Abstract: The present invention provides a novel process for producing an N-substituted aziridine compound by subjecting an N-substituted alkanolamine to a gas-phase catalytic dehydration reaction (the following reaction formula). ##STR1## In the above formula, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently one member of selected from a hydrogen atom and alkyl groups of 1-4 carbon atoms, and X is one member selected from alkyl groups of 1-4 carbon atoms, a cyclohexyl group, a phenyl group, a benzyl group, hydroxyalkyl groups of 1-4 carbon atoms and aminoalkyl groups of 1-4 carbon atoms.Preferably, the N-substituted aziridine compound is produced at a high yield by subjecting an N-substituted alkanolamine to a gas-phase catalytic dehydration reaction in the presence of a silicon-containing or phosphorus-containing catalyst under the conditions of reaction pressure=5-250 mmHg, reaction temperature=300.degree.-450.degree. C. and space velocity=50-500 hr.sup.-1 (STP).

Abstract: A process for producing a cyclic amine represented by the general formula ##STR1## wherein each of R and R' is selected from hydrogen, a methyl group and an ethyl group, and n is an integer of 2 to 5, which comprises vapor-phase intramolecular dehydration reaction of an alkanolamine represented by the general formula ##STR2## wherein R, R' and n are as defined above, said reaction being carried out in the presence of, as a catalyst, an oxide composition represented by the following formulaX.sub.a P.sub.b Y.sub.c O.sub.dwherein X is at least one element selected from transition metal elements of Groups I through VIII, lanthanide elements, actinide elements and elements of Group IIIA in the periodic table, Si, Ge, Sn, Pb, Sb and Bi, P is phosphorus, Y is at least one element selected from alkali metal elements and alkaline earth metal elements, O is oxygen, the suffixes a, b, c and d are the atomic ratios of the elements X, P, Y and O respectively, and when a=1, b=0.01-6, preferably 0.

Abstract: A catalyst for the vapor phase intramolecular dehydration reaction of an alkanolamine represented by the general formula ##STR1## wherein each of R and R' is selected from hydrogen, a methyl group and an ethyl group, and n is an integer of 2 to 5,to convert it into a cyclic amine represented by the general formula ##STR2## wherein R, R' and n are as defined above. The catalyst is an oxide composition represented by the following formulaX.sub.a P.sub.b Y.sub.c O.sub.dwherein X is at least one element selected from alkali metals and alkaline earth metals, P is phosphorus, Y is at least one element selected from B, Al, Si, S, Sc, Ti, Cu, Y, Zr, Nb, Mo, Sn, Sb, La, Ce, Ta, W, Tl, Pb, Bi and Th, O is oxygen, the suffixes a, b, c and d represent the atomic ratios of the elements X, P, Y and O, and when a=1, b=0.01-3 and c=0-100, and d is a value determined by a, b and c and the state of bonding of the constituent elements.

Abstract: A catalyst for the vapor phase intramolecular dehydration reaction of an alkanolamine represented by the general formula ##STR1## wherein each of R and R' is selected from hydrogen, a methyl group and an ethyl group, and n is an integer of 2 to 5, to convert it into a cyclic amine represented by the general formula ##STR2## wherein R, R' and n are as defined above. The catalyst is an oxide composition represented by the following formulaX.sub.a P.sub.b Y.sub.c O.sub.dwherein X is at least one element selected from alkali metals and alkaline earth metals, P is phosphorus, Y is at least one element selected from B, Al, Si, S, Sc, Ti, Cu, Y, Zr, Nb, Mo, Sn, Sb, La, Ce, Ta, W, Tl, Pb, Bi and Th, O is oxygen, the suffixes a, b, c and d represent the atomic ratios of the elements X, P, Y and O, and when a=1, b=0.01-3 and c=0-100, and d is a value determined by a, b and c and the state of bonding of the constituent elements.