Tributylstannane → 4,4-Dimethoxy-1,5-dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-2-one

HRID 502913

Reaction equation

HRID 502913 reaction equation
Cl[CH:2]1[C:8]([O:11][CH3:12])([O:9][CH3:10])[C:7]2([CH3:14])[O:13][C:4]([CH3:15])([CH:5]=[CH:6]2)[C:3]1=[O:16].C(#N)N(C)C.C([SnH](CCCC)CCCC)CCC.CCCCCC.C(OCC)(=O)C>C1(C)C=CC=CC=1>[CH3:10][O:9][C:8]1([O:11][CH3:12])[C:7]2([CH3:14])[O:13][C:4]([CH3:15])([CH:5]=[CH:6]2)[C:3](=[O:16])[CH2:2]1

Participants

6

Reactant 4

HCID 5948TributylstannaneHCID 15112DimethylcyanamideHCID 21226206Ethyl acetate hexaneHCID 586095323-Chloro-4,4-dimethoxy-1,5-dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-2-one

Product 1

HCID 586095264,4-Dimethoxy-1,5-dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-2-one

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

2.2 g (8.92 mmol) of 3-chloro-4,4-dimethoxy-1,5-dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-2-one in 240 ml of toluene are degassed, with heating at reflux temperature, and a catalytic amount of 66 mg of azaisobutyronitrile (AIBN) and a solution of 5.9 ml (22.3 mmol) of tributyltin hydride are added in succession. The reaction mixture is maintained at reflux temperature for a further 20 minutes to complete the reaction (TLC monitoring: hexane/ethyl acetate 4:1). The reaction mixture is then concentrated by evaporation under reduced pressure. The residue is then taken up in acetonitrile and the tin-containing residues are extracted by means of hexane. The acetonitrile phase is concentrated by evaporation in vacuo, 1.56 g (82.4% of theory) of 4,4-dimethoxy-1,5-dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-2-one remaining behind in the form of a yellow oil, which can be used for the next reaction step without further purification.

Workup

  1. temperaturewith heating
  2. temperatureat reflux temperature
  3. temperatureThe reaction mixture is maintained
  4. temperatureat reflux temperature for a further 20 minutes
  5. concentrationThe reaction mixture is then concentrated by evaporation under reduced pressure
  6. additionthe tin-containing residues
  7. extractionare extracted by means of hexane
  8. concentrationThe acetonitrile phase is concentrated by evaporation in vacuo, 1.56 g (82.4% of theory) of 4,4-dimethoxy-1,5-dimethyl-8-oxa-bicyclo[3.2.1]oct-6-en-2-one remaining behind in the form of a yellow oil, which
  9. customcan be used for the next reaction step without further purification

Sources & evidence

ORD record
ord-52d72131b20f41438718e4846a29e751
Source dataset
uspto-grants-2010_08
Patent number
US07776888B2

Linked notes

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