.

5.

A. S. Kireev, Practical Calculation Methods in the Thermodynamics of Chemical Reactions [in Russian], Khimiya (1970). U. D. Veryatin, V. P. Mashirov, N. G. Ryabtsev, V. I. Tarasov, B. D. Rogozkin, and I. V. Korobov, Thermodynamic Properties of Inorganic Compounds [in Russian], Atomizdat, (1965).

OLIGO~RIC ORGANOSILICON DICYANO ETHERS

V. V. Korshak, M. M. Patsuriya, V. A, Pankratov, S. V. Vinogradova, L. I. Makarova, and K. A. Andrianov

UDC 541.64:547.1'128

Information is absent in the literature on dicyano ethers that contain flexible silox- ane fragments between the cyanatophenyl groups. Such compounds are of great interest as a base for the synthesis of various heat-resistant polymers that have low glass transition temperatures. Regular crosslinked polymers are formed when such monomers are polymerized due to the high selectivity of the cyclotrimerization of the cyanate groups, the mol. wt. of which monomers is preset by the size of the radical between the cyanatophenyl groups. In turn, this makes it possible to knowingly control the properties of the polymers based on them.

We developed [i] a method for the synthesis of dicyanates that contain a variable number of siloxane groups, which differ in the organic framework around the silicon atom, between the cyanatophenyl groups. The dicyano ethers were obtained by the acylation of organosili- con bisphanols [2] with a cyanogen halide in the presence of a tertiary amine by the follow- ing scheme:

m ,,y xX " , , ~ / / \

HO

CH~ CH3 CH3 - \ j ] [ I / - \

0CH~Si--(0Si)n--0SiCH~O OH ~ 2CtCN .... 2N(Et), l I [ --2(Et)s:4.HC~

CH~ R CH~ / /--K / S - ~

CH~ CH3 CH~ ~ / / \ I l I / \

NCO OCH~Si--(OSi)a--OSiCH..O OCN t i ]

CH3 R CH3 n=0--i00 whenR=CH~ n=i--10 whenR=C6H~.

As a result we synthesized 12 organosilicon dicyano ethers in practically quantitative yields (92-98%). For the most part these dicyano ethers are either colorless or pale yellow oily compounds [except for bis(2-cyanatophenoxymethyl)tetramethyldisiloxane, n = 0, which is crystalline and has melting point 44.2-44.8~ [3]]. The dicyano ethers were identified via elemental analysis, the IR and N~ spectra, and also by the molecular refractions.

When the NMR spectra of the bisphenol and the corresponding dicyano ether were compared it was found that the comparative integral intensity of the protons of the methyl (0.225 ppm) and methylene (3.57 ppm) groups remains approximately the same for both products. The main difference in the spectra was the absence of the signal of the hydroxyl groups (5.5 ppm) for the dicyanate and the splitting of the singlet of the protons of the benzene ring (6.6 ppm) into a multiplet when the hydroxyl protons are replaced by CN groups.

Institute of Heteroorganic Compounds, Academy of Sciences of the USSR, Moscow. Trans- lated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2803-2806, Decem- ber, 1976. Original article submitted March 30, 1976.

This material is protected by copyright registered in the name o f Plenum Publishing Corporation, 227 West 1 7th Street, New York, IV. Y. 10011. No part o f this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, wi thout written permission o f the publisher. A copy o f this article is available f rom the publisher for $Z50.

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TABLE I.

Number of si- loxane units

0

t

5

t0

25

40

50

70

t00

Oligomeric Organosilicon Dicyanates

2--% / CHa CHa CHs X,~_~/

/ \ I 1 I / \ NCO OCH~Si--(O--Si)n--OSiCH20 OCN

CH~ R CHa

r Found Calculated %

Found Calculated' %

I H ] Si

t,4975

i,47f0

1,4409

1,4270

t,4tt2

t,4t00

t,4090

1,4080

Dimethylsiloxane dicyanates (R---- CH3)

1,1296

i,o527

t,0381

1,0270

�9 0,9934

0,9771

0,9744

0,9723

t51,85 153,76 2t0,09 212,73 3i9,62

553,02 557,46 846,61 843,90

t035,30 1041,86 1420,28 1417,78 198t,32 t987,ti

55,97 56,04 52,6i 52,55 51,29 5t,42 4t,C~ 4t,02 36,62 36,84 34,99 35,29 34,7~ 34,81 34,22 34,19 33,59 33,68

5,56 5,60 6,02 5,97 7,68 7,7t 7,03 7,18 7,87 7,63 . 7,68 7,76 7,89 7,79 7,87 7,91 8,00

13;27

16,43 i6,78 27,93 28,00 27,94 28,80 33,50 33,24 34,32 34,70 36,05 ~5,35 36,40 36,28 36,60 3~,5~

