4-Toluenesulfonyl chloride → HCID 59815649, compound

HRID 2117354Notes

Reaction equation

HRID 2117354 reaction equation
[Br:1][C:2]1[CH:3]=[C:4]([N+:9]([O-:11])=[O:10])[C:5]([OH:8])=[N:6][CH:7]=1.[C:12]1([CH3:22])[CH:17]=[CH:16][C:15]([S:18](Cl)(=[O:20])=[O:19])=[CH:14][CH:13]=1.C(N(CC)CC)C>C(Cl)Cl.CN(C1C=CN=CC=1)C>[CH3:22][C:12]1[CH:17]=[CH:16][C:15]([S:18]([O:8][C:5]2[C:4]([N+:9]([O-:11])=[O:10])=[CH:3][C:2]([Br:1])=[CH:7][N:6]=2)(=[O:20])=[O:19])=[CH:14][CH:13]=1

Participants

6

Reactant 3

HCID 73974-Toluenesulfonyl chlorideHCID 8471TriethylamineHCID 178418997HCID 178418997, compound

Product 1

HCID 59815649HCID 59815649, compound

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6344DichloromethaneSolvent2×

Procedure

5-Bromo-3-nitropyridin-2-ol (30.00 g, 0.137 mmol) and p-toluenesulfonyl chloride (30.03 g, 0.158 mmol) were suspended in CH2Cl2 under N2 and treated dropwise with triethylamine (38.2 mL, 0.274 mmol) prior to the addition of DMAP (3.35 g, 0.027 mmol). After stirring at rt for 16 h the mixture was diluted with CH2Cl2 (500 mL) then washed with 1M HCl(aq) (2×500 mL) and brine (500 mL). The aqueous layer was back-extracted with CH2Cl2 (200 mL) and the combined organic layers dried over Na2SO4, and concentrated in vacuo. The crude material thus isolated was chromatographed over silica gel eluting with 50% EtOAc/hexane to give, on evaporation, a solid which was crystallized from 50% EtOAc/hexane to afford 5-bromo-3-nitropyridin-2-yl 4-methylbenzenesulfonate. 1H NMR (400 MHz, CDCl3) δ 2.51 (s, 3H), 7.43 (dd, 2H, J=8.4, 0.4 Hz), 7.99 (dt, 2H, J=6.8, 2.0 Hz), 8.52 (d, 1H, J=2.4 Hz), 8.60 (d, 1H, J=2.4 Hz).

Workup

  1. washthen washed with 1M HCl(aq) (2×500 mL) and brine (500 mL)
  2. extractionThe aqueous layer was back-extracted with CH2Cl2 (200 mL)
  3. dry with materialthe combined organic layers dried over Na2SO4
  4. concentrationconcentrated in vacuo
  5. customThe crude material thus isolated
  6. customwas chromatographed over silica gel eluting with 50% EtOAc/hexane
  7. customto give, on evaporation
  8. customa solid which was crystallized from 50% EtOAc/hexane

Sources & evidence

ORD record
ord-a70a1687f9e4444c9ea27d30e09190de
Source dataset
uspto-grants-2008_10
Patent number
US07442709B2

Reaction notes

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