Phosphorus oxychloride → 4-(2-chloro-4-thiazolyl)Pyridine

HRID 2309799

Reaction equation

HRID 2309799 reaction equation
O[C:2]1[S:3][CH:4]=[C:5]([C:7]2[CH:12]=[CH:11][N:10]=[CH:9][CH:8]=2)[N:6]=1.P(Cl)(Cl)([Cl:15])=O>>[Cl:15][C:2]1[S:3][CH:4]=[C:5]([C:7]2[CH:12]=[CH:11][N:10]=[CH:9][CH:8]=2)[N:6]=1

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 178418513HCID 178418513, compound

Product 1

HCID 140969694-(2-chloro-4-thiazolyl)PyridineYield 29%

Conditions

Temperature
140 °C

Procedure

A mixture of 2-hydroxy-4-(4-pyridyl)thiazole (17.8 g, 0.10 mol) in phosphorous oxychloride (175 mL) was heated at 140° C. for 48 hours then quenched by carefully pouring onto ice (4000 mL). The resulting mixture was basified with 50% sodium hydroxide to pH 9 and extracted with methylene chloride (5×400 mL). The combined extracts were dried over sodium sulfate, concentrated, and chromatographed over silica gel (ethyl acetate as eluant). Recrystallization from ethyl acetate/hexane afforded 2-chloro-4-(4-pyridyl)thiazole (5.70 g, 29%). mp. 124°-125° C.

Workup

  1. customthen quenched
  2. additionby carefully pouring onto ice (4000 mL)
  3. extractionextracted with methylene chloride (5×400 mL)
  4. dry with materialThe combined extracts were dried over sodium sulfate
  5. concentrationconcentrated
  6. customchromatographed over silica gel (ethyl acetate as eluant)
  7. customRecrystallization from ethyl acetate/hexane

Sources & evidence

ORD record
ord-1be53a5e882e4db38cac8eb9b00d8508
Source dataset
uspto-grants-1987_09
Patent number
US04697012

Linked notes

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