Dimethylformamide → HCID 21426106, compound

HRID 258575Notes

Reaction equation

HRID 258575 reaction equation
[C:1]([CH2:5][C:6]1[N:7]2[CH:13]=[C:12]([C:14]3[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=3)[CH:11]=[C:8]2[S:9][CH:10]=1)([O:3][CH3:4])=[O:2].CN(C)[CH:22]=[O:23].P(Cl)(Cl)(Cl)=O.[OH-].[Na+]>O.C(N(CC)CC)C>[C:1]([CH2:5][C:6]1[N:7]2[C:13]([CH:22]=[O:23])=[C:12]([C:14]3[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=3)[CH:11]=[C:8]2[S:9][CH:10]=1)([O:3][CH3:4])=[O:2]

Participants

7

Reactant 4

HCID 6228Dimethylformamide2×HCID 14798Sodium HydroxideHCID 24813Phosphorus oxychlorideHCID 21426167Methyl (6-phenylpyrrolo[2,1-b][1,3]thiazol-3-yl)acetate

Product 1

HCID 21426106HCID 21426106, compound

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8471TriethylamineSolvent

Conditions

Temperature
-40 °C

Procedure

A solution of 200 mg. of 3-carbomethoxymethyl-6-phenylpyrrolo[2,1-b] thiazole in 2 ml. of dimethylformamide is cooled to -40°, and 500 mg of a 1:2 mixture of phosphorous oxychloride:dimethylformamide is added. The temperature of the reaction is maintained at -40° C. for 30 minutes, then 2 ml of triethylamine are added and the mixture allowed to warm to room temperature. After 2 hours, 2 ml of 10% sodium hydroxide solution are added; the reaction mixture is diluted with water and extracted four times with ether. The combined ether extracts are diluted with hexane and washed with water. After drying and evaporation, the residue is chromatographed on 10 g of silica gel. Elution with chloroform initially gives 3-carbomethoxy-5-phenylthiacycl[2.2.2]azine as a brilliant yellow material, intensely fluorescent under long wavelength ultra-violet light, which may be crystallized from hexane, m.p. 118°-120°. Continued elution with chloroform affords 3-carbomethoxymethyl-5-formyl-6-phenylpyrrolo[2,1-b] thiazole, δ 3.70(3H), 4.42(2H), 6.40(1H), 6.61(1H), 0.93(1H) ppm. 150 Mg. of this aldehyde is refluxed in 100 ml of tetrahydrofuran with 0.5 ml. of triethylamine, 5 mg. of p-toluenesulfonic acid, and 20 ml of pentamethylsilazane to give an additional amount of 3-carbomethoxy-5-phenylthiacyl[2.2.2] azine.

Workup

  1. temperatureto warm to room temperature
  2. extractionextracted four times with ether
  3. additionThe combined ether extracts are diluted with hexane
  4. washwashed with water
  5. customAfter drying
  6. customevaporation
  7. customthe residue is chromatographed on 10 g of silica gel
  8. washElution with chloroform initially gives 3-carbomethoxy-5-phenylthiacycl[2.2.2]azine as a brilliant yellow material
  9. customintensely fluorescent under long wavelength ultra-violet light, which may be crystallized from hexane, m.p. 118°-120°
  10. washContinued elution with chloroform

Sources & evidence

ORD record
ord-43be78056b95483e87f23349f2aecc84
Source dataset
uspto-grants-1977_07
Patent number
US04033978

Reaction notes

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