Process for preparing amino alcohols

A process for preparing amino alcohols, which comprises reacting a polyhydric alcohol containing at least one primary alcoholic hydroxyl group and at least one secondary alcoholic hydroxyl group and expressed by the following general formula ##STR1## wherein R.sup.1 is an alkyl group, R.sup.2 and R.sup.3 are identical or different and represent a hydrogen atom or a lower alkyl group an n is an integer of 0 to 3, With ammonia in the presence of specified hydrogenation catalyst thereby to aminate the secondary alcoholic hydroxyl group of the polyhydric alcohol selectively.

This invention relates to a process for preparing amino alcohols. More 
specifically, the invention relates to a process for preparing amino 
alcohols, which comprises reacting an aliphatic polyhydric alcohol 
containing at least one primary hydroxyl group and at least one secondary 
hydroxyl group in the same molecule, with ammonia to convert the secondary 
hydroxyl group of the polyhydric alcohol selectively to an amino group. 
Various methods have previously been proposed for producing compounds 
having an alcoholic hydroxyl group and an amino group in the same 
molecule. With the prior art methods, however, it is relatively difficult 
to prepare amino alcohols containing a primary alcoholic hydroxyl group 
and an amino group bonded to the secondary carbon in the same molecule. 
For example, a reaction of an epoxide of a 1-olefin with ammonia easily 
affords an amino alcohol. But this reaction selectively yields an amino 
alcohol having an amino group bonded to the primary carbon, and an amino 
alcohol having a hydroxyl group bonded to the primary carbon, i.e. 
2-amino1-ol, scarcely occurs. Thus, according to the conventional methods 
using 1-olefins or epoxides thereof as a starting material, it is 
extremely difficult to prepare 2-amino-1-ol selectively. 
In order to obtain 2-amino-1-ol selectively on the basis of the 
conventional information, a complicated process is required which, for 
example, comprises adding formaldehyde to an aliphatic nitro compound 
having a nitro group at the terminal carbon to form a 2-nitro-1-ol, and 
then reducing it. Such a method is not commercially desirable. 
On the other hand, various methods have previously been proposed for 
preparing aliphatic amines which comprise reacting aliphatic alcohols with 
ammonia in the presence of hydrogenation catalysts, preferably together 
with hydrogen, thereby to reduce the hydroxyl group of the alcohols to an 
amino group. It is known that Raney nickel, Raney cobalt, and reduced 
cobalt are effective catalysts that can be used in these methods. It is 
also known that such a reaction can be applied not only to aliphatic 
primary alcohols and aliphatic secondary alcohols, but also to other 
polyhydric alcohols such as ethylene glycol. However, studies have little 
been made as to the reductive amination of polyhydric alcohols containing 
a primary alcoholic hydroxyl group and a secondary alcoholic hydroxyl 
group in the same molecule, and it has not yet been clearly known what 
difference there is between the reactivities of these hydroxyl groups. 
Accordingly, it is an object of this invention to provide a commercial 
process for preparing amino alcohols containing at least one hydroxyl 
group in the primary carbon and at least one amino group in the secondary 
carbon. 
Another object of this invention is to provide a new process for preparing 
amino alcohols which comprises reacting a polyhydric alcohol containing at 
least one primary alcoholic hydroxyl group and at least one secondary 
alcoholic hydroxyl group in the same molecule, to convert the secondary 
alcoholic hydroxyl group in the polyhydric alcohol to an amino group. 
The above objects can be achieved in accordance with this invention by a 
process for preparing amino alcohols which comprises reacting a polyhydric 
alcohol containing at least one primary alcoholic hydroxyl group and at 
least one secondary alcoholic hydroxyl group and expressed by the general 
formula 
##STR2## 
wherein R.sub.1 is an alkyl group, R.sup.2 and R.sup.3 are identical or 
different and represent a hydrogen atom or a lower alkyl group and n is an 
integer of 0 to 3, 
with ammonia in the presence of a hydrogenation catalyst selected from the 
group consisting of a catalyst composed of cobalt and an oxide of a metal 
selected from the group consisting of iron, manganese, zinc, thorium, 
zirconium, lanthanum and uranium, and a catalyst composed of nickel and an 
oxide of a metal selected from the group consisting of iron, thorium and 
lanthanum thereby to aminate the secondary alcoholic hydroxyl group of the 
polyhydric alcohol selectively. 
