Lead dioxide → HCID 178468128, compound

HRID 2057553Notes

Reaction equation

HRID 2057553 reaction equation
[C:1]([O:5][C:6]([C:8]1[N:13]2[C:14](=[O:17])[C@@H:15]([NH2:16])[C@H:12]2[S:11][CH2:10][C:9]=1[C:18]([CH2:28][PH:29]([O:31][C:32]([CH3:35])([CH3:34])[CH3:33])=[O:30])([S:22][C:23]1[NH:27][N:26]=[N:25][N:24]=1)[O:19][CH2:20][CH3:21])=[O:7])([CH3:4])([CH3:3])[CH3:2].C(C1C=C(C=C(C(C)(C)C)C=1O)[CH:43]=[O:44])(C)(C)C.[Pb](=O)=O>C1C=CC=CC=1.ClCCCl>[C:1]([O:5][C:6]([C:8]1[N:13]2[C:14](=[O:17])[C@:15]([NH2:16])([O:44][CH3:43])[C@H:12]2[S:11][CH2:10][C:9]=1[C:18]([CH2:28][PH:29]([O:31][C:32]([CH3:34])([CH3:33])[CH3:35])=[O:30])([S:22][C:23]1[NH:27][N:26]=[N:25][N:24]=1)[O:19][CH2:20][CH3:21])=[O:7])([CH3:4])([CH3:2])[CH3:3]

Participants

6

Reactant 3

HCID 14793Lead dioxideHCID 732193,5-Di-tert-butyl-4-hydroxybenzaldehydeHCID 178468125HCID 178468125, compound

Product 1

HCID 178468128HCID 178468128, compound

Reagents, catalysts & solvents 2

HCID 111,2-DichloroethaneSolventHCID 241BenzeneSolvent

Procedure

A solution of 1.32 g (2.4 mmol) of 7β-amino-3-(1-ethoxy-t-butoxyphosphinylmethyltetrazol-5-ylthiomethyl)-3-cephem-4-carboxylic acid t-butyl ester and 0.56 g (2.4 mmol) of 3,5-di-t-butyl-4-hydroxybenzaldehyde in 100 ml of dry benzene is refluxed for 4 hours under a Dean-Stark trap. The solution is evaporated under reduced pressure to leave a residue which is dissolved in 100 ml of 1,2-dichloroethane and cooled to ca. 5° in an ice bath. Three grams of freshly prepared lead dioxide is added in portions over 20 minutes until the starting material is completely consumed. The mixture is filtered through Celite and the filter cake is washed with two 20 ml portions of cold 1,2-dichloroethane. The filtrate is treated with 25 ml of methanol (distilled from magnesium) and the reaction mixture is allowed to stand at room temperature until complete consumption of the oxidized intermediate and formation of a new slower-moving product is shown by thin layer chromatography. The mixture is evaporated and the residue is dissolved in 30 ml of methanol and treated with 2.5 g of Girard reagent T (trimethylaminoacetohydrazide chloride). The reaction mixture is stirred at room temperature for 3 hours, then evaporated to give a residue which is partitioned between ethyl acetate and 20% sodium chloride solution. The organic phase is washed with 10% sodium chloride solution and saturated sodium chloride solution. The organic phase is dried (MgSO4), filtered and evaporated to dryness to give 7β-amino-7α-methoxy-3-(1-ethoxy-t-butoxyphosphinylmethyltetrazol-5-ylthiomethyl)-3-cephem-4-carboxylic acid t-butyl ester.

Workup

  1. customThe solution is evaporated under reduced pressure
  2. customto leave a residue which
  3. temperaturecooled to ca. 5° in an ice bath
  4. customis completely consumed
  5. filtrationThe mixture is filtered through Celite
  6. washthe filter cake is washed with two 20 ml portions of cold 1,2-dichloroethane
  7. additionThe filtrate is treated with 25 ml of methanol (distilled from magnesium)
  8. customto stand at room temperature until complete consumption of the oxidized intermediate and formation of a new slower-moving product
  9. customThe mixture is evaporated
  10. dissolutionthe residue is dissolved in 30 ml of methanol
  11. additiontreated with 2.5 g of Girard reagent T (trimethylaminoacetohydrazide chloride)
  12. customevaporated
  13. customto give a residue which
  14. customis partitioned between ethyl acetate and 20% sodium chloride solution
  15. washThe organic phase is washed with 10% sodium chloride solution and saturated sodium chloride solution
  16. dry with materialThe organic phase is dried (MgSO4)
  17. filtrationfiltered
  18. customevaporated to dryness

Sources & evidence

ORD record
ord-f94a03cc444f45749413ac73e2b5ecad
Source dataset
uspto-grants-1980_07
Patent number
US04211703

Reaction notes

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