DE2550902A1 - PROCESS FOR THE PREPARATION OF 3-ALCOXIBUTEN-1 AND ALKYL-TRANS-BUTYL ETHER - Google Patents

Description

Hamburg, 10.11.1975 547 / ik

D 75O13D

DEUTSCHE TEXACO AKTIENGESELLSCHAFT

2000 Hamburg 13 Mittelweg 180

Process for the preparation of 3 - A-lkoxibutene-1 and Alkyl-trans-butenyl ether

The invention relates to a process for the preparation of 3-alkoxibutene-1 and alkyl-trans-butenyl ethers. These connections are valuable starting materials for a number of syntheses. Production is an example of this of saturated ethers by hydrogenation of the double bond; of vinyl-alkyl-ketones by selective oxidation the 3-alkoxibutenes; of vinyl methyl ketone by selective Oxidation of 3-methoxibutene-1.

3-Methoxi-buten-1 is so far for example by catalytic Addition of methanol to 1,3-butadiene with Ehodiumchlorid as Catalyst made. Pur the synthesis of methyl transbutenyl ether several suggestions have been made. According to IJS-PS 3,577,466, 2-buten-i-yl alcohol is mixed with methanol in the presence of calcium chloride as a catalyst and acid as a promoter under pressure at elevated temperature in the Ether transferred. The 2-buten-1-yl alcohol has also been converted into butenyl chloride and this with methanol converted to the desired ether in the presence of sodium.

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A mixture of 95% trans, 4.5% cis ether and 0.52 other substances obtained. In the case of the Journ. Org. Chem. Vol. 32C5) 1967, pp. 1307-1311 described synthesis of Methyl trans-butenyl ethers are derived from trans-1-methoxy-1,3-butadiene and stores hydrogen in the presence of a catalyst in the 1,4-position. These known methods So all of them start from raw materials that are not freely available. By none of these procedures both ethers can be preserved at the same time.

The invention is based on the "object of creating a process by which 3-alkoxibutene-1 and alkyltrans-butenyl ethers can be produced side by side. It should be assumed that a material is sufficient Amount is available. Finally, the process should be suitable for working on an industrial scale be.

The problem is solved by a method of production of 3 - A-lkoxibutene-1 and alkyl-trans-butenyl ether Reaction of olefinic material with an alkanol in the presence of ion exchangers containing sulfonic acid groups, which is characterized in that as olefinisch.es Material butadiene or a butadiene-containing C. stream used and the reaction at temperatures in the range of 90-14-O ° C and below at least one for liquefaction. sufficient pressure is applied to the olefinic material.

The production of ethers by reacting olefins with alcohols on acidic cation exchangers is known. In particular, this process is used to produce tertiary butyl alcohol from isobutene or Ιε) butene-containing CL cuts. For example, OS-PS k 24-6 OO3 recommends dehydrogenating isobutane in CL cuts to isobutene in a dehydration zone and then converting it to tertiary butyl ether in an etherification zone.

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As a starting material for the reaction of olefins with alcohols on acidic ion exchangers, one has so far only Olefins or hydrocarbon mixtures with olefins with double-bonded tertiary carbon atoms used, mainly isobutene, but also 2,5 ~ dimethylhexadiene. An explanation for this can be found in DT-PS 1 224-294-. The publication shows that the reaction rate of isobutene is many times greater is than that of olefins which do not have a double bonded tertiary carbon atom, such as propylene, n-butene-1 or butene-2. According to column 3, lines 18-22 of this patent specification, before the etherification of the in CL cuts Isobutene contained the butadiene separated.

It has now surprisingly been found that the known Etherification can also be carried out with butadiene as the starting olefin, and the two desired ethers, the 3-alkoxy-buten-1 and the alkyl-trans-butenylether occur side by side. It was not to be expected that under the same conditions as those (e.g. from the DT-PS 868 14-7) known process for the etherification of 'isobutene be applied, the etherification of butadiene can also be made, although its doubly bonded C atoms are not tertiary C atoms.

It is particularly surprising that, during the etherification, both desired ethers are next to each other in almost equal amounts can be obtained. Rather, it was to be expected that, if the reaction were to take place at all to any significant extent would, primarily one of the two possible ethers would be formed.