The aliphatic polyhydric alcohol used as a starting material in the process 
of the present invention contains at least one primary alcoholic hydroxyl 
group and at least one secondary alcoholic hydroxyl group in the same 
molecule. Specific examples of the polyhydric alcohols include aliphatic 
1,2-glycols such as 1,2-propylene glycol, 1,2-butanediol, 
3-methyl-1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-decanediol, 
and 1,2-octadecanediol; or other glycols such as 1,3-butanediol, 
2-metyl-1,3-butanediol, 2-methyl-1,3-pentanediol, 1,4-pentanediol, 
1,3-hexanediol, 1,4-hexanediol, 1,4-heptanediol, and 
2-isopropyl-1,3-butanediol; and trihydric alcohols such as glycerol, 
1,2,4-butanetriol, and 1,2,6-hexanetriol. These polyhydric alcohols may 
contain at least one other substituent which does not retard the reaction, 
such as an amino, nitrile, amide, alkoxy, carboxyl, carboxylate ester, or 
tertiary alcohol group. 
Polyhydric alcohols which give the best results in the process of this 
invention are those in which the primary alcoholic hydroxyl group and the 
secondary alcoholic hydroxyl group are attached to adjacent carbon atoms, 
such as 1,2-glycols. With these 1,2-glycols, the secondary alcoholic 
hydroxyl group can be converted to an amino group with very good 
selectivity. With other polyhydric alcohols, such as the 1,3-glycols or 
1,4-glycols, in which the two types of hydroxyl group are spaced from each 
other by at least three carbon atoms, the selectivity tends to become 
somewhat lower. 
It is interesting to note that when the process of this invention is 
applied to a primary aliphatic monoalcohol and a secondary aliphatic 
monoalcohol, there is no great difference in reactivity between them, and 
that when for example a mixture of these alcohols (e.g., a mixture of 
n-butanol and sec-butanol) is used in the reaction, there is hardly any 
different in reactivity between the primary monoalcohol and the secondary 
monoalcohol. 
Surprisingly, it has been found that when the polyhydric alcohol, above 
all, 1,2- or 1,3-glycol, is reacted with ammonia in the presence of a 
hydrogenation catalyst in accordance with the process of this invention, 
the secondary alcoholic hydroxyl group of the polyhydric alcohol is 
converted to an amino group with a good selectivity, and aliphatic amino 
alcohols can be obtained in good yields. 
Especially preferred polyhydric alcohols are those of the formula 
##STR3## 
wherein R.sup.1 is as defined above. 
A tertiary alcoholic hydroxyl group, even if contained in the starting 
polyhydric alcohol, is noted aminated under the reaction conditions of 
this invention. Accordingly, polyhydric alcohols containing primary, 
secondary and tertiary alcoholic hydroxyl groups at the same time can be 
converted to amino alcohols as a result of the amination of only the 
secondary alcoholic hydroxyl group with a high selectivity. 
The reaction in accordance with this invention is carried out in the 
presence of a hydrogenation catalyst. Any catalysts having activity in 
hydrogenation reactions can be used in the present invention. Preferred 
catalysts have the ability to induce hydrogenation and dehydrogenation. 
Examples of suitable catalysts are reducible metals such as nickel, cobalt 
or copper, and noble metals such as platinum, palladium, ruthenium, and 
rhenium. Of these, the nickel-type or cobalt-type hydrogenation catalysts 
are especially superior. Specific examples of the cobalt-type catalysts 
are Raney cobalt, reduced cobalt or Urushibara cobalt, and specific 
examples of the nickel-type catalysts are Raney nickel, reduced nickel and 
Urushibara nickel. Of these, the reduced cobalt catalyst and the reduced 
nickel catalyst are especially superior. 
