Acetone → Diethyl isopropylidenemalonate

HRID 362849Notes

Reaction equation

HRID 362849 reaction equation
[CH3:1][C:2]([CH3:4])=O.[C:5]([O:13][CH2:14][CH3:15])(=[O:12])[CH2:6][C:7]([O:9][CH2:10][CH3:11])=[O:8].C(OC(=O)C)(=O)C>ClCCl.[Cl-].[Zn+2].[Cl-]>[C:2](=[C:6]([C:7]([O:9][CH2:10][CH3:11])=[O:8])[C:5]([O:13][CH2:14][CH3:15])=[O:12])([CH3:4])[CH3:1]

Participants

6

Reactant 3

HCID 180AcetoneHCID 7761Diethyl MalonateHCID 7918Acetic Anhydride

Product 1

HCID 81255Diethyl isopropylidenemalonateYield 32.3%

Reagents, catalysts & solvents 2

HCID 3007855ZincchlorideCatalystHCID 6344DichloromethaneSolvent

Conditions

Temperature
90 °C

Procedure

Diethyl isopropylidenemalonate was prepared according to the procedure of E. L. Eliel, R. O. Hutchins, and Sr. M. Knoeber, Organic Synthesis Coll. Vol. VI, 442, 1988, with following modifications. A mixture of acetone (54 g, 0.93 mol, Mallinckrodt), diethyl malonate (100 g, 0.62 mol, Aldrich), acetic anhydride (80 g, 0.78 mol, Mallinckrodt), and zinc chloride (12.5 g, 0.78 mol, Aldrich) was refluxed (90° C. oil bath) for 18 h while protected from moisture. The reaction solution was diluted with dichloromethane (500 ml) and washed with cold water (3×50 ml). The aqueous washes were combined and extracted with dichloromethane. All dichloromethane layers were combined and concentrated by spin evaporation in vacuo. The residual oil was distilled under vacuum and the fractions boiling at 102°-138° C. at 12 Torr were combined with the pot residue and heated for 6 h with a 200° C. oil bath. The dark oil was redistilled to give 40.1 g (32%) of diethyl isopropylidenemalonate as a clear oil: b.p., 110°-115° C./12 mmHg;

Workup

  1. customDiethyl isopropylidenemalonate was prepared
  2. customKnoeber, Organic Synthesis Coll
  3. washwashed with cold water (3×50 ml)
  4. extractionextracted with dichloromethane
  5. concentrationconcentrated by spin evaporation in vacuo
  6. distillationThe residual oil was distilled under vacuum
  7. temperatureheated for 6 h with a 200° C. oil bath
  8. distillationThe dark oil was redistilled

Sources & evidence

ORD record
ord-0dda62ee4c624272ba1094f0e6f9a2fd
Source dataset
uspto-grants-1999_02
Patent number
US05872118

Reaction notes

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