OP Ph Research Articles

A new diphosphinite derived from cyclohexane-1,4-diol: oxidation reactions, metal complexes, P–O bond cleavage and X-ray crystal structures of Ph 2P(E)O(C 6H 10)OP(E)Ph 2 (E = S, Se)

The reaction of cyclohexane-1,4-diol with chlorodiphenylphosphine affords bis(phosphinite), Ph 2PO(C 6H 10)OPPh 2 ( 1) in good yield. The bis(phosphinite) ( 1) reacts with H 2O 2, elemental sulfur or selenium to give the corresponding dichalcogenide; the structures of the disulfide ( 3) and diselenide ( 4) derivatives are confirmed by X-ray crystal structure analysis. The reaction of 1 with phosphoryl azide, N 3P(O)(OPh) 2 gives the phosphinimine derivative, (PhO) 2(O)PN PPh 2O(C 6H 10)OPh 2P NP(O)(OPh) 2 ( 5) in quantitative yield. Treatment of the ligand 1 with CpRu(PPh 3) 2Cl results in a bis(phosphinite) bridged dinuclear complex, [CpRuCl(PPh 3)] 2(μ-PPh 2O(C 6H 10)OPPh 2) ( 7) whereas the reaction of 1 with Pd(II) and Pt(II) derivatives afford cis-chelate complexes, [MCl 2{Ph 2PO(C 6H 10)OPPh 2}] (M = Pd, 8; Pt, 9). The reaction of 1 with Mo(CO) 6 in the presence of TMNO · 2H 2O does not give the expected cis-[Mo(CO) 4{Ph 2PO(C 6H 10)OPPh 2}]; instead a cubane-shaped tetranuclear molybdenum(V) complex, [Mo 4O 4(μ 3-O) 4 (μ-O 2PPh 2) 4] ( 6) was obtained due to water assisted cleavage of P–O bonds.

Effect OP PH, orgrnic matter and plant growth on the movement of iron in soils

Abstract The aim of this work was to study the effect of soil pH value and organic matter decomposition products on the diffusion of Fe. A soil‐block technique was used to determine the magnitude of Fe diffusion added as FeSO4 or FeEDDHA to alkaline and acid soil samples previously enriched with alfalfa residues (4%) and incubated for different periods. Results indicated a remarkable increase in the DTPA‐extractable Fe in the layer of fertilizer application and in the successive two soil sections when the inorganic form of Fe was added to the natural acid soil having originally 2% organic matter. The increase in the extractable Fe fron FeSO4, treatment to the alkaline soil was evident only when the soil was enriched with organic matter and incubated for 3 months. The FeEDDHA diffused in about the same magnitude in all soil samples. A new technique of a combined sand culture and a soil‐block was also designed to study the effect of plant on the movement of Fe by diffusion and mass flow. Results showed a si...