Phosphorus oxychloride → 3,4-Dihydro-4,4-dimethyl-2H-pyran-2-one

HRID 225026Notes

Reaction equation

HRID 225026 reaction equation
[CH3:1][C:2]([CH3:12])([CH2:9][CH:10]=O)[CH2:3][C:4]([O:6]CC)=[O:5].P(Cl)(Cl)(Cl)=O>S1(CCCC1)(=O)=O>[CH3:12][C:2]1([CH3:1])[CH:9]=[CH:10][O:6][C:4](=[O:5])[CH2:3]1

Participants

4

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 13050815Ethyl 4-formyl-3,3-dimethylbutanoate

Product 1

HCID 30186853,4-Dihydro-4,4-dimethyl-2H-pyran-2-oneYield 77%

Reagents, catalysts & solvents 1

HCID 31347SulfolaneSolvent2×

Conditions

Temperature
200 °C

Procedure

A solution of 16.98 g (0.10 mole at 93% purity) of ethyl 3,3-dimethyl-5-oxopentanoate and 9.44 g (0.062 mole) of phosphoryl chloride in 10 g of sulfolane was added to 250 g of sulfolane and the whole heated to 200° C. in an oil bath during 50 minutes. The reaction mixture was stirred at 200° C. for 1 hour, then subjected to distillation to give 9.71 g of 3,4-dihydro-4,4-dimethyl-2H-pyran-2-one in 2 fractions: fraction 1, 7.49 g, bp 55° C./400 Pa (3 mm Hg), 95.9% purity (glpc); fraction 2, 2.22 g, bp 55°-120° C./400 Pa, 71.1% purity (glpc).

Workup

  1. distillationsubjected to distillation

Sources & evidence

ORD record
ord-43e8137e7f42465fb1ebfb2001a4f9cc
Source dataset
uspto-grants-1980_11
Patent number
US04235780

Reaction notes

Loading…