Triethylamine → Pentyl 2-chloro-5-[(6-methyl-2,3-dihydro-1,4-oxathiine-5-carbonyl)amino]benzoate

HRID 326336Notes

Reaction equation

HRID 326336 reaction equation
S(Cl)(Cl)=O.[CH3:5][C:6]1[O:7][CH2:8][CH2:9][S:10][C:11]=1[C:12]([OH:14])=O.[NH2:15][C:16]1[CH:17]=[CH:18][C:19]([Cl:30])=[C:20]([CH:29]=1)[C:21]([O:23][CH2:24][CH2:25][CH2:26][CH2:27][CH3:28])=[O:22].C(N(CC)CC)C>C(Cl)Cl.C(O)C>[Cl:30][C:19]1[CH:18]=[CH:17][C:16]([NH:15][C:12]([C:11]2[S:10][CH2:9][CH2:8][O:7][C:6]=2[CH3:5])=[O:14])=[CH:29][C:20]=1[C:21]([O:23][CH2:24][CH2:25][CH2:26][CH2:27][CH3:28])=[O:22]

Participants

7

Reactant 4

HCID 8471TriethylamineHCID 24386Thionyl ChlorideHCID 5399462-Methyl-5,6-dihydro-1,4-oxathiine-3-carboxylic acidHCID 21470243Pentyl 5-amino-2-chlorobenzoate

Product 1

HCID 465812Pentyl 2-chloro-5-[(6-methyl-2,3-dihydro-1,4-oxathiine-5-carbonyl)amino]benzoateYield 48%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 6344DichloromethaneSolvent2×

Procedure

Thionyl chloride (3.9 g, 0.033 mole) was added to a stirred mixture of 5,6-dihydro-2-methyl-1,4-oxathiin-3-carboxylic acid (5.2 g, 0.032 mole) and methylene chloride (100 ml). The mixture was stirred overnight at room temperature, then evaporated under reduced pressure. The residue, crude 5,6-dihydro-2-methyl-1,4-oxathiin-3-carbonyl chloride, was dissolved in methylene chloride (100 ml), and the ice-chilled solution treated dropwise with a solution of pentyl 5-amino-2-chlorobenzoate (7.9 g, 0.033 mole) and triethylamine (3.3 g, 0.033 mole) in methylene chloride (100 ml). The reaction mixture was stirred at room temperature for 4 hours, then worked up by washing in sequence with water, dilute hydrochloric acid, water, 2% sodium hydroxide and water. Evaporation of the solvent left an oil, which solidified very slowly. After recrystallization from ethanol (30 ml) the product 5.9 g, 47% yield) melted at 65°-68° C. A second recrystallization raised the melting point to 70°-71° C.

Workup

  1. customevaporated under reduced pressure
  2. dissolutionThe residue, crude 5,6-dihydro-2-methyl-1,4-oxathiin-3-carbonyl chloride, was dissolved in methylene chloride (100 ml)
  3. temperaturethe ice-chilled solution
  4. stirringThe reaction mixture was stirred at room temperature for 4 hours
  5. washby washing in sequence with water, dilute hydrochloric acid, water, 2% sodium hydroxide and water
  6. customEvaporation of the solvent
  7. waitleft an oil, which

Sources & evidence

ORD record
ord-aed229050219424dbe4e19f636d77c7d
Source dataset
uspto-grants-1993_12
Patent number
US05268389

Reaction notes

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