AZ9RBAYCAN KIMYA JURNALI № 1 2017
67
UDC 541(64+515):542.952
SYNTHESIS OF COPOLYMERS OF 4(2)-FORMYL PHENYL METHACRYLATE WITH L-(-)-MENTHYL ACRYLATE
1O.B.Abdiyev, 2E.G.Mamedbeyli, 3I.M.Akhmedov
institute of Polymer Materials, NAS of Azerbaijan 2Yu.G.Mamedaliyev Institute of Petrochemical Processes, NAS of Azerbaijan
Baku State University
Received 18.02.2016
By a method of the radical copolymerization the carbonyl-containing optically active copolymers has been prepared. It has been shown that the copolymerization constants of 2-formyl phenyl methacrylate is lower than the corresponding 4-isomer which has been stipulated by steric hindrance created by formyl substituent in phenol nucleus. The optical activity of the synthesized copolymers has been determined.
Keywords: copolymerization, azeotropism, 4(2)-formyl phenyl(meth)acrylates, L-(—)-menthyl acrylate, optical activity, IR spectra, NMR 1H spectra.
Introduction
The aryl(meth)acrylate copolymers are used in the various branches: optically active compounds - as the adsorbent in splitting of P-lactames, aminocompounds, aminoacids, etc by chromatographic method to their enantiomers [1]; the others [2] show a high efficiency in division of oligonucleotides from their mixture with ami-noacid; their liquid-crystalline representatives can be used for preparation of layers with possibility of multiple record [3] and as materials for devices used in computer science [4]. Nitroderivatives of arylmethacrylates such as p-nitrophenylacrylate-co-N-isopropylate [5], etc. are used in preparation of "clever" hydrogels. In this connection the investigations in the field of study of kinetic
and other regularities of copolymerization of functional-containing aryl(meth)acrylates with various monomers are expanded. For example, it has been carried out the copolymerization of 4-methacryloyloxyazol with N-vinyl carbazole [6], S-(-)-[(nitrophenyl)pyrrolidine-2-yl]methyl-2-methacrylate with azobenzomethacrylate [7], formyl-containing aryl methacrylates with L-(-)-menthyl methacrylate (L-(-)-MtA) [8] etc.
In spite of this, the copolymerization of 4(2)-formyl phenyl (meth)acrylates (FPh(M)A) with L-(-)-MtA with preparation of 4(2)-FPhMA) with L-(-)-MtA has been not carried out.
This work has been devoted to the synthesis of new copolymers of formyl-containing arylmethacrylates with L-(-)-MtA:
r I
n ch2=c 2 I 0=c
o
r'' (I, II)
r'
+ m ch9=ch 2 I 0=c I
o
ch
BP
r I
■+ch2—c
2 I
0=c I
o
ch2—ch— 2 I 0=c I
o
r'' (III, IV)
r = ch3 , r' = h , r'' = cho (i); r = ch3 , r' = cho , r'' = h (ii); r = ch3, r1 = h, r2 = cho(iii); r = ch3, r1 = cho, r2 = h (iv).
ch
ch
n
2
Experimental
GLC has been carried out on chromatograph "LKHM-8MD", metallic column by size 300^0.3 cm; gas-bearer rate (He) - 40 ml/min, column temperature 452 K, evaporator -561 K. TLC analysis was carried out on adsorbent Silufol UV-254; as an eluent it was used acetone, dioxane, methylethyl ketone, ethyl acetate, etc, and also their mixture in various ratios: for example, dioxane:benzene = 4:1, methyl ethyl ketone:dioxane = 2:1, ethyl ace-tate:acetone =3: 1 etc. Developer - iodine pairs.
NMR 1H spectra were registered on apparatus "BruKer WP-400" ('H 400 MHz, internal standard - tetramethyl silane), the IR-spectra were taken on apparatus UR-20, optical activity - on polarimeter SM-2. For determination of optical
activity [a]^5 there were made the solutions of
optically active compounds, the concentration of which was 10 g substance in 100 ml of chloroform solution. The polarimeter tubes by length 0.1 m were filled with this solution and were placed them in polarimeter SM-2.
4(2)-Formyl phenyl methacrylates have been synthesized by the reaction of chloranhydride of methacrylic acid with acetyl phenol; 4-formyl phenyl methacrylates (4-FPhMA) according to the method [8], and L-(-)-MtA - according to the method [9].
