Diethyl disulfide → (4R,9aR)-7-Ethylsulfanyl-4,6-dimethyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester

HRID 1272148Notes

Reaction equation

HRID 1272148 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH2:20][C@@H:19]([CH3:21])[N:18]2[C@H:10]([CH2:11][C:12]3[C:17]2=[N:16][C:15]([CH3:22])=[C:14](Br)[CH:13]=3)[CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].C([Li])(C)(C)C.[CH2:29]([S:31]SCC)[CH3:30]>C(OCC)C>[C:1]([O:5][C:6]([N:8]1[CH2:20][C@@H:19]([CH3:21])[N:18]2[C@H:10]([CH2:11][C:12]3[C:17]2=[N:16][C:15]([CH3:22])=[C:14]([S:31][CH2:29][CH3:30])[CH:13]=3)[CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2]

Participants

5

Conditions

Temperature
-78 °C

Procedure

A solution of 0.50 g (1.31 mmol) (4R,9aR)-7-bromo-4,6-dimethyl-3,4,9,9a-tetrahydro-1H-2,4a,5-triaza-fluorene-2-carboxylic acid tert-butyl ester (example 6, intermediate) in 30 mL diethyl ether was cooled to −100° C. and 1.05 mL tert-butyl-lithium (1.57 mmol; 1.5M solution in n-pentane) was added dropwise. After 15 min. diethyl disulfide was added and the reaction was stirred at −78° C. for 1 h. The reaction mixture was quenched with 10% aqueous citric acid solution and extracted three times with ethyl acetate. The combined organic layers were washed with brine, dried over magnesium sulfate, filtered and evaporated. The residue was purified by column chromatography over silica gel (0.030–0.063 mm) with ethyl acetate:n-hexane (1:4) as eluant to give the product as a light yellow solid (57.2%).

Workup

  1. customThe reaction mixture was quenched with 10% aqueous citric acid solution
  2. extractionextracted three times with ethyl acetate
  3. washThe combined organic layers were washed with brine
  4. dry with materialdried over magnesium sulfate
  5. filtrationfiltered
  6. customevaporated
  7. customThe residue was purified by column chromatography over silica gel (0.030–0.063 mm) with ethyl acetate:n-hexane (1:4) as eluant

Sources & evidence

ORD record
ord-5320ad194d7f49fe92bb407770f5d305
Source dataset
uspto-grants-2007_04
Patent number
US07208494B2

Reaction notes

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