We have found that by using a catalyst consisting of the above cobalt-type 
hydrogenation catalyst or the nickel-type hydrogenation catalyst and a 
small amount of another metal or metal oxide, amino alcohols can be 
obtained in high yields and selectivities at a temperature of not more 
than 200.degree. C. Examples of suitable metals or metal components are 
iron, manganese, magnesium, aluminum, zinc, barium, cesium, thorium, 
cerium, zirconium, lanthanum, and uranium. The use of the additive metal 
or metal oxide has an effect of markedly increasing the catalytic 
acitivity of the cobalt catalyst or nickel catalyst, and prolonging the 
active lifetime of the catalyst. 
A catalyst composed of cobalt and an oxide of a metal selected from the 
group consisting or iron, manganese, zinc, thorium, zirconium, lanthanum 
and urenium, or a catalyst composed of nickel and an oxide of a metal 
selected from the group consisting of iron, thorium and lanthanum is 
especially superior. 
The amount of the additive metal or metal oxide varies according to the 
type of the metal, the form of the catalyst, or the method of preparation 
of catalyst (for example, the temperature at which the catalyst is 
calcined), but in terms of an atomic ratio to cobalt or nickel, it is 
0.01-1, preferably 0.01-0.6 for iron, 0.001-0.3, preferably 0.005-0.2 for 
cesium, lanthanum and zirconium, 0.001-0.20, preferably 0.02-0.10 for 
uranium and thorium, and not more than 0.3, preferably not more than 0.2, 
for manganese, magnesium, zinc, aluminum, barium, cesium, thallium, and 
other metals. 
If the amount is less than this range, the effect is small, and if it 
exceeds the above range, side-reactions such as a decomposition reaction 
may take place vigorously. 
The reduced cobalt catalyst and reduced nickel catalyst containing the 
above additive can be prepared by various catalyst preparation methods of 
which a precipitating method and a calcining method are preferred. 
The precipitating method comprises neutralizing a mixed solution of a 
cobalt or nickel salt and a salt of the additive metal, with an aqueous 
solution of an alkali such as sodium hydroxide, sodium carbonate or 
ammonium carbonate to form a precipitate, washing the precipitate with 
water, drying or calcining it, and then reducing it in a stream of a 
hydrogen gas at a temperature of 250.degree. to 450.degree. C. 
On the other hand, the calcining method involves pyrolyzing the above salt 
mixture to an oxide, and reducing the oxide in a stream of hydrogen at 
250.degree. to 450.degree. C. 
The catalyst of this invention may be supported on a known carrier such as 
silica, alumina, diatomaceous earth, kaolin, carborundum, or silicon 
carbide. 
Since the activity of the catalyst of this invention can be maintained for 
a longer period of time in the presence of hydrogen, the reaction is 
performed preferably in the presence of hydrogen. Advantageously, the 
partial pressure of hydrogen is at least 1 atmosphere, preferably 10 to 30 
atmospheres. 
The reaction temperature is affected by various factors such as the type of 
the catalyst used, but is usually 100.degree. to 300.degree. C., 
preferably 120.degree. to 250.degree. C. The desired amino alcohol can be 
obtained more selectively when the reaction is carried out at a relatively 
low temperature within the above range using a catalyst having the highest 
possible activity. At relatively high temperatures, there is an increased 
formation of a by-product resulting from the amination of the primary 
alcoholic hydroxyl group of the starting material, and marked 
side-reactions tend to occur such as the conversion of the resulting 
amines to secondary amines or the hydrogenating decomposition of the 
resulting amines. From this standpoint, the most preferred temperature is 
120.degree. to 200.degree. C. 
Preferably, the amount of ammonia is stoichiometrically in excess of the 
polyhydric alcohol, because small amounts lead to the formation of larger 
amounts of by-products such as secondary or tertiary amines. For example, 
it is at least 3 moles, preferably at least 5 moles, per mole of the 
starting polyhydric alcohol. 
