Preparation of 2-phenylsemicarbazides
AssigneeShell Oil Company
InventorKurt H. G. Pilgram
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Abstract
2-Phenylsemicarbazides are prepared by a multi-step process involving: (a) treating a phenylhydrazine, or salt thereof, with a chloroformate; (b) adding phosgene; (c) treating the resulting product with an amine; and (d) hydrolyzing the resulting acylated semicarbazide. The reaction can proceed through a .DELTA..sup.2 -1,3,4-oxadiazolin-5-one intermediate formed with heating in step (b). Certain of the products are novel compounds.
Claims15
A process for the preparation of a 2-phenylsemicarbazide which comprises the steps of
- (a) treating a phenylhydrazine, or salt thereof, with a chloroformate;
- (b) adding phosgene;
- (c) treating the resulting product with a secondary amine;
- and
- (d) hydrolyzing the resulting acylated semicarbazide product from (c) to a 2-phenylsemicarbazide.
A process for the preparation of a 2-phenylsemicarbazide which comprises treating a 4-phenyl-2-substituted-.DELTA..sup.2 -1,3,4-oxadiazolin-5-one with a secondary amine HNR.sup.1 R.sup.2 wherein R.sup.1 and R.sup.2 are hydrogen, alkyl or alkylene optionally interrupted by one or more oxygen atoms and hydrolyzing the resulting reaction product in the presence of an alkaline material to produce the desired 2-phenylsemicarbazide.
Dependencies are inferred from the claim text.