Process for the preparation of gamma-oxosenecioic acid esters

Claim 2

A COMPOUND OF THE FORMULA

Claim 3

THE PROCESS OF PREPARING A NITRONE WHICH COMPRISES PREPARING A SOLUTION BY DISSOLVING ONE MOLE OF A LOWER ALKYL $-BROMOSENECIOATE IN BENZENE, MIXING ONE MOLE OF ANHYDROUS PYRIDINE WITH THE RESULTING SOLUTION WHILE STIRRING AND COOLING, HEATING THE RESULTANT MIXTURE UNDER REFLUX CONDITIONS UNTIL THE MIXTURE BECOMES RED AND FORMS AN UPPER LAYER AND A LOWE LAYER, COOLING THE MIXTURE, SEPARATELY TREATING THE LOWER LAYER BY ADDING THERETO ONE MOLE OF P-NITROSODIMETHYLANILINE IN AN ALCOHOL SOLUTION UNDER COOLING CONDITIONS, ADDING TO THE ABOVE-TREATED LOWER LAYER A SODIUM HYDROXIDE SOLUTION WHILE STIRRING UNTIL A CRYSTALLINE PRODUCT SEPARATES OUT, AND RECOVERING THE CRYSTALLINE PRODUCT.

Claim 4

THE PROCESS OF PREPARING A NITRONE WHICH COMPRISES PREPARING A SOLUTION BY DISSOLVING ONE MOLE OF A LOWER ALKYL $-BROMOSENECIOATE IN BENZENE, MIXING ONE MOLE OF ANHYDROUS PYRIDINE WITH THE RESULTING SOLUTION WHILE STIRRING AND COOLING, HEATING THE RESULTANT MIXTURE UNDER REFLUX CONDITIONS UNTIL THE MIXTURE BECOMES RED AND FORMS AN UPPER LAYER AND A LOWE LAYER, COOLING THE MIXTURE, SEPARATELY TREATING THE LOWER LAYER BY ADDING THERETO ONE MOLE OF P-NITROSODIMETHYLANILINE IN AN ALCOHOL SOLUTION UNDER COOLING CONDITIONS, ADDING TO THE ABOVE-TREATED LOWER LAYER A SODIUM HYDROXIDE SOLUTION WHILE STIRRING UNTIL A CRYSTALLINE PRODUCT SEPARATES OUT, AND RECOVERING THE CRYSTALLINE PRODUCT.

Claim 5

A PROCESS AS SET FORTH IN CLAIM 2 CINCLUDING THE ADDITIONAL STEPS OF SUSPENDING THE CRYSTALLINE PRODUCT IN ETHER, ADDING TO THE SUSPENSION SULFURIC ACID WHILE STIRRING AND COOLING, REMOVING AN ETHER LAYER FROM THE ACIDIFIED SUSPENSION, AND DISTILLING THE ETHER FROM THE ETHER LAYER TO REMOVE A RESIDUE.