In the practical implementation of the process according to the invention, butadiene or a butadiene-containing C ^ stream is used as oleic starting material and a saturated aliphatic table straight or branched alcohol with

1-6 carbon atoms, such as methanol, ethanol, propanol, tertiary lower
Butanol, as alkanol. ;

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The olefinic material we :! ^{heated to a temperature of about 100-13O 0} G with at least an amount equal to the molar amount of butadiene A.Lkanol in the presence of an acidic cation exchanger, and a pressure generated which is at least high enough that the butadiene or the C ^ -cut is liquefied, so that a single phase reaction takes place. In general, a pressure of 45-55 bar is sufficient. Higher pressures can be used, but do not bring any advantage. The required reaction time depends primarily on the olefinic starting material, ie on the concentration of the butadiene in the starting material. An excess of alkanol also has a favorable effect on the yield have been found when the molar ratio of butadiene to alkanol is in the range of 1: 1-1: 5, with a ratio of 1: 2. The longer the reaction time, the greater the yields will of course be obtained, but the time and yield should be be in a reasonable relationship. '

Cool off! as ^ on and unwind separates .sich the reaction mixture in two Phasen.Die lower phase predominantly consists of alkanol, containing din upper, frewünsohten ether addition vinylcyclohexane and small amounts of unreacted starting material, and if ^ ron assumed a C ^ stream λ ' / orrien is also the ethers of the other olefins which were contained in the stream. The desired ethers can easily be separated off, for example by fractional distillation or in a preparative gas chromatograph.

The process can be either discontinuous or continuous be performed. If you work discontinuously, the »pressure im Autoclaves generated by means of an inert gas, preferably nitrogen. The reaction times are 5-30 hours, preferably 10 h. When working continuously, the Space flow velocities and the contact time of the Concentration of butadiene in the olefinic starting material

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25503

(t

depends on the catalyst used, in particular its particle size, as well as the length and diameter of the catalyst bed. Those ieweils best Raumströmungsgesclx ^<r indigkeltnn can be determined by a person skilled in known Weire.

As an ion exchanger, all can be used for the etherification of Isobutene known to be suitable can be used. These are all cation exchangers containing sulfonic acid groups, e.g. sulfonated phonol-formaldehyde resins (Amberlite IR-1, IR 100, itfalcite MX), sulfonated polymers of coumarone-indene-cyclopentadiene and / or -Furfural. Sulfonated polystyrene crosslinked with divinylbenzene (Dowex 50, NaIcj te HCR and Amborlyst 15). ·

The invention is illustrated by the examples below explained.

example 1

About 10 g of a cation exchange resin, a polystyrene containing sulfonic acid groups, crosslinked with divinylbenzene and having an average toilet diameter of 0.1-0.8 mm micron, were placed in a 2 liter autoclave equipped with a stirrer. Thu vmrden 160 g (about - 5 Hol) methanol and 530 g of C / -Kohlenwesserstoff-Goses de "in Table I below ango ^ surrounded Zusamnensotznng initiated closed dor autoclave and heated to 130 ⁰ C After reaching this?.. TemperatiJ.r Var the pressure on the autoclave? 3 risen bar. Then the pressure wnirde d \ jrch introducing brought to 50 bar and maintained. the heating to 130 ° at 50 bar nitrogen vmrde? continued Λ hours. allowed to cool, and weighting Relaxation vurclon? 95 g of a liquid was obtained, which separated into 2 phases. The lower phase of approx. 30 g consisted predominantly = ms methanol, the upper phase of approx. 390 g was analyzed by gas chromatography

709821/1021

can be found in Tabel7.e I. The methyl trann-butenyl ether and 3-methoxybutene-1 were separated off in a prnnutrient gas chroma to graxjhen. The IR as well as IMR connections confirmed that it was about these two ethers acted.

