Trichloroacetyl chloride → 1,1-Dichloro-7-oxaspiro[3,5]nonan-2-one

HRID 1853072Notes

Reaction equation

HRID 1853072 reaction equation
[Cl:1][C:2]([Cl:7])(Cl)[C:3](Cl)=[O:4].[CH2:8]=[C:9]1[CH2:14][CH2:13][O:12][CH2:11][CH2:10]1>CCOCC.[Zn]>[Cl:1][C:2]1([Cl:7])[C:9]2([CH2:14][CH2:13][O:12][CH2:11][CH2:10]2)[CH2:8][C:3]1=[O:4]

Participants

5

Reactant 2

HCID 6420Trichloroacetyl chlorideHCID 5489754-Methylideneoxane

Product 1

HCID 866853361,1-Dichloro-7-oxaspiro[3,5]nonan-2-one

Reagents, catalysts & solvents 2

HCID 23994ZincCatalystHCID 3283Diethyl EtherSolvent2×

Procedure

Zinc was activated according to a published procedure (Synthesis 1971; 415). Hydrated copper sulfate (14 g) was dissolved in water (150 mL) and added to zinc dust (60 g). The mixture was stirred for 2 hours under nitrogen. The activated zinc was isolated by filtration, washed with acetone and dried in a vacuum oven at 100° C. prior to use. The solution of 4-methylenetetrahydro-2H-pyran from Step A was dried with sodium sulfate and magnesium sulfate and filtered through Celite® (washing the cake with ether). This removed some orange solids which had precipitated. A solution of trichloroacetyl chloride (5.00 g; 27.5 mmol) in dry ether (250 mL) was added slowly (over 4 hours) to a stirred refluxing mixture of the 4-methylenetetrahydro-2H-pyran in dry ether (250 mL) and the activated zinc (5.00 g; 76.5 mmol) under nitrogen. The mixture was stirred for 16 hours at reflux. The solution was filtered through Celite® and concentrated under reduced pressure. The material was purified by chromatography on silica gel, eluting with 10:1 hexane/ethyl acetate to give impure product (160 mg) as a colorless oil which was continued directly on to the next step.

Workup

  1. washwashed with acetone
  2. customdried in a vacuum oven at 100° C.
  3. dry with materialThe solution of 4-methylenetetrahydro-2H-pyran from Step A was dried with sodium sulfate and magnesium sulfate
  4. filtrationfiltered through Celite® (
  5. washwashing the cake with ether)
  6. customThis removed some orange solids which
  7. customhad precipitated
  8. temperaturerefluxing
  9. temperatureat reflux
  10. filtrationThe solution was filtered through Celite®
  11. concentrationconcentrated under reduced pressure
  12. customThe material was purified by chromatography on silica gel
  13. washeluting with 10:1 hexane/ethyl acetate

Sources & evidence

ORD record
ord-7e8e4de96bd84aca943b13d2e97abfd5
Source dataset
uspto-grants-2015_02
Patent number
US08962596B2

Reaction notes

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