Samarium diiodide characterization

Into a solution of residue 59 (101 mg, 0.1 mmol) in 20 mL of dry toluene, kept at 60°C, was syringed, during 18 h and under argon, a freshly prepared solution of samarium diiodide in benzene-HMPA (9 1, v/v 6.3 mL, 0.51 mmol) which has been diluted with 3.8 mL of dry benzene. The solvents were distilled off under reduced pressure, and the residue was taken up in 10 mL of diethyl ether. The ether solution was washed with 10% aqueous solution of sodium bisulfite, then water, dried (MgS04), and concentrated. The crude product was dissolved in 1.5 mL of tetrahydrofuran and treated during 30 min at room temperature with 1.5 mL of a 40% aqueous solution of HF. The solution was neutralized with solid sodium carbonate, and concentrated. Flash chromatography on silica gel (cyclohexane-ethyl acetate, 3 1 to 1 2) afforded the product 80 (40.6 mg, 50%), a single isomer, as an amorphous solid. It was characterized by its diacetate [a]D +36° (c 4.0, CHClj). 

Di-0-ter -butyldimethylsilyl-3,4-0-isopropylidene-D-glucitol on Swem oxidation then treatment with samarium diiodide gives the L-cA/ro-derivative 68 together with a small amount of the myo-isomer. Compound 68 was further converted into its hexaacetate for characterization purposes as well as into conduritol F tetraacetate. ... 

Treatment of thulium diiodide with substituted phospholide and arsolide salts afforded stable bis(phospholyl)- and bis(arsolyl)thulium(ll) complexes (Scheme 201) as green solids, that were characterized by multinuclear NMR and X-ray crystal structures. The latter clearly revealed the beneficial effects of the steric and electronic properties of crowded phospholyl and arsolyl ligands for the stabilization of divalent thulium.727 Several other homoleptic samarium(ll) and thulium(n) phospholyl sandwich complexes containing the 2,5-di-/-butyl-3,4-dimethylphospholide (=dtp) or 2,5-bis(trimethylsilyl)-3,4-dimethylphospholide (=dsp) ligand have been synthesized and structurally characterized. X-ray studies revealed that [Sm(dtp)2]2 and [Sm(dsp)2]2 are both dimeric in the solid state due to... 

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