FeH(SiPh₃){Me₂PCH₂B(OMe)₂}] (19). [(CO)₅Cr{Me₂PCH₂B(OMe)₂}] (12), the chromium analogue of 13, was obtained from the reaction of [(CO)₅Cr{Me₂PCH₂B(NMe₂)₂}] (9) with MeOH. The structure of compound 19 was determined by single crystal X-ray diffraction.