The monomers directly before polymerization were purified from inhibitor and impurities distillation in vacuum in the presence of copper monochloride in atmosphere of dry pure nitrogen, benzoyl peroxide (BP) recrystallization from solution in diethyl ether, the methanol was purified by distillation.
For determination of copolymerization constants the process was carried out in ampoules at 800C in absolute dioxane to small degree of conversion (6-11) % in atmosphere of dry pure nitrogen at various molar ratios of monomers with their total concentration of 2.5 mol/l (Table 1). As an initiator it was used 0.09 mol. % BP from total quantity of monomers. The prepared copolymers three times were purified by precipitation in methanol firstly from solution in dioxane and then in chloroform. After filtration the copolymers were dried in vacuum at 400C to constant mass. The synthesized polymers -amorphous powders of white color.
Results and discussion
On the basis of composition of copolymers (Table 1) there have been calculated x and y
f
f^* V
x =
V M2 J
m
m
У =
M
M.,
m
-1
V m2
the va-
JJ
lues of which are presented in Table 1.
Table 1. Composition, optical activity and x, y copolymers of 4(2)-FPhMA
MJ with L-(-)-MtA [M2]
Composition of initial mixture of monomers, mol.% Composition of copolymers, mol.% C, % X y №, 0.1M CHCI3 Quantity of 4(2)-FPhMA in copolymer, g
Mj M2, m1, m2,
4 -FPhMA-co -L -(-) -MtA
10 90 14.31 85.69 73.61 0.072 -0.55 670 0.868
30 70 37.5 62.5 72.56 0.31 -0.29 50 0.64
50 50 56.9 43.2 71.64 0.76 0.25 35.2 0.456
70 30 76.68 23.32 66.98 1.65 1.62 14.2 0.183
80 20 83.14 16.86 70.47 3.2 3.2 19.4 0.251
2 -FPhMA-co -L -(-) -MtA
10 90 12.96 87 73.72 0.081 -0.63 67.90 0.88
30 70 31.5 68.49 72.84 0.4 -0.5 54.40 0.705
50 50 54 45.6 71.78 0.84 0.156 37.10 0.48
70 30 61.83 38.17 71.4 2.1 1.43 31.30 0.4
80 20 81.2 18.83 70.45 3.7 3.06 15.4 0.2
As is seen from data of Table 1 all prepared copolymers - optically active.
The structure of the prepared copolymers has been proved by IR and NMR H spectroscopy, polarimeter method and elementary analysis. In the IR spectrum there have been detected the absorption bands (cm-1): 15801605, 3032-3050 (arom.), 1655-1688 (-C=O), 1713-1730 (COO-), 2945 (-CH2), 1370-1384 (-CH3), 850-1038 (menthyl), 2785 CH in CHO.
In the NMR 1H spectrum of copolymer of 4-FPhMA with L-(-)-MtA there are appeared the following signals of protons (CDCl3, 5, ppm):
0.8 m (
ch-
-c(ch3 ), 1.23-1.4 m (5H, CH3,
i ch3
h._
CH2), 1.54 m (3H, V^o- ), 1.69-1.90 m
w
\
-ch,
( h^ > o- ), 2.35 s (1H, HC-COO), 4.87 s
ch,-
(1H, <0<° ), 7.16 m (2H, _
), 9.14 s (1 H, CHO).
), 7.95 m
(2H,
Similarly NMR 1H spectrum of the rest copolymers corresponds to structures (IV).
Using the x and y values there have been determined the copolymerization constants by method [10].
Table 2. Copolymerization constants of 4(2)-FPhMA (M1) and L-(-)-MtA (M2)
M1 M2 r1 r2 r^2
4-FPhMA L-(-)-MtA 1.18 0.64 0.75
2- FPhMA L-(-)-MtA 1.02 0.72 0.73
It follows from Table 2 that the copolymerization constant values of aryl methacry-lates are larger than menthyl acrylate (ri > r2) and the copolymer is enriched by 4(2)-FPhMA-links. The high activity of 4(2)-FPhMA, in comparison with L-(-)-MtA, can be explained by large electron-acceptor of formyl phenyl groups, in comparison with menthyl ones. As in molecule of FPhMA between formyl phenyl and acryloyl fragments through genuine electron pair
of oxygen bridge there is n-n conjugation due to of which a double bond of acryloyl fragment of FPhMA is polarized strongly than a double bond of L-(-)-MtA. Consequently, FPhMA possesses greater reactivity in comparison with L-(-)-MtA.
