Reaction #1483058

Reaction equation

Triphenylphosphine

4-Nitroaniline

sodium nitrite

→

4-nitrophenylphosphonium nitrate

Solvents

sodium acetate

Water

ethyl acetate

HCl

water

Conditions

Workup

1. 1
   Otherwere prepared by the method of Horner [Chem. Ber. 1958, 91, 45] and Rieke [J. Am. Chem. Soc. 1976, 98, 6872]
2. 2
   workup.ADDITIONwas added
3. 3
   workup.ADDITIONwas added dropwise
4. 4
   Otherthe water layer separated from the ethyl acetate
5. 5
   Extractionthe aqueous portion extracted twice with ether
6. 6
   ExtractionThe ethyl acetate solution was extracted twice with water
7. 7
   workup.ADDITIONAddition of an aqueous solution of sodium iodide
8. 8
   Otherprecipitated the phosphonium iodide, mp 225-227° C. (Lit. 228.5° C.; Chem. Ber. 1958, 91, 45)
9. 9
   workup.DISSOLUTION4-Nitrophenylphosphonium iodide was dissolved in 5 mL of ethanol
10. 10
    workup.ADDITIONtreated with an aqueous solution of AgNO3
11. 11
    OtherThe silver iodide was removed by filtration
12. 12
    Otherthe solution was evaporated to dryness

Procedure

Non-radioactive standards and compounds used for radiolabeling were prepared by the method of Horner [Chem. Ber. 1958, 91, 45] and Rieke [J. Am. Chem. Soc. 1976, 98, 6872]. 4-Nitroaniline (2.8 g, 0.02 mol) and the molar equivalent of sodium nitrite were dissolved in 10 ml of concentrated HCl acid 10 ml of water at 0° C. Water (20 ml), in which was dissolved sodium acetate (5.6 g), was added. Triphenylphosphine (5.6 g) dissolved in ethyl acetate (80 ml) was added dropwise with stirring. After one hour, the resulting solution was acidified, the water layer separated from the ethyl acetate, and the aqueous portion extracted twice with ether. The ethyl acetate solution was extracted twice with water, the extracts were combined with the other aqueous fraction. Addition of an aqueous solution of sodium iodide precipitated the phosphonium iodide, mp 225-227° C. (Lit. 228.5° C.; Chem. Ber. 1958, 91, 45). 4-Nitrophenylphosphonium iodide was dissolved in 5 mL of ethanol treated with an aqueous solution of AgNO3. The silver iodide was removed by filtration and the solution was evaporated to dryness. Chromatography of the crude salt on silica gel (methylene chloride/methanol (90:10)) afforded pure 4-nitrophenylphosphonium nitrate; mp 215-127° C. Anal. calcd for C24H19N2O5P: C, 64.57. H, 4.29. Found: C, 64.49; H, 4.14.

Source