Method of producing phenylethynyl derivatives of aromatic compounds

FIELD: chemistry.

SUBSTANCE: method includes heating a mixture of components - 0.01 mol phenylacetylene, 0.01 mol iodobenzene (aryl iodide), 0.0006 g copper nanopowder and 0.002 g CuI at temperature of 110-120°C for 3 hours; after cooling, the reaction mass is poured into 100 ml cold water while stirring, followed by extraction with ethyl acetate, purification on a column with silica gel, elution with a solvent mixture with ratio of ethyl acetate to hexane of 1:6 and then distilling off the solvent to obtain pure products.

EFFECT: use of the present method enables to obtain end products with high output with considerable simplification of the process.

1 tbl

 

The invention relates to methods of organic synthesis, in particular to a method of synthesis phenylethynyl derivatives of aromatic compounds with the substitution of the iodine molecules in phenylacetylene, which are widely used in various fields, including in the manufacture of luminescent materials, and are used in chemistry, biology, and medicine.

Known methods of synthesis phenylethynyl derivatives of aromatic compounds with the substitution of the iodine molecules in phenylacetylene - this reaction with imprisonme occurs in the presence of base and palladium catalyst (Sonogashira) ().

Some patents have been used reaction type Sonogashira (benzodiazepine Derivative and drug containing, No. 2259360 EN, publ. 27.08.05; indole Derivatives containing an acetylene group, as PPAR activators, No. 2387639 EN, publ. 27.04.10; the Method of obtaining inhibitors of poly(ADP-ribose)polymerases, No. 2344138 EN, publ. 20.01.09; Triazolinone aminobenzophenone connection, No. 2394818 EN, publ. 20.07.2010). These reactions combination method Sonogashira preferably carried out using known catalytic mixtures of Pd(PPh3)4/CuI. B these systems were used amines as solvents, such as diethylamine, triethylamine, pyridine, etc. which, when evaporation is vzryvoopasnym and toxic.

A known method for the synthesis of phenylethynyl derivatives of aromatic compounds with the substitution of the iodine molecules in phenylacetylene (Catalytic Activity of Pd(II) Complexes with Triphenyl phosphito Ligands in the Sonogashira Reactionin Ionic Liquid Media, I.Błaszczyk A.M. Trzeciak J.J. Zio'łkowski, Catal. Lett. 2009, 133:262-266). When performing synthesis is necessary not only palladium, triethylamine, and the ionic liquid, and an inert atmosphere. To obtain a product in this way requires a complex installation, which is a disadvantage of the method.

A known method for the synthesis of phenylethynyl derivatives of aromatic compounds with the substitution of the iodine molecules in phenylacetylene (Tandem Sonogashira Coupling: An Efficient Tool for the Synthesis of Diarylalkynes. Zolta'n Nova'k, PE ter Nemes, and Andra's Kotschy. Organic Letters, 2004 Vol.6, No. 26, 4917-4920). But the synthesis should be carried out in two stages, first in the process is formed intermediate product between odensala and 2-methyl-3-butyn-2-I. Also the yields of target products is low and variable from 17 to 84%.

A known method for the synthesis of phenylethynyl derivatives of aromatic compounds with the substitution of the iodine molecules in phenylacetylene using CuI (Copper(I) Iodide Polyphosphine Adducts at Low Loading for Sonogashira Alkynylation of Demanding Halide Substrates: Ligand Exchange Study between Copper and Palladium, Matthieu Beaupérin, Andre Job, Hélène Cattey, Sylviane Royer, Philippe Meunierand Jean-Cyrille Hierso; Organometallics, 2010, 29(12), pp. 2815-2822), in this case it was used a very complex system of catalysts, as the CuI socialization si is the topic of [PdII(η3-allyl)Cl] 2that is the disadvantage of the method.

A known method for the synthesis of phenylethynyl derivatives of aromatic compounds with the substitution of the iodine molecules in phenylacetylene type Sonogashira using Cu(I) (Copper-Catalyzed Synthesis of 1,3-Enynes. Craig G. Bates, Pranorm Saejueng, and D. Venkataraman. Organic Letters, 2004, Vol.6, No.9, 1441-1444). When this system was used Cu(I) as the main catalyst (for example [Cu(bipy)PPh3Br]), Cs2CO3, toluene, 110°C, 24 hours. It is also a complex system, which is a disadvantage of the method.

Object of the invention is to develop an effective method of obtaining phenylethynyl derivatives of aromatic compounds with the substitution of the iodine molecules in phenylacetylene using copper nanopowder.

The copper nanopowder prepared by a known method of electrical explosion of wire in an atmosphere of inert gas argon (jaworowski N.A., ALEXANDER Pustovalov, Lobanov GL, Zhuravkov S. p. study of the properties of aluminum powders obtained in argon with the addition of oxygen. // Izvestiya vuzov. Physics. 2012, T, No. 6/2, p.236-244). To obtain copper nanopowder was used to install UDP-4G, copper wire mark "MM" diameter 0,25 mm Length of exploding for one pulse of the wire piece is 105 mm, the charging voltage U=21 kV, the capacity of the capacitor Bank C=2,24 cf. The pressure of argon in the installation of 2.5 ATM. For electroexplosive nanopowders synthesis methodology is, through the metal wire is passed pulse current density (1010A/m2), resulting in the conductor vzryvoobrazno destroyed, the products of the explosion are condensed in the atmosphere of inert gas to form nano-sized particles. The powder obtained in this way has a value of specific surface area Sbeats=8m2/g, which corresponds to the average particle size of 84 nm (the size of the agglomerates is about 150-300 nm), and has high chemical activity. A dark-brown powder. The particle shape is spherical. Bulk density of about 5 g/cm3. The powder contains metallic copper (Cu), about 98% wt.; the rest of sorbed gases, copper oxide CuO is less than 1%, Cu2O less than 1% and H2O.

