Toluene → HCID 53751189, compound

HRID 2379032Notes

Reaction equation

HRID 2379032 reaction equation
C[O:2][P:3]([O:6][CH3:7])[O:4][CH3:5].[C:8]1([CH3:14])[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1>>[CH3:5][O:4][P:3]([CH2:14][C:8]1[CH:13]=[C:12]2[C:11]([CH:10]=[CH:9][C:8]([CH2:14][P:3](=[O:2])([O:6][CH3:7])[O:4][CH3:5])=[CH:13]2)=[CH:10][CH:9]=1)(=[O:2])[O:6][CH3:7]

Participants

3

Reactant 2

HCID 1140Toluene2×HCID 8472Trimethyl phosphite2×

Product 1

HCID 53751189HCID 53751189, compound

Procedure

The crude product from Example 27(a), a 1:1 mixture of dibromo and tribromo products (assumed to contain 0.010 mole of each), is dissolved in toluene (25 mL) and trimethylphosphite (10 mL, 0.085 mole). The mixture is heated at reflux temperature for 24 h after which excess toluene and trimethylphosphite are removed under reduced pressure. The dark red residue is chromatographed (400 g of 40-63 μm silica gel, 10% methanol in chloroform, 50 mL fractions), with fractions 31-36 containing 4.90 g of material which is rechromatographed (400 g of 40-63 μM silica gel, ethyl acetate, 50 mL fractions). The column is eluted with ethyl acetate (1 L) and then with 10% methanol in ethyl acetate. Fractions 70-92 (2.09 g) still contained two components (tlc, silica gel, 10% CH3OH--CHCl3, 4% CH3OH--CH2Cl2) and is chromatographed (400 g of 40-63 μM silica gel, CH2Cl2, 50 mL fractions) a third time. Elution is with 4% CH3OH--CH2Cl2 through fraction 80 and then with 10% CH3OH--CH2Cl2. Fractions 41-47 contained the desired diphosphonate (1.418 g) as a viscous oil which slowly solidifies. Crystallization from acetone-hexane give crystals, mp 87°-88° C.

Workup

  1. temperatureThe mixture is heated
  2. customare removed under reduced pressure
  3. customThe dark red residue is chromatographed (400 g of 40-63 μm silica gel, 10% methanol in chloroform, 50 mL fractions)
  4. customwith fractions 31-36 containing 4.90 g of material which is rechromatographed (400 g of 40-63 μM silica gel, ethyl acetate, 50 mL fractions)
  5. washThe column is eluted with ethyl acetate (1 L)
  6. customis chromatographed (400 g of 40-63 μM silica gel, CH2Cl2, 50 mL fractions) a third time
  7. washElution
  8. customCrystallization from acetone-hexane
  9. customgive crystals, mp 87°-88° C.

Sources & evidence

ORD record
ord-b06c433572e84efc9a01534c654b1dfc
Source dataset
uspto-grants-1994_11
Patent number
US05360797

Reaction notes

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