Acetone → 8-Methylidene-1,4-dioxaspiro[4.5]decane

HRID 132103Notes

Reaction equation

HRID 132103 reaction equation
[CH2:1]([Li])[CH2:2][CH2:3][CH3:4].[O:6]1[C:10]2(CCC(=O)[CH2:12][CH2:11]2)[O:9][CH2:8][CH2:7]1.CC(C)=O>[Br-].C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.O1CCCC1>[C:10]([O-:9])(=[O:6])[CH3:11].[CH2:4]=[C:3]1[CH2:12][CH2:11][C:10]2([O:9][CH2:8][CH2:7][O:6]2)[CH2:1][CH2:2]1

Participants

7

Reactant 3

HCID 180AcetoneHCID 5674151,4-Dioxaspiro[4.5]decan-8-oneHCID 178418339Butyllithium

Product 2

HCID 175AcetateHCID 109537438-Methylidene-1,4-dioxaspiro[4.5]decaneYield 79%

Reagents, catalysts & solvents 2

HCID 74505Methyltriphenyliphosphonium bromideCatalystHCID 8028TetrahydrofuranSolvent

Procedure

A solution of 1.6 M n-butyllithium in hexanes (46 mL, 73.6 mmol) was slowly added to a heterogeneous mixture of methyltriphenylphosphonium bromide (28.07 g, 78.6 mmol) in tetrahydrofuran (150 mL) at −10° C. After stirring for 1 h, 1,4-dioxa-spiro[4.5]decan-8-one (8.01 g, 51.3 mmol) was added. After stirring for 3 h, during which time the solution warmed to ambient temperature, acetone was added and the heterogeneous mixture was concentrated. The residue was diluted with 1:1 methylene chloride:ethyl ether, filtered and concentrated. The residue was flash chromatographed with 49:1, 24:1, and 23:2 hexanes:etheyl acetate as the eluant to yield 6.22 g (79% yield) of 8-methylene-1,4-dioxa-spiro[4.5]decane as a yellow oil.

Workup

  1. stirringAfter stirring for 3 h, during which time the solution
  2. concentrationthe heterogeneous mixture was concentrated
  3. additionThe residue was diluted with 1:1 methylene chloride
  4. filtrationethyl ether, filtered
  5. concentrationconcentrated
  6. customchromatographed with 49:1, 24:1, and 23:2 hexanes

Sources & evidence

ORD record
ord-a660afa0e0f04dca99f02afe9265631c
Source dataset
uspto-grants-2008_06
Patent number
US07385085B2

Reaction notes

Loading…