It is known that the nanopowder copper reacts with phenylacetylene in dimethylformamide (DMF), forming a yellow precipitate complex diphenylbutadiyne and copper. (Copper and Copper Oxides Nanopowders in the Oxidative Condensations of Phenylacetylene and tert-Butylacetylene. O.A. Kuznetsova, E.F. Khmara, V.I. Filyakova, M.A. Uimin, A.E. Ermakovb, S. Kaliev Rheec, and V.N. Charushin. Zhurnal Obshchei Khimii, 2007, Vol.77, No. 3, pp.439-443. Nanopowders based on copper and its oxides in oxidizing condensation phenylacetylene and tert-butylaniline, O. A. Kuznetsov, E. F. Khmara, C. I. Filatova, M. A. Uimin, A. E. Ermakov, S. Kaliev Rhee, C. N. Charushin. Journal of General chemistry. 2007, T, issue 3, s-443).(Synthesis and crystal structure of tetranuclear nickel(0) complex with 1,4-diphenylbutadiyne in the η2, η2-bridging mode. aekawa, M., Munakata, M., Kuroda-Sowa, T., and Hachiya, K., Inorg.Chim.Acta, 1995, vol.231, p.213.) (Synthesis and crystal structure of unsymmetrical trinuclearnickel(0) complexes with the 1,3-butadiynes in the monodentate and µ2-η2, η2-bridgin mode [Ni3(L)(cod)3] (L=tmsb and dpbd) out by Maekawa, M., Munakata, M., Kuroda-Sowa, T., and Hachiya, K., Polyhedron, 1995, vol.14, p.2879).

This means that in DMF in the presence of nanopowder copper phenylacetylene can timeresults. But before the formation diphenylbutadiyne appear radical particles of the type phenylacetylene [PhC≡C].

Prepare a mixture of two catalysts - Cu nanopowder and CuI, the nanopowder Cu reacts with phenylacetylene to form a radical particle phenylacetylene, and simultaneously CuI reacts with odensala (arriagada), thus activating it. In the two transitional particles react with each other forming diphenylacetylene.

This object is achieved in that produce heating of the mixture components, 0.01 mol of phenylacetylene, 0.01 mol of odensala (aricidea), 0,0006 g copper nanopowder and 0.002 g CuI at a temperature of 110-120°C for 3 hours. After cooling the reaction mixture it is then poured into 100 ml of cold water with stirring, extracted with ethyl acetate. Then purified on a column of silica gel, elwira mixture solvent ethyl acetate : hexane in a ratio of 1:6. Next, the solvent is distilled off, getting friendly products. The mixture of reagents nano is orosco copper and CuI plays the role of catalyst, which reacts with the two substrates by the mechanism based on the reaction Sonogashira.

Thus, the proposed method allows to obtain phenylethynyl derivatives of aromatic compounds with the substitution of the iodine molecules in phenylacetylene using copper nanopowder. The method gives the yields of target products from 70 to 90%, significantly simplifies the process (see table).

Table
The method of obtaining phenylethynyl derivatives of aromatic compounds
SubstratesProductsYield, % (time)T C (p-l)/ %C %H
95 (0.5 hour)248-250°C (AcOBu) %C 94,92 %H a 4.83
90 (1 hour)188-190°C (Acoet) %C than 94.69 %H a 5.25
87 (2 hours) 155-156°C (AcOBu) %C 94,95 %H 4,75

85 (2 hours)338-341°C (AcOBu) %C 94,90 %H is 4.93
87 (2 hours)186-188°C (AcOBu) %C 90,82 %H 4,82 %O 4,32
82 (2.5 hour)242-244°C (AcOBu) %C 94,92 %H 4,85

75 (3 hours)253-254°C (Acoet)%C 94,91 %H 5,00
77 (3 hours)136-137°C (Acoet) %C 94,82 %H 5,15
72 (3 hours)176-178°C (Acoet) %C 94,96 %H 4,95
70 (3 hours)62-63°C (Eton) %C 94.34 %H 5.66

The method of obtaining phenylethynyl derivatives of aromatic compounds, comprising heating a mixture of components, 0.01 mol of phenylacetylene, 0.01 mol of odensala (arriagada), 0,0006 g copper nanopowder and 0.002 g CuI at a temperature of 110-120°C for 3 hours, after cooling the reaction mixture it is then poured into 100 ml of cold water with stirring, extracted with ethyl acetate, and then purified on a column of silica gel, elwira mixture solvent ethyl acetate : hexane in a ratio of 1:6, then the solvent is distilled off, getting friendly products.



 

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