The reaction in accordance with this invention can be performed either in 
the vapor phase or in the liquid phase, but is preferably carried out in 
the liquid phase. 
The reaction can also be carried out in the presence of a solvent. Examples 
of the solvent are hydrocarbons such as n-hexane, cyclohexane, benzene, 
toluene or xylene, ethers such as diethyl ether, tetrahydrofuran or 
dioxane, esters such as ethyl acetate, amides such as dimethylformamide or 
dimethylacetamide, and nitriles such as acetonitrile, all of which are 
inert to the reaction. The amount of the solvent is not particularly 
restricted. 
When the reaction is carried out in the liquid phase, the process can be 
performed either continuously or batchwise using a pressure reactor. The 
reaction pressure in this case is desirably 100 to 600 atmospheres 
although varying according to the reaction temperature, the type and 
proportion of the starting substances, or the presence or absence of the 
solvent. The preferred partial pressure of hydrogen is 10 to 300 
atmospheres. 
On the other hand, when the reaction is carried out in the vapor phase, the 
pressure may be either reduced, atmospheric, or elevated. Generally, it is 
desirable to perform the reaction at atmospheric pressure or a pressure 
near it. The vapor-phase reaction can be performed by vaporizing the 
starting material, mixing it with ammonia gas, preferably further with 
hydrogen gas, and heating the resulting gaseous mixture to a temperature 
in the above range, followed by contacting it with the catalyst. 
The amino alcohols obtained by the present invention are useful as 
medicines and their intermediates.

The following Examples illustrate the process of this invention in greater 
detail without any intention of limiting the invention thereto. 
EXAMPLES 1 TO 4 
A 300 ml. vertically stirred autoclave was charged with 1.8 g (0.2 mole) of 
1,2-butanediol, 85 g (5 moles) of ammonia and each of the Raney catalysts 
shown in Table I, and hydrogen was introduced to a pressure of 30 
atmospheres at room temperature. 
The temperature was raised, and the reaction was carried out at a 
prescribed temperature for a prescribed period as indicated in Table I. 
After the reaction, ammonia was driven off, and the product was 
quantitatively analyzed by gas-chromatography. The results are shown in 
Table I. 
Table I 
______________________________________ 
Moie 
Con- Selecti- 
ratio of 
version 
vity of 
2-amino- 
Exa- Tempera- of 1,2- 
2-amino- 
butanol 
to 
mple ture Time butane- 
butanol 
1-amino- 
diol 
No. Catalyst (.degree. C.) 
(hr) (hrs) (%) butanol 
______________________________________ 
1 Raney Co. 
220 3 69 21 5.0 
2 Raney Ni 220 3 50 27 2.8 
(A) 
3 Raney Ni 220 3 75 19 1.1 
(B) 
4 Raney Cu 200 2 8 54 2.2 
______________________________________ 
The Raney nickel (A) was prepared by developing a powder of an alloy 
containing Ni and Al in a ratio of 30 to 70. The Raney nickel (B) was 
prepared by developing a powder of an alloy containing Ni and Al in a 
ratio of 50 to 50. 
In this and following Examples, the conversion of 1,2-butanediol and the 
selectivity of 2-aminobutanol were calculated in accordance with the 
following equations. 
##EQU1## 
EXAMPLES 5 TO 7 
A reduced cobalt catalyst was prepared as follows: 
106 g of sodium carbonate (Na.sub.2 CO.sub.3) was dissolved in 2 liters of 
water, and with stirring, a solution of 292 g of cobalt nitrate 
[Co(NO.sub.3).sub.2.6H.sub.2 O] in 2 liters of water was added dropwise to 
the resulting solution over the course of about 2 hours. After the 
addition, the mixture was allowed to stand overnight, washed several times 
by decantation, filtered, and then dried overnight at 110.degree. C. The 
dried powder was pyrolyzed at 300.degree. C., molded into tablets with a 
size of about 5 mm in diameter and about 2 mm in thickness, and then 
reduced in a stream of hydrogen kept at about 350.degree. C. 
