2-Diazonio-1-[(3-methylbut-2-en-1-yl)oxy]ethen-1-olate → 6,6-Dimethyl-3-oxabicyclo[3.1.0]hexan-2-one

HRID 370570Notes

Reaction equation

HRID 370570 reaction equation
[N+](=[CH:3][C:4]([O:6][CH2:7][CH:8]=[C:9]([CH3:11])[CH3:10])=[O:5])=[N-]>O1CCOCC1.[Cu]>[CH3:10][C:9]1([CH3:11])[CH:3]2[CH:8]1[CH2:7][O:6][C:4]2=[O:5]

Participants

4

Reactant 1

HCID 544938542-Diazonio-1-[(3-methylbut-2-en-1-yl)oxy]ethen-1-olate

Product 1

HCID 118153586,6-Dimethyl-3-oxabicyclo[3.1.0]hexan-2-one

Reagents, catalysts & solvents 2

HCID 23978CopperCatalystHCID 312751,4-DioxaneSolvent2×

Procedure

A solution of 3-methyl-2-butenyl diazoacetate (980 mg, 6.4 mmoles) in dioxane (15 ml) was added dropwise to a solution of bis[2-butoxy-α-[2-butoxy-5-(1,1-dimethylethyl)phenyl]-5-(1,1-dimethylethyl)-α-[(S)-1-[[2-hydroxyphenyl)methylene]amino]ethyl]benzenemethanolato (2-)]-copper (83 mg, 0.064 mmole) in dioxane (55 ml) at 110°. When the evolution of nitrogen started, the temperature was slowly lowered to 52°-3°. The addition took 5.5 hours, and the evolution of almost theoretical amounts of nitrogen was observed. After the addition was completed, the reaction mixture was stirred at 52°-3° for 2 hours, evaporated to dryness, and distilled under vacuum to afford 6,6-dimethyl-2-oxo-3-oxabicyclo[3.1.0]hexane enriched with the (1R,5S) isomer (500 mg). The optical rotation of the product was [α]D29 =-53.5° (CHCl3).

Workup

  1. customwas slowly lowered to 52°-3°
  2. additionThe addition
  3. additionAfter the addition
  4. customevaporated to dryness
  5. distillationdistilled under vacuum

Sources & evidence

ORD record
ord-9656fbaa4ca84cdda76f24773bb40915
Source dataset
uspto-grants-1985_07
Patent number
US04526987

Reaction notes

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