Process for the preparation of 1,1,1-trifluoro-2-aminoalkanes
AssigneeAmerican Cyanamid Company
InventorsHans-Peter Niedermann, Dieter Gutheil
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Abstract
An improved process for the preparation of a 1,1,1-trifluoro-2-aminoalkane of formula I wherein R1 represents an optionally substituted alkyl group; which comprises hydrogenating the corresponding oxime of formula II wherein R1 has the meaning given above and the winding line indicates that the hydroxy group may be in the (E)- or (Z)-position with respect to the trifluoromethyl group, in the presence of Raney nickel and a diluent; the improvement wherein is, that said reaction is carried out in a diluent selected from an alkanol, a cyclic ether and an aromatic hydrocarbon.
Claims12
In a process for the preparation of a 1,1,1-trifluoro-2-aminoalkane of formula I
- wherein
- R1 represents an optionally substituted alkyl group;
- which comprises hydrogenating the corresponding oxime of formula II
- wherein R1 has the meaning given above and the winding line indicates that the hydroxy group may be in the (E)- or (Z)-position with respect to the trifluoromethyl group, in the presence of Raney nickel in a diluent;
- wherein the improvement is, that the reaction is carried out in a diluent selected from an alkanol, a cyclic ether and an aromatic hydrocarbon and with the proviso that the 1,1,1-trifluoro-2-aminoalkane is obtained at a yield of greater than thirty percent.
In a process for the preparation of a 1,1,1-trifluoro-2-aminoalkane of formula I
- wherein
- R1 represents an optionally substituted alkyl group;
- which comprises hydrogenating the corresponding oxime of formula II
- wherein R1 has the meaning given above and the winding line indicates that the hydroxy group may be in the (E)- or (Z)-position with respect to the trifluoromethyl group, in the presence of Raney nickel in moist form and a diluent;
- wherein the improvement is, that the reaction is carried out in a diluent selected from an alkanol, a cyclic ether and an aromatic hydrocarbon.
In a process for the preparation of a 1,1,1-trifluoro-2-aminoalkane of formula I
- wherein
- R1 represents an optionally substituted alkyl group;
- which comprises hydrogenating the corresponding oxime of formula II
- wherein R1 has the meaning given above and the winding line indicates that the hydroxy group may be in the (E)- or (Z)-position with respect to the trifluoromethyl group, in the presence of Raney nickel and a diluent;
- wherein the improvement is, that the reaction is carried out in a diluent selected from an alkanol, a cyclic ether and an aromatic hydrocarbon, and the mixture consisting of the oxime of formula II, the diluent and Raney nickel is kept under a hydrogen atmosphere at temperatures between 50° C. and 150° C.
In a process for the preparation of a 1,1,1-trifluoro-2-aminoalkane of formula I
- wherein
- R1 represents a C1-4 alkyl group optionally substituted by one or more halogen atoms or an alkoxycarbonyl group;
- which comprises hydrogenating the corresponding oxime of formula II
- wherein R1 has the meaning given above and the winding line indicates that the hydroxy group may be in the (E)- or (Z)-position with respect to the trifluoromethyl group, in the presence of Raney nickel and a diluent;
- wherein the improvement is, that the reaction is carried out in a diluent selected from an alkanol, a cyclic ether and an aromatic hydrocarbon.
Dependencies are inferred from the claim text.