Ph.D., Ziyadullaev O.E., lecturer Abdurakhmanovà S.S.

Tashkent Chemical Technological Institute, Uzbekistan

SYNTHESIS OF AROMATIC ACETYLENIC ALCOHOLS

AND THEIR VINYL ESTERS

 

Acetylene hydrocarbons and various derivatives thereof, due to their high reactivity and availability is widely used in organic synthesis.

Homogenous-catalytic vinylation reaction on the basis of aromatic acetylene alcohols (AAÀ) MeOH-DMSO (MeOH- LiOH, NaOH and KOH) has been carried out and it was exposed that vinyl ethers (VE) synthesized desirable in the interval of 40-60% [1, 2].

When industrial implementation of heterogeneous catalytic processes have to adjust the speed and direction of chemical reactions, the mechanism of which is known only in the most general terms, and the catalysts are complex solids, properties which are still not fully understood, and that may include almost all the elements of the periodic the periodic system [3, 4].

In this study of heterogeneous catalytic process to synthesize certain vinyl esters of aromatic acetylenic alcohols in relatively high yields in the presence of MOH (MOH- LiOH, NaOH and KOH) systems impregnated activated carbon. The active component of the catalyst used hydroxides of sodium and potassium. The process carried out at different temperatures and reaction time.

In reaction Grinyara- Iotsicha using croton aldehyde and ketones (acetone, methyl ethyl ketone, methyl isopropyl ketone, pinokaline and acetophenone) phenyiacetylene by their interaction with the organomagnesium compound synthesized in the following respective compounds AAA- 1-phenyl-3-methylbutyn-1-ol-3 (I) 1-phenyl-3-methylpentyn-1-ol-3 (II) 1-phenyl-3,4-dimethylpentyn-1-ol-3 (III), 1-phenyl-3,4,4-trimethylpentyn-1-ol-3 (IV) 1,3-diphenylbutyn-1-ol-3 (V) and 1-phenylgekcyn-4-in-1-ol-3(VI). The scheme of the reaction has been offered as following [5].

here: R= -CH3, R'= -CH3; R= -CH3, R'= -C2H5; R= -CH3, R'= izo -C3H7, R= -CH3, R'= -C(ÑH3)3; R= -CH3, R'= -Ñ6H3, R= -H, R'= -ÑH=CH-CH3.

Synthesis process AAA method Grinyara- Iotsicha conducted at a temperature range -5-10 °C in the presence of solvents DEE and THF. The starting materials were taken in equimolar amounts. The results are shown in the table 1.

Table1.

Influence of the nature and duration of the reaction solvents

on the yield of AAA (temperature0– 5 oC)

ÀÀA

Products,%

solventDEE

solventTHF

ÀÀA

intermediate connections

ÀÀA

intermediate connections

Duration of reaction, 2 hour

I

75,0

18,3

87,4

6,5

II

68,4

23,4

83,5

10,2

III

56,4

29,5

74,5

15,3

IV

53,0

34,7

69,3

18,4

V

50,0

39,6

66,0

21,0

VI

64,3

26,4

79,0

14,1

Duration of reaction, 4 hour

I

78,6

13,2

89,6

4,5

II

71,8

17,4

85,0

7,6

III

60,6

21,6

75,2

13,0

IV

55,9

25,0

71,0

15,5

V

54,7

28,0

68,7

18,2

VI

68,0

20,0

81,2

12,2

Duration of reaction, 6 hour

I

67,3

24,8

82,2

11,4

II

62,4

27,0

77,6

17,0

III

52,4

37,0

69,5

18,4

IV

45,2

41,6

63,2

21,0

V

42,7

44,0

57,3

23,7

VI

58,6

35,6

70,6

17,4

here: I- 1-phenyl-3-methylbutyn-1-ol-3; II- 1-phenyl-3-methylpentyn-1-ol-3; III- 1-phenyl-3,4-dimethylpentyn-1-ol-3; IV-1-phenyl-3,4,4-trimethylpentyn-1-ol-3; V- 1,3-di-phenylbutyn-1-ol-3; VI- 1-phenylgecyn-4-in-1-ol-3.

The table shows that when using THF as solvent, increasing the reaction time from 2 to 4 hours, an increase yield. However, with increasing duration of synthesis up to 6 hours, a sharp fall of efficiency AAA exit.

The table shows that when the reaction is carried out in solvents DEE and THF in AAA is formed with a high yield. For example, with a reaction time 4 hours temperature -5- 0 oC in a solvent DEE, yield AAA: I- 78,8; II- 71,8; III- 60,6; IV- 55,9; V- 54,7 and VI- 68,0%, and in case of replacement solvent THF respectively 89,6; 85,0; 75,2; 71,0; 68,7 and 82,2%. Comparing the reaction results in different solvents shows that the average selectivity output y THF solvent by 13,0% more than the DEE. This reaction is due to the greater polarity of THF molecule compared to DEE.

Hence, vinylation reaction on the basis of AAÀ acetylene with higher base-catalytic system, The scheme of the reaction has been offered as following:

here: R= -CH3, R'= -CH3; R= -CH3, R'= -C2H5; R= -CH3, R'= izo -C3H7, R= -CH3, R'= -C(ÑH3)3; R= -CH3, R'= -Ñ6H3, MOH= LiOH, NaOH, KOH.