3

5

i0

1,5423

t,5490

1,5460

Methylphenylsiloxane dicyanates (R= CsHs)

t,0647

1,0633

1,0525

249,67 248,35 331,88 333,2t 538,71 536,99

58,71 59,50 59,49 60,00 59,07 60,70

6,26 6,36 6,29 6,23 6,0t 6,09

t7,90 16,27 18,07 18,58 19,33 t9,38

Absorption bands in the 2275-2245-cm -x region were observed in the IR spectra of the dicyano ethers, which are characteristic for the stretching vibrations of O-CEN groups [4], whose intensity decreases with increase in the length of the siloxane chain between the cya- natophenyl radicals. In contrast to the starting bisphenol, absorption bands in the 3450- 3550 cm -~ region, which correspond to the vibrations of hydroxyl groups, are completely ab- sent in the IR spectra of the dicyanates, which testifies to the complete replacement of the hydroxyl protons by nitrile groups. Some of the characteristics of the organosilicon dicya- nates are given in Table I. From the given data it can be seen that the found values of the molecular refraction and the results of the elemental composition agree well with the theoretically calculated values. The obtained organosilicon dicyanates can be used as a base to synthesize polycyanates with low glass transition temperatures and a high heat re-

sistance.

EXPERIMENTAL

Bis(2-cyanatophenoxymethyl)hexamethyltrisiloxane? With vigorous stirring and cooling to--10 ~ a solution of 16.8 g (0.168 mole) of triethylamine in i0 ml of acetone was added dropwise to a solution of 18.31 g (0.041 mole) of bis(hydroxyphenoxymethyl)hexamethyltrisi- loxane and 5.09 g (0.083 mole) of cyanogen chloride in 25 ml of dry acetone in such manner that the temperature of the reaction mixture did not exceed 5 ~ . When all of the triethyl- amine had been added the reaction mass was kept at 0 ~ for 15 min, after which it was poured

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into ice water, i00 ml of benzene was added, and the organic layer was washed several times with ice water. The benzene solution was separated and the solvent was distilled off at 20 ~ in vacuo. We obtained 18.1 g (98%) of the dicyanate as a pale yellow oily liquid.

The other organosilicon dicyanates listed in Table 1 were obtained in a similar manner.

CONCLUSIONS

We synthesized and characterized some oligomeric organosilicon dicyano ethers that offer promise as monomers for the preparation of heat'resistant polymers.

i.

2.

3,

.

LITERATURE CITED

K. A. Andrianov, V. V. Korshak, V. A. Pankratov, S. V. Vinogradova, M. M. Patsuriya~ L. I. Makarova, Ts. A. Goguadze, and L. M. Mitina, USSR Patent 496,292 (1974); Byull. Izobr., No. 47, 64 (1975). K. A. Andrianov, V. V. Korshak, M. M. Patsuriya, V. A. Pankratov, L. I. Makarova, S. V. Vinogradova, Ts. A. Goguadze, and L. M. Mitina, Izv. Akad. Nauk SSSR, Ser. Khim., 1975, 1671. K. A. Andrianov, V. A. Pankratov, M. M. Patsuriya, L. I. Makarova, V. V. Korshak, S~ V. Vinogradova, N. G. Bekauri, Ts. A. Goguadze, and L. I. Mitina, Izv. Akad. Nauk SSSR, Ser. Khim~ 1975, 61. E. Grigat and R. Putter, Chem. Ber., 98, 1168 (1965).

THE~IODYNA~IIC CHARACTERISTICS OF DISSOLVING SOME ALKYLTIN HALIDES

A. N. Korol, V. A. Chernoplakova, UDC 536.7:542.61:547.258.11v121 K. I. Sakodynskii, and K. A. Kocheshkov

The compounds R3SnX represent interest as intermediates in various kinds of syntheses and when studying the structure of organotin compounds. Derivatives of this class find prac- tical use as physiologically active substances, anthelminthics, components of antifungal pigments, etc. [i]. However, methods for identifying these compounds have not been devel- oped, the character of the intermolecular reaction when separation is in solvents of variable polarity has not been studied, and the gas chromatography studies are disconnected [2].

The object of the present paper was to determine the molar heats and entropies of dis- solving alkyltin halides (ATH) in stationary phases of variable nature, and also the rules that relate these thermodynamic functions to the properties of the molecules of the compounds being separated.

EXPERIMENTAL

A Tsvet-4 chromatograph, equipped with a detector based on the heat conductivity, and a 1 m • 3 mm column were used. The stationary phase (2% Apiezon L and 0.1% Siloxane Elasto mer 0F-1.5% XE-60) was deposited on silanized Chromosorb G (80-100 mesh). The temperature of the batcher was 30~ higher than the column temverature. The flow rate of the carrier gas (helium) was 40 ml/min. The studied compounds were added to the column with a lO-~liter microsyringe. Since the retention time depends on the amount of sample a fixed amount of sample was added, either 0.4 or 0.9 vliter, n-Tridecane was taken as the standard when Apiezon L was used (140-172~, and dibenzyl (158-190 ~ ) and naphthalene (116-140 ~ ) when XE-60 was used. The molar heats of solution were calculated using the function: temperature vs

L. Ya. Karpov Physicochemical Institute, Moscow. Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2806-2809, December, 1976. Original article submitted April 16, 1976.

This material is protected by copyright registered in the name o f Plenum Publishing Corporation, 227 West 1 7th Street, New York, N. Y. 10011. No part o f this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, elec tronic, mechanical, photocopying, microfilming, recording or otherwise, wi thout written permission o f the publisher. A copy o f this article is available f rom the publisher for $ Z SO.

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