Pyridine → 2-(4-Nitrobenzyl)-1,3,2-dioxaphosphinane 2-oxide

HRID 861869Notes

Reaction equation

HRID 861869 reaction equation
C(Cl)(=O)C(Cl)=O.[N+:7]([C:10]1[CH:20]=[CH:19][C:13]([CH2:14][P:15](=[O:18])([OH:17])[OH:16])=[CH:12][CH:11]=1)([O-:9])=[O:8].N1C=C[CH:24]=[CH:23][CH:22]=1>O1CCCC1>[N+:7]([C:10]1[CH:20]=[CH:19][C:13]([CH2:14][P:15]2(=[O:16])[O:17][CH2:24][CH2:23][CH2:22][O:18]2)=[CH:12][CH:11]=1)([O-:9])=[O:8]

Participants

5

Reactant 3

HCID 1049PyridineHCID 65578Oxalyl chlorideHCID 5180708(4-Nitro-benzyl)-phosphonic acid

Product 1

HCID 113458932-(4-Nitrobenzyl)-1,3,2-dioxaphosphinane 2-oxideYield 26.4%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
-78 °C

Procedure

Oxalyl chloride (22.09 g) was added dropwise to a mixture of 4-nitrobenzylphosphonic acid (17.99 g), pyridine (13.76 g) and tetrahydrofuran (500 ml) at -78° C. After this mixture was stirred at -78° C. for 30 minutes and then at room temperature for 1.5 hours, the insoluble solid was filtered off. The filtrate was concentrated under reduced pressure; the residual oil was dissolved in tetrahydrofuran (500 ml). To this solution, a solution of 1,3-propanediol (2.58 g) in acetonitrile (30 ml) was added dropwise at -78° C. over a period of 15 minutes. Pyridine (5.62 g) was then added dropwise at the same temperature over a period of 5 minutes; the mixture was stirred at room temperature for 15 hours. After the insoluble substance was filtered off, the filtrate was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography and eluted with ethyl acetate-chloroform-methanol (10:10:1, v/v) to yield 2-(4-nitrobenzyl)-1,3,2-dioxaphosphorinan-2-oxide (5.62 g, 26%), which was then recrystallized from ethanol-hexane to yield colorless needles having a melting point of 144°-145° C.

Workup

  1. waitat room temperature for 1.5 hours
  2. filtrationthe insoluble solid was filtered off
  3. concentrationThe filtrate was concentrated under reduced pressure
  4. dissolutionthe residual oil was dissolved in tetrahydrofuran (500 ml)
  5. additionTo this solution, a solution of 1,3-propanediol (2.58 g) in acetonitrile (30 ml) was added dropwise at -78° C. over a period of 15 minutes
  6. additionPyridine (5.62 g) was then added dropwise at the same temperature over a period of 5 minutes
  7. stirringthe mixture was stirred at room temperature for 15 hours
  8. filtrationAfter the insoluble substance was filtered off
  9. concentrationthe filtrate was concentrated under reduced pressure
  10. washeluted with ethyl acetate-chloroform-methanol (10:10:1

Sources & evidence

ORD record
ord-31ecd93b7ace4edcb03946a8fc514705
Source dataset
uspto-grants-1998_02
Patent number
US05716944

Reaction notes

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