Methylenecyclobutane → Ethyl 5-oxa-6-azaspiro[3.4]oct-6-ene-7-carboxylate

HRID 79977Notes

Reaction equation

HRID 79977 reaction equation
[CH2:1]=[C:2]1[CH2:5][CH2:4][CH2:3]1.Cl/[C:7](=[N:13]\[OH:14])/[C:8]([O:10][CH2:11][CH3:12])=[O:9].C(=O)(O)[O-].[Na+]>C(OCC)(=O)C>[CH2:11]([O:10][C:8]([C:7]1[CH2:1][C:2]2([CH2:5][CH2:4][CH2:3]2)[O:14][N:13]=1)=[O:9])[CH3:12]

Participants

5

Reactant 3

HCID 14262MethylenecyclobutaneHCID 516892Sodium Bicarbonate2×HCID 95760052-Chloro-2-hydroxyiminoacetic acid ethyl ester2×

Product 1

HCID 59611573Ethyl 5-oxa-6-azaspiro[3.4]oct-6-ene-7-carboxylate

Reagents, catalysts & solvents 1

HCID 8857Ethyl AcetateSolvent2×

Procedure

To a solution of methylenecyclobutane (2 mL, 21.6 mmol) in ethyl acetate (125 mL) was added (Z)-ethyl 2-chloro-2-(hydroxyimino)acetate (6.55 g, 43.2 mmol) and solid sodium bicarbonate (16.3 g, 194 mmol). The reaction mixture was sealed and stirred at room temperature for 6 hours. More (Z)-ethyl 2-chloro-2-(hydroxyimino)acetate (4 g, 26.4 mmol) and sodium bicarbonate (8 g, 95.2 mmol) were added and the reaction was stirred at room temperature for an additional 12 hours. The reaction was diluted with ethyl acetate and washed successively with water and brine, dried (MgSO4) and concentrated to yield crude 5-oxa-6-aza-spiro[3.4]oct-6-ene-7-carboxylic acid ethyl ester, contaminated with (Z)-Ethyl 2-chloro-2-(hydroxyimino)acetate and related compounds.

Workup

  1. customThe reaction mixture was sealed
  2. stirringthe reaction was stirred at room temperature for an additional 12 hours
  3. washwashed successively with water and brine
  4. dry with materialdried (MgSO4)
  5. concentrationconcentrated

Sources & evidence

ORD record
ord-88103addde0a451c9c8c8fb085afe958
Source dataset
uspto-grants-2014_09
Patent number
US08841278B2

Reaction notes

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