A C T I O N OF C A T I O N - E X C H A N G E RESIN K U - 2 ON PRIMARY

A L C O H O L S - O F NORMAL STRUCTURE

(UDC 542.951.4)

N. I. S h u i k i n , N. A. P o z d n y a k , . and T. P. D o b r y n i n a

N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences, USSR Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1705-1707, September, 1964 Original article submitted January 30, 1964

Cation-exchange resins catalyze various organic synthesis reactions [i]. Amyl alcohol is dehydated in the presence of the sulfonated copolymer of styrene and divinylbenzene to give a mixture of tertiary amylenes [2, 3]. The cation-exchange resin, obtained from the polymerization of sulfonated phenol with formaldehyde acts in the same way as a dehydrating catalyst [4]. When the reaction is run at 210 ~ and higher for 45 h the main product of the dehydration of primary aliphatic and aromatic alcohols are ethers, the yield of which reaches 80%.

In this paper we studied the action of the cationite KU-2 (sulfonated product of the copolymerization of styrene with divinylbenzene) on the primary aliphatic alcohols of composition C s and C6-Ci0. It was shown by us that in the presence of KU-2 the primary n-heptyl, n-nonyl and n-decyl alcohols undergo dehydration with the formation of ethers and alkenes, depending on the experimental conditions used. At 135 ~ for 5 h the dehydration goes with the formation of ethers, the yield of which ranges from 75 to 80% Increasing the temperature and the reaction times leads to the predominant formation of alkenes.

TABLE I.

Alcohol

n-Propyl n-Hexyl The same n-Heptyl The same n-Nonyl The same

N R

W

n-Decyl The same

u

Dedhyrating Action of KU-2 on Primary Alcohols of Normal Structure

Amount

"~1KU-2,

l0 10 I0 10 t0 i0 l0

15 15 15 10 10 10

Reaction time, h T e m p .

~

of eat kenes alcohol ether

5 5 5 5 5 5 5 5 2

10 5 5 5

43,0

1;?o 10,0 51,2 33.2 57;7 17,7 10,2

2?3

165 135 150 135 145 140 125 135 135 135 135 135 135 140 "I 5O

95,0

9?,o 41,0 19,0 7,5 6,5 5,3 4,0

29,2 22,3 25,0 23,2

67,0 72,8 5,0

80,8 7,0

59,0 66,0 82,5 42,3 61,5 38,3 53, I 67,5 75,0 74,5

Yield of ether, % of theory

66,2 64,5 5,3

79,0 6,8

62,0 63,8 79,5 44,5 73,0 34,1 71,5 67,5 65,6 68,0

E X P E R I M E N T A L

Commercial KU-2 cationite was ground in a mortar and converted to the hydrogen form by treatment with 20% sulfuric acid solution, after which it was washed with water until neutral and then dried in the air at 50 ~ The air- dried cationite contained approximately 45% moisture, and its static bulk capacity-SBC, determined by the method described by Ryabachikov [5], was equal to 5. The air-dried cationite was then dehydrated by heating with toluene until no more water was evolved. The toluene was decanted from the dehydrated cationite, and the latter was then transferred to the reaction flask. The dehydration of the C6-Cz0 alcohols was run at atmospheric pressure, using

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TABLE 2. Constants of Obtained Ethers

Name of ether

Di -n-propyl D i -n -hexy l Di -n -hep ty l Di -n-nonyl D i -n -decy l

B. p. , ~ (p,

mm of Hg)

r 89--90 (74,6) 91 (11) 117 (8) 1'67 (9) 184 (9)

1,3833 1,4215 1,4295 1,4380 1,4421

d 20

0,7623 0,7943 0,8008 0,8135 0,8158

found

31,3 59,4 68,9 87,15 96,7

MR

calc,

31,5 59,3 68,5 85,97 96,2

Composit ion of ca ta lyza te , %

4P

20

! J A

o 2

I I I I t I

2 4 5 Number of experiments

Fig. t . Composition of ca ta lyza te as a function of the number of exper i - ments run: 1) Amount of dinonylether ; 2) amount of nonenes; 3) amount of nonyl alcohol.

mechan ica l stirring. The amount of alcohol taken for each exper i - ment was 0.25 mole. Here the effect of the amount of taken ca ta - lyst, the contact t ime and the temperature on the course of the de- hydration react ion was determined. The exper imenta l results are given in Table 1.

From the data in Table 1 it can be seen that the pr imary C6-C10 alcohols of normal structure, at 135 ~ for 5 h, in the presence of 10 ml of cat ioni te per 0.5 mole of alcohol , undergo dehydration with the pre- dominant formation of ethers, the yield of which is 64.5-79.5% of theory. Raising the temperature and increasing the react ion t ime re- sults in more comple te dehydration of the alcohols and the ca ta lyza te contains a larger amount of aIkenes (see Table 1). In the experiments with nonyl alcohol at 125 ~ it was shown that it is possible to repeatedly r e -use theca t ion i t e fo r the dehydration of alcohols. Thus, the ca t a - lyza te from the 6th exper iment , run using the same ca t ioni te sample contained 40~ of dinonyl ether and 6% of nonenes (Fig. 1). The de- hydration of n-propyl alcohol was run in an autoclave, under the in- herent vapor pressure, at 1650 for 5 h. The yield of dipropyi ether was 66.2~ of theory. The constants of the obtained ethers are given in Table 2.

S U M M A R Y

1. Cat ioni te KU-2 is a good cata lys t for the dehydration of pr imary alcohols to yield the corresponding ethers.

2. A simple method was developed for obtaining ethers in 64.5-79.5~ of the theore t ica l yield.

L I T E R A T U R E C I T E D

lo

2. 3. 4. 5.

N. G. Polyanskii, Uspekhi Khimii , 31, 1046 (1962).

E. G. Rozantsev, M. Ya. Klimenko, and A. E. Myshkin, Khim. Prom., 1961, No. 3, 172. S. M. Markevich, N. G. Polyanskii, and N. L. Potudina, Nef tekhimiya, 1, 230 (1961). Edouard Swistak et Pierre Mastagli , Compt. rend., 239, 709 (1954). D. I. Ryabchikov and I. K. Tsitovich, Ion-Exchange Resins and Their Use [in Russian], Izd. AN SSSR (19620.

Al l a b b r e v i a t i o n s of p e r i o d i c a l s in the a b o v e b i b l i o g r a p h y are l e t t e r - b y - l e t t e r t r a n s l i t e r -

at.ions of the abbreviations as given in the original Russian journal. Some or all of this peri-

odical l i t e r a t u r e m a y w e l l b e a v a i l a b l e in E n g l i s h t r a n s l a t i o n . A c o m p l e t e l i s t o f the c o v e r - t o -

c o v e r E n g l i s h t r a n s l a t i o n s a p p e a r s at the b a c k o f th i s i s s u e .

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