DE1212070B - Process for the preparation of secondary alkynols - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY GERMAN wl ^ PATENT OFFICE

EDITORIAL

Int. α .:

C07c

C07d
German: 12 ο -19/03

Number: 1212070

File number: L 34445IV b / 12 ο

Filing date: October 8, 1959

Opening day: March 10, 1966

In the German Auslegeschrift 1 125 909 a process for the production of tertiary alcohols was described the acetylene series (alkynols) by condensation of ketone compounds with acetylene or monosubstituted Proposed acetylene compounds.

The previously known reaction is the reaction between an aldehyde and a Metal derivative of an acetylene compound, possibly in the presence of an excess of the acetylene compound itself that leads to the formation of a metal alkynolate which then has to be hydrolyzed to produce the free Obtaining Alkynol leads.

U.S. Patents 2,106,181 and 2,125,384 describe a process in which an alkali metal acetylide with an aldehyde or a ketone «5 at very low temperatures not exceeding -33 ° C Temperatures is implemented. In patent 2125,384 it is stated that it is also possible to use the reaction to be carried out in a "semi-catalytic manner", d. That is, one works with an excess of acetylene and Acetone to obtain yields in excess of stoichiometric with respect to the alkali metal used Yield and a maximum value of 175%> that of a conversion of 1.75 moles of acetone per mole Alkali acetylide corresponds, can achieve. For this purpose, the reaction time is increased, the Reaction temperatures remain unchanged. It is further claimed that the reaction also occurs when increased pressure can be carried out, which, however, is disadvantageous (see US Pat. No. 2,106,181 and 2 125 384).

The alkynol is not the only reaction product, as diols are always formed according to the following scheme:

2 RCHO + C ₂ H ₂

RCH (OH) C ξ C · CH (OH) R

This process is beneficial in that only small amounts of catalyst are used, however Working with acetylene at high temperatures and pressures requires special process engineering (cf. Copenhaver and B i g e 1 ο w "Acetylene and Carbon Monoxide Chemistry", N.V., 1949).

The process according to the invention for the preparation of secondary alkynols of the general formula

RCH (OH) C = CR '

where R is an alkyl, or aryl, an alicyclic or heterocyclic radical which does not contain any groups capable of reacting with the catalyst, and R 'denotes hydrogen, an alkyl or aryl group, processes for the preparation of secondary
Alkynols

Applicant:

SNAM S. p. A., Milan (Italy)

Representative:

Dr. F. Zumstein,

Dipl.-Chem. Dr. rer. nat. E. Assmann

and Dipl.-Chem. Dr. R. Koenigsberger,

Patent Attorneys, Munich 2, Bräuhausstr. 4th

Named as inventor:

Leonard Turner,

Martino Dolci,

Marcello de Malde ', San Donato Milanese

(Italy)

Claimed priority:

Italy of September 22, 1959 (21 599)

by reacting an aldehyde of the general formula RCHO with an acetylene derivative of the general formula formula

R'C ξ CH

is characterized in that the reaction is carried out in liquid, anhydrous ammonia in the presence of an alkali metal or its acetylide at -40 to +40 ⁰ C and a pressure between 1.2 and 21 atmospheres. It is also possible to work at temperatures between and 25 ° C. The alkali acetylide can also be prepared in situ.

Under otherwise identical reaction conditions, the yields increase with increasing acetylene or acetylene compound partial pressure.

The reaction temperature is important because on the one hand it determines the extent of the side reactions, such as the Autocondensation of the aldehyde itself and, on the other hand, determines the reaction rate.

The amount of solvent is between at least twice the volume of that used Carbonyl compound and an upper limit determined by economic considerations is conditional.

In practice it has proven to be useful to add 1 mol of catalyst to 5 to 100 mol of carbonyl

609 537/428

3 4

connection to be used, although also lower than 20 ° C and at a total pressure of 16 atü

Amounts of catalyst lead to favorable results, if used, 0.040 mol of 2-methylpentine-

however, this requires long response times. 4-ol- (3) with a yield of 2.22 mol of reaction

The process can also be carried out continuously per mole of catalyst, which is one on the

be performed if you from the reaction vessel 5 applied aldehyde based yield of

the solution is continuously removed and the reagent corresponds to 8.1%.

Adds catalyst and solvent. _. . ₁ "

. _ "Example 6

Example 1 * ⁿ an autoclave with a capacity of about 500 ecm

ίο 0.0509 moles of potassium metal in 250 ecm dry

In an autoclave with a capacity of about 500 ecm, liquid ammonia is dissolved and, with the addition of a 0.0144 moles of potassium metal in 300 ecm dry trace amount of ferric nitrate nonahydrate in potassium ammonia converted to amide at a temperature of -40 ° C.

solved. With shaking, dry acetylene is now added. After half an hour, 0.5 mol of phenyl

pumped in, the temperature being added up to 1O ⁰ C 15 acetylene, the temperature increasing to 20 ⁰ C and and the total pressure up to 11.5 atmospheres. The total pressure can be kept at 6.4 atmospheres; Now add in small amounts, at a rate thereupon 0.5 mol of 0.15 to 0.5 mol per hour, 0.7 mol of dry isobutyric aldehyde are introduced over the course of 3 hours. A further acetaldehyde is added and allowed to react for one hour with shaking, and the reaction temperature of 10 ° C. is then isolated for a further 4 hours in the manner described in Example 1. 0.305 mol of 4-methyl-1-phenyl-4-hydroxy-

20 cc of water are added, which becomes ammonia pentine- (l) with a yield of 6 moles of reaction removed and the reaction product with one product per mole of potassium amide, which is one on the Solvent extracted and fractionated by phenylacetylene and applied to the aldehyde Distillation isolated. 35 related yield of 60% corresponds.

