Propanal → 5-Ethyl-4-tosyl-2-oxazoline

HRID 505573Notes

Reaction equation

HRID 505573 reaction equation
[S:1]([CH2:11][N:12]=[C:13]=[O:14])([C:4]1[CH:10]=[CH:9][C:7]([CH3:8])=[CH:6][CH:5]=1)(=[O:3])=[O:2].[CH:15](=O)[CH2:16][CH3:17].[Na].O1CCN=C1>C(O)C>[CH2:16]([CH:17]1[O:14][CH:13]=[N:12][CH:11]1[S:1]([C:4]1[CH:5]=[CH:6][C:7]([CH3:8])=[CH:9][CH:10]=1)(=[O:3])=[O:2])[CH3:15]

Participants

6

Reactant 4

HCID 527PropanalHCID 68157OxazolineHCID 5360545SodiumHCID 117890781-Isocyanatomethanesulfonyl-4-methylbenzene

Product 1

HCID 667581855-Ethyl-4-tosyl-2-oxazolineYield 81%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

To a stirred suspension of tosylmethylisocyanate (TosMIC, 3.90 g, 20 mmol) and propionaldehyde (1.5 mL 20.4 mmol) in 60 mL dry ethanol, finely powdered sodium cyamide (0.098 g, 2 mmol) was added. The reaction mixture became clear and white crystals of oxazoline began to precipitate in 15 min. The reaction was continuously stirred for an additional 30 min. The mixture was filtered and the crystals were washed with ether-hexane (1:1) before drying. Compound 15 was attained in 81% yield (4.1 g). The structure was confirmed by 1H NMR in CDCl3, LC-MS: [M+1]=254. Purity was >98%.

Workup

  1. additionwas added
  2. customto precipitate in 15 min
  3. filtrationThe mixture was filtered
  4. washthe crystals were washed with ether-hexane (1:1)
  5. custombefore drying

Sources & evidence

ORD record
ord-97d179396b0740fb8856b9230ba3e5e7
Source dataset
uspto-grants-2010_08
Patent number
US07781442B2

Reaction notes

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