Lithium Hexamethyldisilazide → 5-(Pyridine-2-sulfanyl)-thiazolidine-2,4-dione

HRID 1899876Notes

Reaction equation

HRID 1899876 reaction equation
Br[CH:2]1[S:6][C:5](=[O:7])[NH:4][C:3]1=[O:8].[SH:9][C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][N:11]=1.C[Si]([N-][Si](C)(C)C)(C)C.[Li+]>C1COCC1>[CH:14]1[CH:15]=[C:10]([S:9][CH:2]2[S:6][C:5](=[O:7])[NH:4][C:3]2=[O:8])[N:11]=[CH:12][CH:13]=1

Participants

5

Reactant 3

HCID 2733832Lithium HexamethyldisilazideHCID 34937495-Bromothiazolidine-2,4-dioneHCID 178418616HCID 178418616, compound

Product 1

HCID 105134355-(Pyridine-2-sulfanyl)-thiazolidine-2,4-dioneYield 93.5%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a solution of 5-bromo-thiazolidine-2,4-dione (28.24 g, 0.144 mol) and 2-mercaptopyridine [(II), 16.0 g, 0.144 moll] in dry THF (200 mL) at -78° C. was added lithium bis(trimethylsilyl)amide (1.0M in hexanes, 317 mL, 0.317 mol) dropwise over a 40 min period. After 30 min. the reaction mixture was warmed to room temperature. After an additional 3 hr, 10% HC1 was added to pH=1. The layers were separated and the aqueous phase was extracted with ethyl acetate (2×500 mL). The combined organic phase was washed with water (500 mL), brine (500 mL), dried (MgSO4) and concentrated to provide the title compound as a green solid (30.45 g, 93%): mp 118°-120 ° C.; NMR (DMSO, d 6): δ 12.35 (s, 1H, NH), 8.39 (d, J=5.3 Hz, 1H, PyrH), 7.69 (dd, J=7.3, 8.3 Hz, 1H, PryH), 7.42 (d, J=8.3 Hz, 1H, PyrH), 7.19 (dd, J=5.3,7.3 Hz, 1H, PyrH), 6.31 (s, 1H, CH), MS(EI): 226 (MI, 12%), 155 (10%), 79 (100%); Anal. (C8H6N2O2S2): C,H,N.

Workup

  1. addition10% HC1 was added to pH=1
  2. customThe layers were separated
  3. extractionthe aqueous phase was extracted with ethyl acetate (2×500 mL)
  4. washThe combined organic phase was washed with water (500 mL), brine (500 mL)
  5. dry with materialdried (MgSO4)
  6. concentrationconcentrated

Sources & evidence

ORD record
ord-4ad4b707d19249d19b7757e72cafdd94
Source dataset
uspto-grants-1996_11
Patent number
US05574051

Reaction notes

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