82456-41-5Relevant academic research and scientific papers
Metal-templated synthesis of macrocyclic (triphosphine)molybdenum complexes
Diel, Bruce N.,Brandt, Paul F.,Haltiwanger, R. Curtis,Hackney, Michael L. J.,Norman, Arlan D.
, p. 2811 - 2816 (2008/10/08)
Reaction of CH2=CHCH2PH2, CH2=CHCH2CH2PH2, and CH≡CCH2PH2 with (mesitylene)Mo(CO)3 or (cycloheptatriene)Mo(CO)3 yields the complexes (CH2=CHCH2PH2)3Mo(CO)3 (1), (CH2=CHCH2CH2PH2) 3Mo(CO)3 (2), and (CH≡CCH2PH2)3Mo(CO)3 (3), respectively. Reaction of CH2=CHCH2PH2 and CH≡CCH2PH2 with cis-(piperidine)2Mo(CO)4 yields cis-(CH2=CHCH2PH2)2Mo(CO) 4 (4) and cis-(CH≡CCH2PH2)2Mo(CO)4 (5). Free-radical-initiated cyclooligomerization of 1 and 2 yields the triligated macrocyclic secondary-phosphine complexes fac-[HP(CH2)3]3Mo(CO)3 (6) and fac-[HP-(CH2)4]3Mo(CO)3 (7). Under similar conditions, reaction of 4 yields an acyclic diphosphine complex characterized tentatively as cis-[H2P(CH2)3PH(CH2CH=CH 2)]Mo(CO)4 (8). Compounds 1-7 and 10 have been characterized by spectral (31P, 13C, and 1H NMR and IR and mass) data. 6 has been characterized in the solid state by single-crystal X-ray analysis. Crystalline 6 is monoclinic, space group P21/c, with a = 12.606 (3) ?, b = 8.508 (2) ?, c = 15.420 (2) ?, β = 93.39 (2)°, do = 1.61 g/mL, dc = 1.616 g/mL, Z = 4, and R = 0.026, Rw = 0.032 for 2685 unique observed reflections. In the crystal, the P3 macrocycle assumes a partial crown structure in which the complex has approximate Cs point symmetry. 31P NMR spectral studies of the cyclooligomerization of 1 show the partially cyclized intermediates formed prior to 6. The macrocyclic complexes 6 and 7 are kinetically stable, showing no sign of ligand displacement in reactions with Ph3P, PF3, KCN, or P(OMe)3.
