Pyridine → HCID 9912676, compound

HRID 1416169Notes

Reaction equation

HRID 1416169 reaction equation
[Si]([O:8][C:9]1[CH:14]=[CH:13][C:12]([S:15]([C:18]2[CH:31]=[CH:30][C:21]3[O:22][C:23]([CH3:29])([CH3:28])[C@@:24]4([CH3:27])[O:26][C@H:25]4[C:20]=3[CH:19]=2)(=[O:17])=[O:16])=[CH:11][CH:10]=1)(C(C)(C)C)(C)C.[CH3:32][N:33]1[C:38](=[O:39])[CH:37]=[CH:36][C:35]([OH:40])=[N:34]1.N1C=CC=CC=1>O1CCOCC1>[CH3:32][N:33]1[C:38](=[O:39])[CH:37]=[CH:36][C:35]([O:40][C@H:25]2[C@@:24]([OH:26])([CH3:27])[C:23]([CH3:28])([CH3:29])[O:22][C:21]3[CH:30]=[CH:31][C:18]([S:15]([C:12]4[CH:11]=[CH:10][C:9]([OH:8])=[CH:14][CH:13]=4)(=[O:16])=[O:17])=[CH:19][C:20]2=3)=[N:34]1

Participants

5

Reactant 3

HCID 1049PyridineHCID 57308558HCID 57308558, compoundHCID 178481946HCID 178481946, compound

Product 1

HCID 9912676HCID 9912676, compoundYield 21.2%

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

(3S,4S)-6-(4-tert-Butyidimethylsilyloxyphenyl)sulphonyl-3,4-dihydro-3,4-epoxy-2,2,3-trimethyl-2H-benzo[b]pyran (1.618 g) (see Preparation 14) and 2,3-dihydro-2-methyl-3-oxo-6-hydroxypyridazine (1.33 g) (see J.Org.Chem, 1971, 36, 3372) were suspended in dry 1,4-dioxane (15 ml), pyridine (0.275 ml) was added and the mixture was heated under reflux (a calcium chloride drying tube was attached to the flask) for 3 days. The solvent was removed under reduced pressure and the residue was partitioned between ethyl acetate and water. The organic phase was separated and dried (anhydrous sodium sulphate), the solvent was removed under reduced pressure and the crude product was chromatographed on silica using. 1:99 methanol: ethyl acetate as the eluent to yield (3S,4R)-3,4-dihydro-4-(2,3-dihydro-2-methyl-3-oxopyridazin-6-yl)oxy-3-hydroxy-6-(4-hydroxyphenyl)sulphonyl-2,2,3-trimethyl-2H-benzo[b]pyran (0.352 g) as a white solid. Found: C,58.13; H,5.00; N,5.70. C23H24N2O7S requires C,58.46; H,5.12; N,5.93%.

Workup

  1. temperaturethe mixture was heated
  2. temperatureunder reflux (a calcium chloride drying tube
  3. customfor 3 days
  4. customThe solvent was removed under reduced pressure
  5. customthe residue was partitioned between ethyl acetate and water
  6. customThe organic phase was separated
  7. dry with materialdried (anhydrous sodium sulphate)
  8. customthe solvent was removed under reduced pressure
  9. customthe crude product was chromatographed on silica using

Sources & evidence

ORD record
ord-bfce885c79d54384b8e2f480c181cf56
Source dataset
uspto-grants-1999_06
Patent number
US05912244

Reaction notes

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