5-(2-Methyl-1,3-dioxolan-2-yl)-2-pentanone → HCID 10975921, compound

HRID 1448932Notes

Reaction equation

HRID 1448932 reaction equation
[CH2:1]([Li])CCC.[CH2:6]1[CH2:17][O:16][C:8]([CH3:15])([CH2:9][CH2:10][CH2:11][C:12](=O)[CH3:13])[O:7]1>[Br-].C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.O1CCCC1>[CH2:6]1[CH2:17][O:16][C:8]([CH3:15])([CH2:9][CH2:10][CH2:11][C:12]([CH3:1])=[CH2:13])[O:7]1

Participants

5

Reactant 2

HCID 104196285-(2-Methyl-1,3-dioxolan-2-yl)-2-pentanoneHCID 178418339Butyllithium2×

Product 1

HCID 10975921HCID 10975921, compoundYield 38%

Reagents, catalysts & solvents 2

HCID 74505Methyltriphenyliphosphonium bromideCatalystHCID 8028TetrahydrofuranSolvent2×

Procedure

To a slurry of methyl triphenylphosphonium bromide (218 g) in anhydrous tetrahydrofuran (1.8 l) cooled to 0° C. is added 1.6 M n-butyllithium (270 ml) and2.6 M n-butyl lithium (37.5 ml). After stirring for 1 hour, 6,6-ethylenedioxy-heptane-2-one (91.3 g) in anhydrous tetrahydrofuran (200 ml) is added dropwise and the mixture stirred for 1.5 hours at room temperature. The reaction mixtures is then filtered and the filter cake washed with ether. The solent is removed via distillation at atmospheric pressure. The crude residue is purified via vacuum distillation to give 6,6-ethylenedioxy-2-methyl-hept-1-ene (33.95 g, 38%) bp 75°@15 mm; nmr (CDCl3,δ), 1.32 (s, 3H, ##STR53## 1.7 (s, 3H, CH3 --C=), 3.92 (s, 4H, OCH2CH2O), 4.67 (bs, 2H, ##STR54##

Workup

  1. stirringthe mixture stirred for 1.5 hours at room temperature
  2. customThe reaction mixtures
  3. filtrationis then filtered
  4. washthe filter cake washed with ether
  5. customThe solent is removed via distillation at atmospheric pressure
  6. distillationThe crude residue is purified via vacuum distillation

Sources & evidence

ORD record
ord-fff14a60ac2b4f029d54e6f37f12469c
Source dataset
uspto-grants-1980_02
Patent number
US04188328

Reaction notes

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