Химико биологическая серия 1 2014
ISSN 1811-184X. Вестник ПГУ
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- ISSN 1811-184X. Вестник ПГУ серия ХИМИКО - БИОЛОГИЧЕСКАЯ. 2014. № 1 20 21
- Нурахметов, Н. Н.
- Нурахметов, Н. Н., беремжанов, б. а.
- Liber, M., Marcovic, D.
| ISSN 1811-184X. Вестник ПГУ
серия ХИМИКО - БИОЛОГИЧЕСКАЯ. 2014. № 1 18 19 extended and a length of C=O bond is shortened. Thus, in the above-mentioned cases, presumably proton completely goes into disposition of amine nitrogen of acetamide. Confirmation of this is, for example, sufficiently considerable distance between the proton (H + ) and the oxygen atom of the hydroxyl group of nitric acid (0,3484 nm) (table 1). Comparative analysis of the length of the O a -Me shows the dependence of the change in its value from the process of protonation of the amide. In compounds in which the proton is almost completely moved to acetamide difference of change of this characteristic is significant: 0,4027, 0,4189 and 0,0034 nm for ZnBr 2 ·CH
3 CONH
2 ·HBr, Zn (NO 3 )
·CH 3 CONH 2 ·HNO
3 and Be
(NO 3 ) 2 ·CH
3 CONH
2 ·HNO
3 , respectively. Geometrical parameters of complex compounds Me-O of zinc salts and beryllium with unprotonated acetamide (1:1) and with protonated (1: 1: 1) are shown in tables 2 and 3. Table 2 – Geometrical parameters of complex compounds Me-O of zinc salts and beryllium with unprotonated acetamide (1:1), grad. Compounds Parameters ZnBr
2 ·CH
3 CONH
2 Zn(NO
3 ) 2 ·CH 3 CONH 2 ВеBr
2 ·CH
3 CONH
2 Ве(NO
3 ) 2 ·CH 3 CONH 2 ∠ O–C–N 113,44 121,01
117,39 117,32
∠ O–C–С
124,51 118,41
119,74 120,86
∠ C–N–H
119,92 121,80
122,93 119,04
117,32 126,12
116,54 121,98
∠ C– С– N
122,05 120,58
122,87 121,74
∠ C–С–H
110,37 113,86
110,37 113,19
110,55 110,52
113,12 110,42
110,42 110,23
112,02 111,64
∠ H –С–H
106,13 107,88
107,88 107,67
106,98 107,68
107,83 106,97
107,83 107,17
107,67 ∠ H – N–H 118,29 117,98
116,56 115,30
∠ C–О–Ме
117,21 124,98
115,82 106,95
∠ Cl (Br, O к. ост
)- –Ме –О
а 111,87
122,69 104,50
113,50 133,26
106,65 114,18
113,03 Table 3 – Geometrical parameters of complex compounds Me-O of zinc salts and beryllium with protonated acetamide (1: 1: 1) Compounds Parameters ZnBr
2 ·CH
3 CONH
2 ·HBr
Zn(NO 3 ) 2 ·CH
3 CONH
2 · НNO 3 ВеBr
2 ·CH
3 CONH
2 · HBr Ве(NO 3 ) 2 ·CH
3 CONH
2 · НNO 3 ∠ O–C–N 115,14 117,25
116,74 112,96
∠ O–C–С
128,50 125,25
120,94 122,14
∠ C–N–H
108,48 111,71
113,17 111,14
118,58 124,87
110,34 106,44
∠ C– С– N
116,36 117,39
116,75 119,65
∠ C–С–H
111,36 111,25
111,06 110,74
111,53 111,45
112,51 111,10
110,25 111,17
109,94 112,66
∠ H –С–H
107,71 107,52
107,76 107,91
107,54 107,48
108,01 107,24
107,52 108,06
107,26 107,54
∠ H – N–H
108,89 110,68
116,28 109,02
∠ C–О
а –Ме
37,63 133,70
107,26 112,28
∠ Cl (Br, O к. ост
)– Ме – О
а 53,18
169,92 108,59
107,66 105,04
117,70 117,09
105,31 ∠ C–N–H + 109,78
106,79 89,58
112,79 ∠ N–H + –ост.кисл. 170,47 173,92
48,81 102,03
∠ Cl (Br, O к. ост
) – Ме –Cl (Br, O к. ост
134,06
141,55 134,99
133,44 Comparison of the results the calculation of the angular characteristics for investigated amides allows you to make following conclusion (tables 2 and 3). As a result of protonation are observed slight changes in the values of the valence angles, but in good agreement with the change of the interatomic distances in the molecules of complexes of metal salts; they also depend on the steric factor, as the case with compounds containing more complicated on spatial structure of an inorganic acid - nitric. Analysis of values of the valence angle ∠ O-C-C for the compounds of zinc and beryllium shows that protonation of the compounds according to the nitrogen atom of amino group of the acetamide leads to a considerable increase of the characteristics in comparison to the parent molecule. Most significantly increased angle
