9-Fluorenylmethyl chloroformate → HCID 22872534, compound

HRID 1779970Notes

Reaction equation

HRID 1779970 reaction equation
COC1[C@@H](C(C)C)N=[C:6]([O:12][CH3:13])[C@H:7]([CH2:9][O:10][CH3:11])[N:8]=1.[C:17](Cl)([O:19][CH2:20][CH:21]1[C:33]2[C:28](=[CH:29][CH:30]=[CH:31][CH:32]=2)[C:27]2[C:22]1=[CH:23][CH:24]=[CH:25][CH:26]=2)=[O:18].C([O-])(O)=[O:36].[Na+]>O1CCOCC1.O.C(Cl)(Cl)Cl>[CH:32]1[C:33]2[CH:21]([CH2:20][O:19][C:17]([NH:8][C@@H:7]([CH2:9][O:10][CH3:11])[C:6]([O:12][CH3:13])=[O:36])=[O:18])[C:22]3[C:27](=[CH:26][CH:25]=[CH:24][CH:23]=3)[C:28]=2[CH:29]=[CH:30][CH:31]=1

Participants

7

Reactant 3

HCID 343679-Fluorenylmethyl chloroformateHCID 516892Sodium BicarbonateHCID 57294432HCID 57294432, compound

Product 1

HCID 22872534HCID 22872534, compound

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 6212ChloroformSolventHCID 312751,4-DioxaneSolvent2×

Procedure

To a solution of (2R,5S)-3,6-dimethoxy-5-(methoxymethyl)-2-isopropyl-2,5-dihydropyrazine (2.1 g, 9.2 mmol) in dioxane (18 ml ) 1M HCl (18.4 ml ), 18.4 mmol) was added and the mixture stirred at ambient temperature overnight. The volatile components were evaporated, the residue redissolved in dioxane and again evaporated. The crude residue was dissolved dioxane and FmocCl (5.71 g, 2.21 mmol) was added. After 2 minutes 1M NaHCO3 (44.2 ml, 44.2 mmol) was added. After 15 minutes the mixture was diluted with water (50 ml) and CHCl3 (100 ml). The layers were separated and the aqueous phase extracted with CHCl3 (2×75 ml). The combined organic layer was dried (Na2SO4), concentrated and purified by flash chromatography (silica gel; hexane: ethyl acetate 2:1).

Workup

  1. customThe volatile components were evaporated
  2. dissolutionthe residue redissolved in dioxane
  3. customagain evaporated
  4. additionwas added
  5. customThe layers were separated
  6. extractionthe aqueous phase extracted with CHCl3 (2×75 ml)
  7. dry with materialThe combined organic layer was dried (Na2SO4)
  8. concentrationconcentrated
  9. custompurified by flash chromatography (silica gel; hexane: ethyl acetate 2:1)

Sources & evidence

ORD record
ord-5073e6f75b62487185cd8679160e8b71
Source dataset
uspto-grants-1997_05
Patent number
US05629293

Reaction notes

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