Table I.
Get together. ·? of use s

i-butane 1.1 wt ^ ¹

n-butane 6.3 wt

Butene- C1) 21, 4 Gevf. -%

iso-ßuten 0.8 wt -.%

trens-Jduten- (?) 9.8 wt. 96

ci.?- Butene-C ⁹ ) 6.7 Gow .- ^

Butndione- (1. ^) 5?,? W / w%

tert. Butylmetbyl ^ thor 1.7 wt. 90

100.0 wt. -96

Composition de. ¹ =: Renaction product

130 ⁰ C, 7 ^ bar. 4. ^ h Upper phase Lower phase

C _{/ +} gas 0.3 Gev /.-# 0.2 wt .-? O

tert-butyl methyl ether 3.4 wt. 96 3.6 wt. 96

sec. Butyl methyl ether 11.1 wt. 96 7.6 wt. 96

3-Methoxibuten-1 15.8 wt -.% 11.2 wt -.%

Methyl-tranh butenv-i / ither 24.6 wt.% ~ 17.3 parts by weight-96

tert. Butanol 3.1% by weight 2.9% by weight 6

Methanol 5.2 wt .-% ^ 29.1 wt .-%

sec. Bi.itnnol 4.0 r> \ '.-% 7.5% by weight

4-Vinyloyclohexan ^ d, 8 wt .-? 6. 9.0 wt% "

-Unknown 3.3 wt. -96. 11.6 wt. 96

100.0 wt. 96 100.0 wt. 96

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Example ?

The procedure was as described in Example 1, but instead of the C 1 -C hydrocarbon gas, pure butadiene, 54 g (1 mol), approximately a 3-fold excess of methanol, 96 g (3 mol) was used. The reaction mixture was ^{fetched for 15 hours at 120 °} C. and 30 bar. After cooling down, letting down the pressure and phase separation, 110 g of the upper phase were obtained, the composition of which was determined by gas chromatography. The results of the analysis are shown in Table II under column A.

Tnbelle Il

But η dien weight ^and / or 0 ,? 13.8 14.1

3-methoxibutene-1 wt% 17.7 1.7 6.4

Methyl trans-butenyl ether wt % 19.4 1.4 7.0

tert-butanol wt .-% 2.1 -

Methanol wt .-? 6 34.8 -79.7 60.1

4-vinylcyclohexene wt% 25.4 3.4 12.4

Other 0 »3 ^ -

Wt. ~% 99.9 100.0 100.0

Example 3

Example 2 was repeated, but the reaction conditions were changed. Dns reaction mixture was held for 4 hours at 100 ⁰ C and 30 bar. After allowing to cool, let down and phase separation, 65 g of upper phase were obtained. The result of the gas chromatographic analysis of this phase is shown in Table II, column B.

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Example 4

Example 2 was repeated, but the working conditions were changed. The reaction mixture was "4 hours at 120 ⁰ C and 0 b ^ r -. Ehalten RJ> oh cool,, relax and phase separation were obtained 85g upper phase and the result of gapohromatographlGchen \ nalyr.e is shown in Table II, Column C?.. reproduced.

Example 5

It was like in example ? worked, but used n-butanol instead of methanol. En wairden 54 g (1 mol) of butadiene with 7O ^ rr (5 mol) of n-but-.nol reacted. Mn.oh Abkiihleni.o.jspn "and relax

420g mixture obtained. The result of the gasohronatogi "aphlschen Table III is attached to this mixture remove.

Tabel Butadiene III -% 7.1 3> 7-Butoxibiitcn ~ 1 Weight c /. 6.4 Di-n-buty.lether Weight -% 18 ,? sec-butanol Weight -% 1.6 4-vinylcyclohexene Gw. -% ^, 1 n-buty 1 -1 ra η π - but. eny 1 a the r Weight, 0 /.
/ '' '», 7 n-butanol Weight α / 54.4 miscellaneous Weight 2.5 Weight

Wt-55 100.0

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Claims (1)

D 75 015 P a t, ο η t a η s ρ r U c Vi e 1) Process for the preparation of 3-Alkoxl-buten-1 and Al kyl-trans-Buton ^ lnther by conversion of olefinic lower Material with a no-ra ^ alkenol in the presence of sulfonic acid group-containing cation exchangers, thus 5 e ke η η ζ e 1 ch η «t ·, that al8 ole-fi.ninches materia. 1 butadiene or a Butadienhaltigcr C.-Stream used and the reaction at an atur in the range of 90-140 ⁰ C and below a at least to liquefy the oleophilic material required pressure is made. ?.) Method according to claim 1, characterized by f?; e indicates that the alkanol is an aliphatic alcohol with 1-4 C atoms is used. 1/10 2 1 ORIGINAL