No abstract

Gray selenium (0.96 g, 12.16 mmol) and a trace of iodine as catalyst for polyaelenide formation were added to a mixture of Li and Se in a molar ratio of 1.1 (0.26 g = 1.52 mmol) and [Ph,PNPPh,]CI (1.75 g, 3.04 mmol). The resulting mixture was heated for 3 h in 30mL of DMF at 100°C. After cooling. the reaction mixture was filtered to remove LiCl and unreacted selenium, 20 mL of ether was added, and the solution was allowed to stand for 2 d. The resulting black single crystals were filtered, washed with EtOH, and dried briefly in vacuo. Yield 2.1 g (72%, based on [Ph,PNPPh,]Cl).

steht aus einem Singulett (6 = 44.2) mit schwachen 199Hg-Satelliten (JP-HE = 603 Hz). Die fur Komplexe mit direkten P-Hg-Bindungen typischen J,-,,-Werte liegen im Bereich von ca. 4300 bis 5700 H z [~*~I .Die 31P{'H}-NMR-Daten sind daher eindeutig unvereinbar rnit einer direkten P-HgBindung. Die H-NMR-Daten zeigen die Anwesenheit von Ph,PCH,PPh, mit 6 = 7. 40H, Ph,P)

No abstract

Hydrolytic Stable Ammonium Salts of Sulfonated Organic Phosphites and their Use as Cocatalysts in the Rhodium‐catalyzed Hydroformylation of Olefins Ammonium salts of sulfonated organic phosphites, which are resistant to hydrolysis, have been prepared by transesterification of triphenylphosphite with mono‐ammonium salt of p‐hydroxyphenylsulfonic acid in yields between 66 and 76%. A mixture containing triisooctylammonium salts of sulfonated triphenylphosphite [TPPp‐SO3HN(i‐octyl)3] was submitted to a test for stability to hydrolysis. The time required for hydrolysis of 7.4% of the TPPp‐SO3HN(i‐octyl)3 was 3 hours under drastic conditions. Triphenylphosphite was in the same test hydrolyzed quantitatively within three hours. Tetradec‐1‐ene was hydroformylated by means of the catalytic systems consisting of rhodium‐2‐ethylhexanoate with either TPPp‐SO3HN(i‐octyl)3, triphenylphosphite (TPPp) or triphenylphosphine (TPP) at 125°C, 0.6 MPa and a rhodium concentration of 50 ppm. Higher reaction selectivities for linear aldehydes were achieved with the rhodium/TPPp‐SO3HN(i‐octyl)3 catalytic system. Reaction rates increased with the Rh/TPPp‐SO3HN(i‐octyl)3 catalyst at lower temperature (110°C). Using this catalyst at 110°C, higher yields are achieved than with the Rh/TPP or Rh/TPPp catalysts. Hex‐1‐ene was hydroformylated by using the catalytic systems Rh4(CO)12 with TPPp‐SO3HN(i‐octyl)3, Rh4(CO)12 TPP or Rh4 (CO)12 with TPPp at 125°C, 2,5 MPa and a rhodium concentration of 20 ppm. This confirms the above experiments which indicated that higher linear: branched aldehyde ratios were obtained with the rhodium/TPPp‐SO3HN(i‐octyl)3 catalyst.