 

It has been observed the relatively maximum yield synthesis of VE AAÀ in the presence of MeOH-CsF-DMSO with higher base-system on the experiment's results.

The gained results show that as LiOH, NaOH and KOH are used in the system of CsF-MOH-DMSO as MOH, in each particular state the yield of product goes through maximum while the temperature is rising. It has been determined the increase of AAÀ on the series LiOH·CsF<KOH·CsF<NaOH·CsF in the selected catalytic systems. As temperature rose from 80 to 120 oC, the yield raised appreciably.

The selectivity of temperature 100oC state has been meant as the highest system for the process.

It can be explained that catalytic activity of presented system with the formation of CsOH and NaF in the system and its less solubility with the higher base-property of CsOH. In LiOH and KOH systems, the solubility of the formed LiF and NaF is higher, and in the system they are existed in the state of ion in the system, the balance specifies. Hereon, CsOHcouldn't perform completely activity. Owing to this LiOH+CsOH+LiF+CsF system is in charge of catalyst.

Table 2.

The influence of nature and temperature of catalysts on the yield of VE AAÀ (duration of reaction is 6 hours, solvent DMSO)

Catalyst

Temperature,

oC

I

II

III

IV

LiOH·CsF

80

44,3

38,2

33,3

56,0

100

49,0

46,6

42,9

59,4

120

51,1

48,4

46,3

58,0

KOH·CsF

80

49,6

45,2

40,2

57,4

100

57,4

52,0

40,7

66,4

120

58,3

55,7

49,6

67,3

NaOH·CsF

80

74,2

73,2

67,3

79,6

100

84,8

77,1

72,3

88,0

120

86,0

79,7

75,0

89,5

here: I- VE 1-phenyl-3-methylpentyn-1-ol-3; II- VE 1-phenyl-3,4-dimethylpentyn-1-ol-3; III- VE 1-phenyl-3,4,4-trimethylpentyn-1-ol-3; IV- VE 1,3-diphenylbutyn-1-ol-3.

 

It has been observed, vynilation process on the AAÀ higher base-system, reaction undergoes under top level along with the formation of polycomponent mixtures on the some stages. Herein, moving hydrogen of acetylene goes on base of stereo-regioselectivity, also its exchanging process does easily. Although investigations on the vinylation process of organic compounds including members of various classes hydroxyl group containing in their molecules have been carried out for years, reaction mechanism hasn't enough researched scientifically yet. At present having formed catalytic active center, reactions being carried out in the system MeO-CsF-DMSO, formation of metal solvates and having become interval metal complex possessing active center, counterbalances the function of catalyst.

The optimal conditions for the synthesis of AAA: equimolar ratio of the starting materials; temperature -5- 0oC, the solvent THF, the reaction time of 4 hours. In this case it has been determined that very maximum yield of product is I synthesized AAA – I- 89,6; II- 85,0; III- 75,2; IV- 71,0; V- 68,7 and VI- 81,2%.

On the basis of experimental studies identified the following series of reactions reactivity of ketones Grinyara- Iotsicha acetophenone < pinokalin < methylisopropylketone < crotonaldehyde < methylethyl ketone <acetone.

Conclusion, in order to synthesize VE AAÀ with higher yield 6 hour's process at 100 oC temperature in the system of NaOH-CsF-DMSO has been chosen. In this case it has been determined that very maximum yield of product is I=84,8%; II=77,1%; III=72,3% and IV=88,0%.

Literature

1. WeilT.F., SchreinerP.R. Organo catalytic alkynylation of aldehydes and ketones under phase-transfer catalytic conditions // European Journalof Organic Chemistry,V.24(237). 2005 pp. 2213-2219.

2. Ziyadullaev O.E., Turabjanov S.M., Ikramov A., Mahatova G.B. Theoretical foundations reaction homogeneously catalytic vinylation of acetylene alcohols. ÕV International scientific conference «High-Tech in Chemical Engineering-2014» 2014, Moscow (Russia). pp. 124.

3. Schmidt E.Y., Trofimov B.A., Zorina N.V., Mikhaleva A.I., Ushakov I.A., Alexandrov G.G., DyachenkoO.A. Synthesis of functionalized 3,4-dihydropyrans via rearrangement of the products of a one-pot diastereoselective assembly of ketones and acetylene // European Journal of Organic Chemistry,V.35 (482). 2010. pp. 6727-6730.

4. Ziyadullaev O.E. Synthesis Reactions Vinyl Ethersof Aromatic Acetylene Alcohols In The Alkali Phase// International Journal Of Engineering Sciences & Research Technology, V.4.(5).Ìày, 2015, ðð. 633-637.

5. Ziyadullaev O.E., Turabdjanov S.M., Juraev R.S., Abdurakhmanovà S.S. Synthesis of aromatic acetylene alcohols of the methods Grinyara-Iotsicha ÕI Miedzynarodowej naukowi-praktycznej konferencji «Europejskanauka XXI Powieka» Przemysl, Poland. 2015. V.15, pp. 88-91.