Acetic Acid → HCID 20382824, compound

HRID 1447757Notes

Reaction equation

HRID 1447757 reaction equation
[C:1]([O:5][C:6]([N:8]1[CH:12]([C:13]([O:15][CH2:16][CH3:17])=[O:14])[C:11]2([CH2:22][S:21][CH2:20][S:19][CH2:18]2)OC1=S)=[O:7])([CH3:4])([CH3:3])[CH3:2].C(O)(=O)C>O1CCCC1>[C:1]([O:5][C:6]([NH:8][C:12](=[C:11]1[CH2:22][S:21][CH2:20][S:19][CH2:18]1)[C:13]([O:15][CH2:16][CH3:17])=[O:14])=[O:7])([CH3:2])([CH3:3])[CH3:4]

Participants

4

Reactant 2

HCID 176Acetic AcidHCID 20382826HCID 20382826, compound

Product 1

HCID 20382824HCID 20382824, compoundYield 70%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
20 °C

Procedure

A solution of potassium tert.-butylate (5.35 g) in tetrahydrofurane (40 cc) is cooled to -70° C. A solution of 3-tert.-butoxycarbonyl-4-ethoxycarbonyl-2-thioxo-1-oxa-7,9-dithia-3-azaspiro[4.5]decane (9 g) in tetrahydrofurane (40 cc) is added dropwise. The mixture is stirred for a further 3 hours, acetic acid (2.9 g) is then added and the reaction mixture is allowed to warm up to 20° C. The tetrahydrofurane is evaporated off under reduced pressure (20 mm Hg) at 30° C. The residue is dissolved in ethyl acetate (25 cc). The solution is washed with water (25 cc) and then dried over sodium sulphate. The solution is filtered and the filtrate is concentrated to dryness under reduced pressure (20 mm Hg). A solid residue is obtained and treated with petroleum ether (100 cc). The precipitate is filtered off and dried under reduced pressure. Ethyl α-tert.-butoxycarbonylamino-(4,5-dihydro-1,3-dithiin-5-ylidene)-acetate (5.3 g) is thus obtained in the form of a beige solid which melts at 154° C. (Kofler instantaneous m.p.).

Workup

  1. customThe tetrahydrofurane is evaporated off under reduced pressure (20 mm Hg) at 30° C
  2. dissolutionThe residue is dissolved in ethyl acetate (25 cc)
  3. washThe solution is washed with water (25 cc)
  4. dry with materialdried over sodium sulphate
  5. filtrationThe solution is filtered
  6. concentrationthe filtrate is concentrated to dryness under reduced pressure (20 mm Hg)
  7. customA solid residue is obtained
  8. filtrationThe precipitate is filtered off
  9. customdried under reduced pressure

Sources & evidence

ORD record
ord-72161b0086d045ab8012ec64c293eacc
Source dataset
uspto-grants-1979_12
Patent number
US04178290

Reaction notes

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