0.336 mol of butyn-1-ol- (3) is obtained with a. . ,

Yield of 23.3 moles of reaction product per mole of example /

Catalyst, which is one applied to the acetone If one proceeds in the manner described in Example 1

Aldehyde-related yield of 48% corresponds. goes ahead, but 0.0142 moles of potassium metal and 0.49 moles

30 benzaldehyde at a temperature of 20 ° C and at

Example 2 applies a total pressure of 16atü, so obtained

0.224Mol of 1-phenyl-1-hydroxypropyne- (2) with

If one proceeds in the manner described in Example 1, a yield of 15.8 mol of reaction product per, but 0.0136 mol of potassium metal and 0.49 mol of mol of catalyst, which is a result of the acetaldehyde used at a temperature of 0 ^° C. and at 35 speaks benzaldehyde related yield of 45.7 applying ° / ₀ enteinem total pressure of 6 atm so obtained.

0.272 moles of butynol with a yield of 20 moles of Example 8

Reaction product per mole of catalyst, what one

based on the applied acetaldehyde If you add 0.5 mol of isobutyric aldehyde with

prey of 55.5 ° / ₀ corresponds. 40 1.5 moles of hexyne- (l) in a solution of 0.0564 mol

Potassium metal in 250 ecm liquid and dry

Example 3 Ammonia at a temperature of 15 ° C and at

a total pressure of 6 atü can react, so

If one proceeds in the manner described in Example 1, a yield of 2.5 moles of 2-methylnonine is obtained, but 0.0138 moles of potassium metal and 0.49 moles of 45 4-ol- (3) per mole of catalyst.
Acetaldehyde at a temperature of 23 ⁰ C and at ...

applies a total pressure of 14atü, Example 9 is given

to be 0.357 mol of butynol with a yield of In a 600 ecm autoclave

25.6 moles of reaction product per mole of catalyst, which is 0.0144MoI potassium acetylide in 250 ecm dry a slurried based on the acetaldehyde used 50 dimethylformamide. At a tempe yield of 72%. ■ At 0 ° C, dry nitrogen is first turned on

pumped until the total pressure has risen to 7.5 atm

Example 4 is- The temperature is kept constant ^{at O 0 C,}

and without stopping the stirring, be using

If one proceeds in the manner described in Example 1 55 of an injection pump in the course of 1.5 hours, but introduced 0.0133 mol of potassium metal and 0.49 mol of 0.5 mol of isobutyric aldehyde. After loading isobutyric aldehyde at a temperature of 20 ⁰ C of the Isobuttersäurealdehydzusatzes termination is allowed to and applies atm with a total pressure of 16, continue to react for a further 2 hours, then the so obtained 0.453 mol of 2-Methylpentin-4-ol (3) broken with reaction by adding 20 ecm of water with a yield of 34Mol of reaction product per 60. ^:

Mole of catalyst, which is one applied to the one obtained 0.058 mole of 2-methyl-3-hydroxypentyne- (4)

Aldehyde-related yield of 92% corresponds. with a yield of 4 moles of reaction product per

Mol of catalyst, which corresponds to a yield of 12% based on the applied example 5 aldehyde.

If, in the manner described in Example 1, Example 10

proceeds, but as a catalyst 0.018 moles of barium metal If one in the manner described in Example 1

and 0.49 moles of butyric aldehyde takes place at one temperature, but instead of sodium metal as a catalyst

Applying potassium metal, 0.200 moles of butm-l-ol- (3) are obtained with a yield of 13.9 moles Reaction product per mole of catalyst, which is a yield based on the aldehyde used of 29%.

Example 11

If one proceeds in the manner described in Example 3, but instead of sodium acetylide as a catalyst Applying potassium metal, 0.211 moles of butyn-1-ol- (3) are obtained with a yield of 15.3 moles Reaction product per mole of catalyst, which corresponds to a yield based on the aldehyde used of 43% corresponds.

Example 12

If one proceeds in the manner described in Example 4, but instead of potassium amide as a catalyst Uses potassium metal, the yields are somewhat lower, namely 0.413 mol of 2-methylpentin-4-ol- (3) with a yield of 31 moles of reaction product per mole of catalyst, which is one on the applied aldehyde-related yield of 84% corresponds.

Example 13

If one proceeds in the manner described in Example 5, but instead of barium amide as a catalyst Using barium metal, 0.038 mol of 2-methylpentin-4-ol- (3) is obtained with a yield of 2.11 moles of reaction product per mole of catalyst, which is one based on the aldehyde used Yield of 7.7%.

Claims (4)

Patent claims: 1. Process for the preparation of secondary alkynols of the general formula RCH (OH) C = CR ' where R is an alkyl, or aryl, an alicyclic one or heterocyclic radical which does not contain any groups which are reactive with the catalyst contains, and R 'is hydrogen, an alkyl or aryl group, by reacting one Aldehydes of the general formula RCHO with an acetylene derivative of the general formula R'C = CH characterized in that the reaction is carried out in liquid anhydrous ammonia in the presence of an alkali metal or its acetylide at -40 to + 4O ⁰ C and a pressure from 1.2 to 21 atm. 2. The method according to claim 1, characterized in that the reaction is carried out ^{at 0 to 28 0C.} 3. The method according to claim 1 and 2, characterized in that the reaction is carried out in Carries out the presence of an in situ prepared alkali acetylide. 4. The method according to claim 1 to 3, characterized in that the catalyst in one Amount below 0.2 moles per mole of aldehyde applies. Considered publications:
German Patent Nos. 725 326, 740 988, 596, 816 097, 848 361;
U.S. Patent No. 2,712,560.