It follows from Table 2 that the copo-lymerization constants of monomers 4(2)-FPhMA differing between themselves by 2- or 4-position of substiuents in benzene nucleus are also differed, 4-FPhMA possess more high relative activity in comparison with 2-FPhMA. This has been stipulated by that the formyl substituents in benzene nucleus being in 2-position in relation to methacrylic group, create definite steric hindrances of addition.
It is seen from Figure 1 that the curves of dependence of monomer composition of co-polymers on initial monomer compositions are only on one side of regression line. In prepared copolymers the monomer links have been located disorderly - copolymer is static. It has been revealed from Table 2 that at r1>1, r2< 1 a content of 4(2)-FPhMA-links in macromole-cules is higher than L-(-)-MtA-links. In figure there are not points belonging to both co-polymer composition and composition of initial monomer links, in other words in copolymers of 4(2)-FPhMA-L-(-)-MtA, 2-FPhMA-L-(-)-MtA there is not an azeotropism.
Mi,mol%
Fig. 1. Dependence of copolymers composition on composition of monomers mixture at copolymerization L-(-)-MTA with 4-FPhMA (1), 2-FPhMA (2).
H
In all cases r1-r2< 1 and in copolymers there is a tendency to alternation of monomer links.
The character of dependence of specific rotation of plane of the light polarization in solution on quantity of optically active monomer in the copolymer has been studied. This is important in the sense that there are conflicting data in the literature about character of
dependence [a]2^ on amount of optically active
monomer: a number of authors as a result of the carried out investigations have concluded [11],
that in a series of copolymers [a]^6 is changed
proportionally changes of amount of optically active monomers in the copolymer, while as one can make a conclusion from investigations of a number of other authors in this direction that this confirmation is not always true. For ex., Beredjik [12], studying the copolymerization of L-a-methyl benzyl methacrylate with maleic anhydride, have detected that the forming copolymer after detachment from side chain of optically active L-a-methyl benzyl group retains
an optical activity ([a]^5 = +0.22, M¿5 = +33.20 (l
= 0.05 m, C = 2.2 % in dioxane)). This means that an optical activity of the prepared copolymers will also not proportionally depend on content of optically active monomer links in the indicated copolymers.
The above-mentioned and other literature data devoted to this subject show that the rules exactly predicted the character of dependence of optical activity on content of optically active groups in the copolymer is not found yet. For solution of this problem it is necessary the carrying out of careful investigations, one of which is this work.
In Figure 2 it has been shown the linear dependence of specific rotation ([a £) 4-FPhMA-
co-L-(-)-MtA on mass fraction of L-(-)-MtA. It has been also revealed that the optical activity of the rest copolymers similarly depends on content of L-(-)-MtA and the composition of such copolymers can be determined on value of their optical activity.
Mass fraction of L-(-)-MtA in copolymer
Fig. 2. Dependence of optical activity of 4-FPhMA (2) and 2-FPhMA (1) with-L-(-)-MTA on content of L-(-)-MTA in the copolymer.
Conclusions
1. The copolymerization of 4(2)-FPhMA with L-(-)-MtA has been studied. It has been shown that the relative activity of 4-FPhMA is greater than 2-FPhMA and copolymer has been enriched by 4-FPhMA-links.
2. It has been revealed that during polymerization of 4-FPhMA with L-(-)-MtA there is a tendency to alternation. The prepared copolymers are statistical.
3. There have been synthesized the new acetyl-containing optically active copoly-mers, an optical activity of which proportionally rises with increase of amount of L-(-)-MtA in the macromolecule. A composition of such copolymers can be determined on value of their optical activity.
References
1. Pat. 3706890 A1 ADR. Optisch (meth)acrylamide, Verfahren zur ihrer herstellung und ihre Verwendung zur Racemaspaltung / Börner B., Crosser R. 1988.
