156475-51-3Relevant academic research and scientific papers
Synthesis and X-ray crystal structure of trans-Mo(CO)4{Ph2P(CH2CH2O) 4CH2CH2PPh2-P,P′}, a molecular gyroscope formed by trans coordination of a bis(phosphine) ligand in an octahedral metal complex
Gray, Gary M.,Duffey, Christina H.
, p. 1542 - 1544 (1994)
Photolysis of cis-Mo(CO)4{Ph2P(CH2CH2O) 4-CH2CH2PPh2-P,P′} (1) in THF under nitrogen gives trans-Mo(CO)4{Ph2P(CH2CH2O) 4CH2CH2PPh2-P,P′} (2). Complex 2 is the first example of a metalla crown ether in which the α,ω-bis(phosphorus donor)polyether ligand is trans coordinated. It is also a rare example of an octahedral complex with a trans-spanning bis(phosphine) ligand.
Metallacrown ethers with trans-tetracarbonylmolybdenum(0) centers
Duffey, Christina H.,Lake, Charles H.,Gray, Gary M.
, p. 199 - 210 (2008/10/08)
Photolysis of the cis-Mo(CO)4{Ph2P(CH2CH2O) nCH2CH2PPh2-P,P′}, (1, n = 3; 2, n = 4; 3, n = 5) metallacrown ethers in tetrahydrofuran under nitrogen gives moderate yiel
Size-selective reactions of cis-Mo(CO)4{Ph2P(CH2CH2O) nCH2CH2PPh2-P,P′} (n = 4, 5) metallacrown ethers with mercury(II) salts. Crystal structure of cis-Mo(CO)4-{μ-Ph2P(CH2CH2O) 5CH2CH2PPh ...
Gray, Gary M.,Duffey, Christina H.
, p. 245 - 250 (2008/10/08)
Full title: Size-selective reactions of cis-Mo(CO)4{Ph2P(CH2CH2O) nCH2CH2PPh2-P,P′} (n = 4, 5) metallacrown ethers with mercury(II) salts. Crystal structure of cis-Mo(CO)4-{μ-Ph2P(CH2CH2O) 5CH2CH2PPh 2-P,P′,O,O′,O″,O?,O′?}· HgCl2, an unusual bimetallic complex containing a molecular cleft. The reactions of mercury(II) salts with cis-Mo(CO)4{Ph2P(CH2CH2O) nCH2CH2PPh2-P,P′} (n = 5 (1), 4 (2)) metallacrown ethers are surprisingly complex, and the product depends upon the size of the metallacrown ether ring and the anion in the mercury(II) salt. The reaction of HgCl2 and 1 gives the bimetallic metallacrown ether complex, cis-Mo(CO)4{μ-Ph2P(CH2CH2O) 5CH2CH2PPh 2-P,P′,O,O′,O″,O?,O′?}· HgCl2, 3, because the metallacrown ether ring is sufficiently large to accommodate the Hg2+. The X-ray crystal structure of 3 (triclinic space group P1, a = 10.387(2) A?, b = 13.0359(7) A?, c = 17.710(3) A?, α = 69.401(7)°, β = 81.32(1)°, γ = 87.15(1)°; V = 2218.8 A?3; Z = 2;R = 5.82; Rw = 7.19; GOF = 1.996 for 497 parameters and 7737 out of 9505 unique reflections) has been determined. The coordination environment of the Hg2+ is a hexagonal bipyramid with one missing equatorial ligand, axial chlorides, and equatorial ether oxygens. The open coordination site points toward the molybdenum, and the Mo-Hg distance is 6.8854(6) A?. In contrast, the reaction of HgCl2 and 2 results in the isomerization of 2 to trans-Mo(CO)4{Ph2P(CH2CH2O) 4CH2CH2PPh2-P,P′}, 4. The Hg2+, which is too large to fit in the metallacrown ether ring in 2, catalyzes this isomerization, perhaps via coordination to the metallacrown ether and a lone pair on one of the carbonyl oxygens. Finally, the reaction of Hg(NO3)2·H2O and 1 results in the oxidation of the molybdenum carbonyl complex and the formation of a Hg2+ complex of Ph2P(CH2CH2O)5CH2CH 2PPh2. This mercury complex is not formed when Hg(NO3)2·H2O is stirred with Ph2P(CH2CH2O)5CH2CH 2PPh2 indicating that the metallacrown ether is required for the reaction to occur.
cis-Mo(CO)4{Ph2P(CH2CH2O) nCH2CH2PPh2} (n = 3-5) metallacrown ethers. X-ray crystal structure of cis-Mo(CO)4{Ph2P(CH2CH2O) 3CH2CH2PPh2}
Varshney, Ashima,Gray, Gary M.
, p. 1748 - 1754 (2008/10/08)
A series of Ph2P(CH2CH2O)nCH2CH 2PPh2 (1, n = 3; 2, n = 4; 3, n = 5) ligands and their cis-Mo(CO)4{Ph2P-(CH2CH2O) nCH2CH2PPh2) (4, n = 3; 5, n = 4; 6, n = 5) complexes have been prepared. Multinuclear NMR and IR spectroscopic studies of these complexes indicate that a single Mo complex, with the ligands cis coordinated to the Mo through the PPh2 groups, is formed with each ligand. The complexes have been titrated with LiBF4 and NaBPh4, and the titrations have been followed by 31P NMR spectroscopy. These studies indicate that 5 binds much more strongly to Li+ than to Na+, but 6 binds more strongly to Na+ than to Li+. Bimetallic complexes were isolated from the titration solutions. With 6, 1:1 adducts were obtained with both LiBF4 and NaBPh4, whereas with 5, a 1:1 adduct was obtained with LiBF4 and a 2:1 adduct was obtained with NaBPh4. These results demonstrate that the metallacrown ethers exhibit definite size selectivities toward the alkali-metal cations. The cis-Mo-(CO)4{Ph2P(CH2CH2O) nCH2CH2PPh2} (n = 3-5) complexes react with methyllithium and phenyllithium to yield cis-Mo-(CO)4(Ph2PCH=CH2)2. This result is surprising because related Mo(CO)4 complexes of bis(phosphinite)- and bis(phosphite)-polyether ligands react with methyllithium and phenyllithium to yield acetyl and benzoyl complexes, respectively. The X-ray crystal structure of cis-Mo(CO)4{Ph2P(CH2CH2O) 3CH2CH2PPh2} (4) is also reported. The complex crystallizes in the monoclinic space group P21/n (a = 22.219 (1), b = 14.8175 (4), c = 10.680 (1) ?; β = 98.523°; V = 3477.2 ?3; z = 4). The molybdenum is in a slightly distorted octahedral coordination geometry with a P-Mo-P angle of 93.78 (2)°. The metallacrown ether ring is distorted from the symmetric solution conformation primarily due to different rotations of the diphenylphosphino groups about the molybdenum-phosphorus bonds. The three oxygens in the metallacrown ether are at the vertices of an isosceles triangle, and the plane formed by these oxygens is perpendicular to that formed by the molybdenum and the two phosphorus atoms.