∠ O-C-C in the case of protonation Zn(NO 3 )
·CH 3 CONH 2 - the difference is 6,84°, in that case the highest value of this angle is observed in molecule Zn(NO
3 ) 2 ·CH 3 CONH 2 ·HNO
3 (128,50 °). Due to the fact that protonation occurs at the amino nitrogen atom of the acetamide, while amide molecule coordinated to the central atom of the complex – the metal atom by the carbonyl oxygen atom, quite naturally occur significant changes in the values of valence angles, containing a protonated nitrogen atom, namely: ∠ C-N-H,
∠ C-C-N and ∠ H-N-H. There is a difference in the direction of change of these characteristics when comparing the geometric parameters for salts of zinc and beryllium, ie, depending on the electronic nature of the central atom of zinc or beryllium. Comparison of the values of the angle H-N-H for the protonated and unprotonated acetamide complexes of zinc and beryllium shows an existence of trend towards lowering of these values. Among zinc salts greatest difference of change of this setting belongs to the complex zinc compound, protonated by hydrobromic acid – 9,4°, and among beryllium salts – by nitric acid – 6,28°. In that case the greatest angle H-N-H ISSN 1811-184X. Вестник ПГУ серия ХИМИКО - БИОЛОГИЧЕСКАЯ. 2014. № 1 20 21 are characteristic in the case of protonation by hydrohalic acids and the least upon protonation of the researching complexes of nitric acid. Thus, in the work using the quantum-chemical semiempirical calculation by the PM3 method, determined the geometric parameters of the protonated and unprotonated amide compounds and found some changes in the structure of the compounds. Semiempirical quantum-chemical method PM3 permitted to evaluate geometric parameters taken for the study of model molecules of complex compounds of zinc salts and beryllium with different molar ratio of acetamide. Method allowed to see the impact of different by electronic nature of inorganic acids, that proceed protonation on the structure of acetamide. Comparative analysis of the geometrical parameters showed the mutual influence of different by electronic and spatial nature of atoms and molecules included in the studied complexes. Based on the described above, clear to see that protonation of the nitrogen atom of amino group molecules of acetamide has a significant influence on changing of all the geometric characteristics of the researching compounds. LIST OF REFERENCES 1 Нурахметов, Н. Н. Амидкислоты. Итоги науки и техники. – ВИНИТИ. сер. Физ. химия. – 1989. – Т.4. – 64 с. 2 еркасов, р. Ш. Физико-химические основы синтеза и свойства соединений неорганических кислот с производными ацетамида, перспективы их применения : Дис. … д-ра хим. наук. – Воронеж – 1992. – 384 с. 3 Нурахметов, Н. Н., беремжанов, б. а. О взаимодействии неорганических кислот с амидами // Ж. неорг. химии. – 1978. – 23. – №2. – С.504-513 4 Нурахметов, Н. Н., еркасов, р. Ш., Ташенов, а. к. и др. Синтез и физико-химические свойства соединений неорганических кислот с амидами // КазГУ. – Деп.рук. в ВИНИТИ №575-82. – 1982. – 5 с. 5 Органическая химия В.Л. Белобородов, С.Э. Зурабян, А.П. Лузин, Н.А. Тюкавкина; под ред. Н.А. Тюкавкиной. – М. : Дрофа, 2004. – Кн. 1: Основной курс. – 640 с. 6 Liber, M., Marcovic, D. The temperature variation of the H A acidity function for sulphuric acid the thermodynamics if protonation of amids // J.Chem. soc. Perkin trans., 1982, №5, P.551-558 *L. N. Gumilev Eurasion National university, Astana; **S. Toraighyrov PSU, Pavlodar; ***Sh. Ualikhanov Kokshetau state university, Kokshetau. Material received on 03.03.2014.
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