2. Bisjak C.P., Trojer Y., Lubbad S.H., Wider W. Influence of different polymerization parameters diacrylate capilliary columns // Chromatoqraphia. A. 2007. V. 1154. No 1-2. P. 269-273.
3. Шибаев В.П. Жидкокристаллические полимеры: Прошлое, настоящее и будущее // Высокомолек. соед. A. 2009. T. 51. № 11. C. 1894-1929.
4. Шибаев П.В., Войко Н.И., Бобровский А.Ю.,
Шибаев В.П. Генерация лазерного излучения полимерных холистерических сетках // Высо-комолек. соед. А. 2005. T. 47. C. 961-969.
5. Guerrero-Ramirer L.C., Katime I. Intellectual hydrogels: Synthesis, Characterization and Properties // Mater. Chem. and Phys. 2002. V. 112. No 3. P.1088-1092.
6. Altomare A., Ciaredelli F., Mellini L., Solaro R. Photoactive azobenzene polymers containing carbazole chromophores // Macromol. Chem. and Phys. 2004. V. 205. No 12. P. 1611-1619.
7. Sonia Z., Erwelina O., Redis B., Law K. Preparation and characteristics of new chiral pho-tochromatic copolymers // Opt. Mater., 2009. V. 32. No 1. P. 198-206.
8. Abdiyev O.B. o- va ^-Formilfenilmetakrilatlann l-(-)-mentilmetakrilatla radikal sopolimerbijmabri
// Azarb. kimya jurn. 2006. № 1. P. 157-161.
9. Мамедов Э.Г. Асимметрическая реакция Дильса-Альдера С4-С6 сопряженных диенов с активированными диенофилами. Дисс. ... докт. хим. наук. Баку: ИНХП, 2003. 336 с.
10. Vijyaraghavan P.G., Reddy B.S.R. Synthesis, Characteristics, Reactivity Ratios by Nuclear Magnetic Resonance Spectroscopy and application of (2,5-Dichlorophenyl acrylate-co-glysidyl methacrylate) Polymers as Adhesives for the Leather Industry // J. Appl. Polym. Sci. 2006. V. 99. P. 1167-1174.
11. Schulz R.C. Optisch aktive syntetische polymere // Kolloid Z. und Polymere. 1964. V. 197. No 1-2. S. 55-58.
12. Beredjick N. Stereospecific Vinyl Polymerization by Asymmetric Induction // J. Am. Chem. Soc. 1958. V. 80. P. 1933-1938.
4(2)FORMiLFENiLMETAKRiLATALRIN L-(-)-MENTiLAKRiLATLA BiRGOPOLiMERLORlN
SiNTEZi
O.B.Abdiyev, E.Q.Mammadbayli, LM.Ohmadov
4(2)-Formilfemlmetakrilatlarm L-(-)-metakrilatla radikal birgapolimerla§malari üsulu ila yeni karboniltarkibli birgapolimerlar alinmi§dir. Göstarilmi§dir ki, 4(2)-formilfenilmetakrilatlar L-(-)-mentilakrilata, 4-formilfenilmetakrilat 2-formilfenilmetakrilata nisbatan yüksak birgapolimerla§ma sabitina malikdir.
Agar sözlar: birgapolimerlaqma, azeotropluq, 4(2)-formilfenilmetakrilat, L-(-)-mentilakrilat, optiki aktivlik, iQ spektr, NMR 'H spektr.
СИНТЕЗ СОПОЛИМЕРОВ 4(2)-ФОРМИЛФЕНИЛМЕТАКРИЛАТА С L-(-)-МЕНТИЛМЕТАКРИЛАТОМ
О.Б.Абдыев, Э.Г.Мамедбейли, И.М.Ахмедов
Радикальной сополимеризацией 4(2)-формилфенилметакрилата с Ь-(-)-ментилакрилатом синтезированы новые карбонилсодержащие сополимеры. Обнаружено, что значения констант сополимеризации 4(2)-формил-фенилметакрилатов больше, чем Ь-(-)-ментилакрилата, а их значения для 4-формилфенилметакрилата выше по отношению к 2-формилфенилакрилату. Выявлены причины проявления вышеуказанных выводов.
Ключевые слова: сополимеризация, азеотропность, 4(2)-формилфенилметакрилат, Ь-(-)-ментилакрилат, оптическая активность, ИК-спектр, спектр ЯМР И.