Using 10 g of the resulting catalyst, each of the starting polyhydric 
alcohols shown in Table II was reductively aminated in the same autoclave 
as used in Example 1. The amount of the starting polyhydric alcohol was 
0.3 mole, and the amount of ammonia was 6.0 moles. The reaction was 
carried out at 180.degree. C. for 3 hours. The initial partial pressure of 
hydrogen at room temperature was 50 atmospheres. The results obtained are 
shown in Table II. 
Table II 
______________________________________ 
Conversion 
of the Hole ratio of 
Exa- starting Selectivity of 
2-amino-1-ol 
mple Starting material 2-amino-1-ol 
to 
No. alcohol (%) (%) 1-amino-2-ol 
______________________________________ 
5 1,2- 
propylene 34 57 11.3 
glycol 
6 1,2- 
butanediol 
51 55 5.4 
7 1,3- 
butanediol 
57 39.sup.*1) 
2.0.sup.*2) 
______________________________________ 
.sup.*1) Selectivity of 3-amino-1-ol 
.sup.*2) Mole ratio of 3-amino-1-ol to 1-amino-3-ol 
EXAMPLES 8 TO 10 
Commercially available cobalt oxide was molded into tablets each having a 
thickness of 2 mm and a diameter of 6 mm, calcined at 1350.degree. C. for 
1 hour, and reduced in a stream of hydrogen to 300.degree. to 350.degree. 
C. to prepare a calcined reduced cobalt. Using 10 g of this catalyst, 
propylene glycol or 1,2-butanediol was reacted in a 300 ml. autoclave. The 
amount of the starting alcohol was 0.3 mole, and the amount of ammonia was 
5.0 moles. The initial partial pressure of hydrogen was 50 atmospheres. 
The reaction was carried out for 3 hours at each of the temperatures 
indicated in Table III. The results are shown in Table III. 
Table III 
______________________________________ 
Conversion Mole 
Reaction of the Selectivity 
ratio of 
Exa- tempera- starting 
of 2-amino- 
2-amino- 
1-ol 
mple Starting ture material 
1-ol to 1-amino- 
No. alcohol (.degree. C.) 
(%) (%) 2-ol 
______________________________________ 
8 1,2- 
propane- 200 52 60 4.9 
diol 
9 1,2- 
butane- 180 21 71 5.3 
diol 
10 1,2- 
butane- 200 44 54 4.0 
diol 
______________________________________ 
EXAMPLES 11 TO 39 
With stirring, a solution of 109 g (1.03 moles) of sodium carbonate 
(Na.sub.2 CO.sub.3) in 2 liters of water was added dropwise to a solution 
of 277 g (0.95 mole) of cobalt nitrate [Co(NO.sub.3).sub.2.6H.sub.2 O] and 
20 g (0.05 mole) of ferric nitrate [Fe(NO.sub.3).sub.3.9H.sub.2 O] in 2 
liters of water. The resulting precipitate was treated in the same way as 
in the preparation of reduced cobalt in Examples 5 to 7 to form a 
Co--Fe.sub.2 O.sub.3 catalyst (Co/Fe atomic ratio 95/5). By the same 
precipitating method, catalysts containing various metal oxides were 
prepared. Using 10 g of each of the catalysts so prepared, 3.0 moles of 
1,2-butanediol was reacted with 6.0 moles of ammonia in a 300 ml. 
vertically stirred autoclave. The initial partial pressure of hydrogen was 
50 atmosphere. The results are shown in Table IV. 
Table IV 
______________________________________ 
Conver- Selecti- 
Mole ratio 
Reaction sion of vity of of 2-amino- 
Exa- Catalysts 
tempera- 1,2-butane- 
2-amino- 
butanol to 
mple (atomic ture diol butanol 1-amino- 
No. ratio) (.degree. C.) 
