Hydrochloric Acid → 1-Benzylisatin

HRID 1297751Notes

Reaction equation

HRID 1297751 reaction equation
[NH:1]1[C:11]2[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=2)[C:4](=[O:5])[C:2]1=[O:3].CC(C)([O-])C.[K+].C1COCC1.[CH2:23](Br)[C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1.Cl>CN(C=O)C>[CH2:23]([N:1]1[C:11]2[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=2)[C:4](=[O:5])[C:2]1=[O:3])[C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1

Participants

7

Reactant 5

HCID 313Hydrochloric AcidHCID 7054IsatinHCID 7498Benzyl BromideHCID 8028TetrahydrofuranHCID 23665647Potassium tert-butoxide

Product 1

HCID 2647341-BenzylisatinYield 113.8%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

Dissolve isatin (7.36 g, 50 mmol) in anhydrous DMF (100 mL) under nitrogen and cool in an ice bath. Treat with 1M potassium tert-butoxide in THF (53 mL, 53 mmol) stir 15-20 min. Add benzyl bromide (6.2 mL, 52.5 mmol) and after 10 min remove bath and allow to warm to room temperature over 16 h. Pour into 1N HCl and wash with ethyl acetate (500 mL). Wash ethyl acetate with 1N HCl (150 mL) and then wash combined acidic portions with more ethyl acetate (150 mL). Wash the combined organic portions with brine (2×150 ml), dry (MgSO4), filter and concentrate in vacuo to give 13.5 g of an orange solid. Triturate in diethyl ether and filter to give 10.0 g (84%) of the title compound. MS (ES): m/z=238 (M+1); 1H NMR(CDCl3): δ7.64 (dd, J=7.6 Hz, J=1 Hz, 1H), 7.5 (dt, J=7.8 Hz, J=1.3 Hz, 1H), 7.37 (m, 5H), 7.12 (t, J=7.6 Hz, 1H), 6.80 (d, J=8.0 Hz, 1H), 4.97 (s, 2H).

Workup

  1. temperaturecool in an ice bath
  2. washwash with ethyl acetate (500 mL)
  3. washWash ethyl acetate with 1N HCl (150 mL) and then wash
  4. washWash the combined organic portions with brine (2×150 ml)
  5. dry with materialdry (MgSO4)
  6. filtrationfilter
  7. concentrationconcentrate in vacuo

Sources & evidence

ORD record
ord-c70c14c550d94a0db353e06a77508379
Source dataset
uspto-grants-2007_07
Patent number
US07250442B2

Reaction notes

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