Ellen A. Keiter

Interpretation of electric field gradients at deuterium as measured by solid-state NMR spectroscopy

Abstract A simple interpretative scheme is presented to describe the deuterium quadrupole coupling constant and asymmetry parameter in a wide variety of chemical environments.

On the synthesis and 31P{1H} NMR spectrum of (CO) 5W(μ-PPh2CH2PPh2) W(CO)5

The dimetallic complex, (CO)5W(μ-PPh2CH2PPh2)W(CO)5, is synthesized from either a 2:1 mixture of (CO)5W(NCMe) and (CO)5W(η1-PPh2CH2PPh2) or a 3:1 mixture of (CO)5W(NCMe) and PPh2CH2PPh2 in toluene at 60°C. The coupling constants, 2Jpp′ = 22.9 Hz, 1JWP = 246.9 Hz and3JWP′ = 4.5Hz are consistent with those reported in the literature for similar complexes. The complex (CO)5W(η1-PPh2CH2PPh2) is stable with respect to chelation at room temperature.

The Synthesis of BIS(Phosphine)Tricarbonyliron(O) Complexes

Abstract The high-yield synthesis of trans-Fe(CO)3L2 (L = PPh3, PPh2 H, P(n-Bu)3, PPh2 CH=CH, PPh2Me) can be acheived in one step by the reaction of Fe(CO), with L and NaOH in refluxing n-butanol. The reaction is selective for trans disubstitued complexes and is complete in 2 h.

Crystal structure of trans-W2(CO)6(PPh2H)2(μ2-PPh2)2

The molecular structure of trans-W2(CO)6(PPh2H)2(μ2-PPh2)2 was determined by X-ray diffraction analysis. The two tungsten centers, bridged by two diphenylphosphido ligands, are separated by 3.0667(6) Å with W–P–W angles of 77.10(5) and 77.08(5)○. Average tungsten–phosphorus bond distances are 2.461(17) and 2.4576(21) Å for bridging and terminal phosphorus groups, respectively, with a range of 0.037 Å for the former and 0.001 Å for the latter. The complex crystallizes in the monoclinic space group P21/c with a = 19.282(4) Å, b = 12.158(2) Å, c = 21.294(9) Å, β = 92.821(4)○, and Z = 4.