(%) (%) butanol 
______________________________________ 
11 Co-MgO 180 22 60 5.3 
(95-5) 
12 " 200 54 50 3.6 
13 Co-ZnO 160 9 43 15.3 
(90-10) 
14 " 180 58 43 7.2 
15 Co-MnO 180 18 77 11.0 
(95-5) 
16 " 200 51 37 4.8 
17 Co-ZrO.sub.2 
160 67 56 8.6 
(95-5) 
18 " 180 84 12 6.6 
19 Co- 140 34 78 25.6 
La.sub.2 O.sub.3 
(95-5) 
20 " 160 68 79 10.3 
______________________________________ 
21 Co- 180 33 65 3.8 
Fe.sub.2 O (99-1) 
22 " 200 72 33 3.7 
23 Co- 160 17 93 13.8 
Fe.sub.2 O.sub.3 
(95-5) 
24 " 180 55 81 9.6 
25 Co- 160 26 93 13.6 
Fe.sub.2l O.sub.3 
(90-10) 
26 " 180 61 85 9.9 
27 Co-FeO.sub.3 
200 18 32 7.7 
(50-50) 
28 " 220 40 50 4.0 
29 Co-Cs.sub.2 O 
180 21 73 4.6 
(95-5) 
30 Co-BaO 160 21 70 4.7 
(95-5) 
31 Co-UO.sub.2 
140 31 70 11.4 
(98.2) 
32 " 160 65 84 9.9 
33 Co-ThO.sub.2 
140 61 76 21.2 
(98-2) 
34 Co-ThO.sub.2 
160 65 92 20.0 
(99-1) 
35 Co-ThO 160 65 91 21.9 
(99.5-0.5) 
36 Co-T10 170 15 81 4.7 
(98-2) 
37 Co-ZnO 180 17 84 9.4 
(98-2) 
38 Co- 140 32 72 18.8 
ThO.sub.2 - 
Fe.sub.2 O.sub.3 
(97-1-2) 
39 " 160 64 86 14.5 
______________________________________ 
EXAMPLES 40 TO 45 
Using a catalyst consisting of cobalt prepared in the same way as in 
Examples 11 to 38 and a small amount of each of various metal oxide, 
1,2-propylene glycol was reductively aminated. The results are shown in 
Table V. 
Table V 
______________________________________ 
Conversion 
Selecti- 
Mole ratio 
Reaction of 1,2- vity of 
of 2-amino 
tempera- propylene 
2-amino 
propanol to 
Ex. ture glycol propanol 
1-amino 
No. Catalyst (.degree. C.) 
(%) (%) propanol 
______________________________________ 
40 Co-ZrO.sub.2 
180 63 51 4.6 
(99-1) 
41 Co-T10 180 39 54 6.4 
(98-2) 
42 Co-ZnO 180 33 48 15.9 
(98-2) 
43 Co-ThO.sub.2 
180 96 52 6.5 
(99-1) 
44 Co-La.sub. 2 O.sub.3 
160 62 76 13.2 
(95-5) 
45 Co-Fe.sub.2 O.sub.3 
170 62 50 18.5 
(95-5) 
______________________________________ 
REFERENTIAL EXAMPLE 1 
Using the same Co-La.sub.2 O.sub.3 (95-5) as used in Examples 19 and 44, a 
mixture of 0.2 mole of n-butanol (CH.sub.3 CH.sub.2 CH.sub.2 OH) and 0.2 
mole of sec-butanol [CH.sub.3 CH.sub.2 CH(OH)CH.sub.3 ] was reacted at 
140.degree. C. for 3 hours with 6.0 moles of ammonia in a 300 ml. 
vertically stirred autoclave using hydrogen at an initial pressure of 50 
atmosphere. 
After the reaction, the product was analyzed by gas-chromatography. It was 
found that the conversion of n-butanol was 32%, and the selectivity of n 
-butylamine was 84%, and that the conversion of sec.-butanol was 35%, and 
the selectivity of sec.-butylamine was 80%. Accordingly, the ratio of the 
conversion of sec.-butanol to that of n-butanol was about 1.1, and the 
ratio of the yield of sec.-butylamine to that of n-butylamine was 1.04. 
