Back to results
US 5,300,654 AGranted
Method for the preparation of unsaturated ketones
AssigneeNippon Soda Co., Ltd.
InventorsMasashi Nakajima, Tadashi Kyotani, Mikio Sawaki
Life of this patent
Estimating the term…
Abstract
.beta.-hydroxyketones are prepared by reacting an aldehyde with acetone in the presence of perhydroisoindole or pyrrolidine and water. The resulting .beta.-hydroxyketone is further reacted in the presence of a solvent mixture to produce .alpha.-.beta.-unsaturated ketones.
Claims3
Method for preparing .alpha.,.beta.-unsaturated ketone which comprises:
- (1) dehydrating a .beta.-hydroxyketone of the formula (I) ##STR52## wherein R is (i) an aliphatic group having a side chain at the 1 position, (ii) an alicyclic group optionally substituted, (iii) a heterocyclic group optionally substituted;
- or (iv) a phenyl group optionally substituted;
- (2) in the presence of an acid catalyst in a solvent mixture comprising water and a water-insoluble organic solvent compound
- (3) under conditions sufficient to thereby produce a .alpha.,.beta.-unsaturated ketone of the formula (II) ##STR53## wherein R is as defined above.
1 more element
Method for preparing .alpha.,.beta.-unsaturated ketone which comprises:
- (1) reacting an aldehyde of the formula (III)
- RCHO (III)
- wherein R is (i) an aliphatic group having a side chain at the 1 position, (ii) an alicyclic group optionally substituted, (iii) a heterocyclic group optionally substituted, or (iv) a phenyl group optionally substituted;
- (2) with acetone,
- (3) utilizing a catalyst comprising perhydroisoindole or pyrrolidine or mixtures thereof,
- (4) in the presence of water,
- (5) under condensation conditions sufficient to thereby produce a .beta.-hydroxyketone of the formula (I) ##STR54## wherein R is as defined above, and to remove unreacted acetone therefrom;
- (6) dehydrating the .beta.-hydroxyketone
- (7) utilizing an acid catalyst in a solvent mixture comprising water and a water-insoluble organic solvent compound,
- (8) under conditions sufficient to thereby produce .alpha.,.beta.-unsaturated ketone of the formula (II) ##STR55## wherein R is as defined above.
7 more elements
Method of producing .alpha.,.beta.-unsaturated ketone which comprises
- (a) admixing acetone and a catalyst comprising perhydroisoindole or pyrrolidine of the formula ##STR56## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are hydrogen or lower aliphatic groups in an aqueous solvent;
- (b) slowly introducing into the acetone-catalyst admixture an aldehyde of the formula
- RCHO
- wherein R is an aliphatic group having a side chain at the 1 position, an alicyclic group optionally substituted, a heterocyclic group optionally substituted, or a phenyl group optionally substituted, under condensation conditions sufficient to react the acetone and aldehyde thereby producing an aqueous solution of corresponding .beta.-hydroxyketone reaction product;
- (c) removing unreacted acetone from the solution of reaction product;
- (d) introducing an acid catalyst and a water insoluble organic solvent into the aqueous reaction product under reaction conditions to convert .beta.-hydroxyketone into the corresponding .alpha.,.beta.-unsaturated ketone of the formula ##STR57## wherein R is as defined above;
- and, (e) recovering .alpha.,.beta.-unsaturated ketone in high purity.
4 more elements
Dependencies are inferred from the claim text.