EXAMPLES 46 TO 55 
Catalysts were prepared by adding a small amount of each of the metal 
oxides shown in Table VI to nickel in the same way as in the preparation 
of cobalt metal oxide catalysts. Using each of the resulting catalysts, 
1,2-butanediol was reductively aminated. The results are shown in Table 
VI. 
Table VI 
______________________________________ 
Selecti- 
Mole ratio 
Reaction Conversion 
vity of 
of 2-amino- 
tempera- of 1,2- 2-amino- 
butanol to 
Ex. ture butanediol 
butanol 
1-amino- 
No. Catalyst (.degree. C.) 
(%) (%) butanol 
______________________________________ 
46 Ni-Fe.sub.2 O.sub.3 
180 17 43 4.9 
(90-10) 
47 " 200 37 46 3.2 
48 Ni-Fe.sub.2 O.sub.3 
160 20 43 14.4 
(80-20) 
49 " 180 40 71 9.7 
50 " 200 72 61 6.2 
51 Ni-ThO.sub.2 
160 19 53 24.3 
(99-1) 
52 " 180 36 62 15.1 
53 Ni-La.sub.2 O.sub.3 
140 18 47 36.9 
(95-5) 
54 " 160 41 91 18.5 
55 " 180 60 76 10.7 
______________________________________ 
EXAMPLES 56 TO 58 
Using 5 g of each of commercially available 5% Pt on carbon, 5% Pd on 
carbon, and 0.5% Ru on carbon, 0.25 mole of 1,2-butanediol was reacted 
with 5.0 moles of ammonia at 200.degree. C. for 3 hours using hydrogen at 
an initial pressure of 50 atmospheres in a 300 ml. autoclave. The results 
are shown in Table VII. In all cases, considerable amounts of secondary 
amines were formed as by-products. 
Table VII 
______________________________________ 
Conversion 
Selectivity 
Mole ratio of 
of 1,2- of 2-amino- 
2-aminobutanol 
Ex. butanediol 
butanol to 1-amino- 
No. Catalyst (%) (%) butanol 
______________________________________ 
56 5% Pt on C 48 7.7 2.1 
57 5% Pd on C 34 2.4 1.8 
58 0.5% Ru on C 
84 6.1 21.0 
______________________________________ 
EXAMPLE 59 
This Example illustrates the preparation of 2-amino-1-butanol from 
1,2-butanediol by the vapor-phase process. 
(a) Preparation of Catalyst 
A solution of 263 g (0.9 mole) of cobalt nitrate 
[Co(NO.sub.3).sub.2.6H.sub.2 O] and 24 g (0.1 mole) of copper nitrate 
[Cu(NO.sub.3).sub.2.3H.sub.2 O] in 2 liters of water was added dropwise 
with stirring to a solution of 106 g (1.0 mole) of sodium carbonate 
(Na.sub.2 CO.sub.3) in 2 liters of water. The resulting precipitate was 
allowed to stand overnight, washed with water, dried, calcined, and molded 
into tablets. The tablets were reduced in a steam of hydrogen at 
200.degree. to 250.degree. C. to prepare a catalyst with a composition 
Co-Cu (90-10). 
(b) Procedure of Reaction 
40 g of the above catalyst was filled in the central portion of a reaction 
tube with a diameter of 20 mm and a length of 1 m, and the temperature of 
the catalyst layer was maintained at 180.degree. C. 
1,2-Butanediol was vaporized at a rate of 5 g/hour, and mixed with 0.10 
liter/min. of ammonia gas and 0.25 liter/min. of hydrogen gas. The gaseous 
mixture was pre-heated to 180.degree. C., and passed into the catalyst 
layer. The reacted gas which passed through the catalyst layer was 
collected on a dry ice-methanol cooling medium, and quantitatively 
analyzed by gas-chromatography. 
It was found that the conversion of 1,2-butanediol was 50%, and the 
selectivity of 2-amino-1-butanol was 8%. 1-Amino-2-butanol was scarcely 
detected, but considerable amounts of by-product secondary amines were 
formed.