New approach to the synthesis of linear and cyclic vinyl(alkoxy)siloxanes

Article abstract of DOI:10.1134/S1070363217060068

Main products of the reaction of vinyltrichlorosilane VinSiCl₃ with DMSO in the medium of tetra-(alkoxy)silane are linear siloxanes (RO)₃Si[OSiVin(OR)]OSi(OR)₃, RO[Vin(RO)SiO]_nSi(OR)₃ (R = Me, Et, n = 0–2) and the hitherto unknown cyclic siloxanes [Vin(RO)SiO]_m[(RO)₂SiO]_4–m (m = 1–3) formed in the ratio of 70: 30%. A tentative scheme of their formation is suggested with participation of the products of the alkoxy groups exchange between vinyl(alkoxy)dichloro-, vinyldi(alkoxy)chloro-, trialkoxychloro-, and dialkoxydichlorosilanes.

Full text of DOI:10.1134/S1070363217060068

ISSN 1070-3632, Russian Journal of General Chemistry, 2017, Vol. 87, No. 6, pp. 1137–1142. © Pleiades Publishing, Ltd., 2017.
Original Russian Text © S.V. Basenko, A.A. Mailyan, 2017, published in Zhurnal Obshchei Khimii, 2017, Vol. 87, No. 6, pp. 915–920.
New Approach to the Synthesis
of Linear and Cyclic Vinyl(alkoxy)siloxanes
S. V. Basenko* and A. A. Mailyan
Favorskii Irkutsk Institute of Chemistry, Siberian Branch, Russian Academy of Sciences,
ul. Favorskogo 1, Irkutsk, 664033 Russia
*e-mail: sv_basenko@irioch.irk.ru
Received March 23, 2017
Abstract—Main products of the reaction of vinyltrichlorosilane VinSiCl3 with DMSO in the medium of tetra-
(alkoxy)silane are linear siloxanes (RO)3Si[OSiVin(OR)]OSi(OR)3, RO[Vin(RO)SiO]nSi(OR)3 (R = Me, Et,
n = 0–2) and the hitherto unknown cyclic siloxanes [Vin(RO)SiO]m[(RO)2SiO]4–m (m = 1–3) formed in the ratio
of 70 : 30%. A tentative scheme of their formation is suggested with participation of the products of the alkoxy
groups exchange between vinyl(alkoxy)dichloro-, vinyldi(alkoxy)chloro-, trialkoxychloro-, and dialkoxy-
dichlorosilanes.
Keywords: vinyltrichlorosilane, alkoxychlorosilanes, dimethyl sulfoxide, silanones, vinyl(alkoxy)cyclosiloxanes
DOI: 10.1134/S1070363217060068
Alkoxysilanes are used as the main materials in sol–
gel processes in inorganic and organic chemistry [1],
surface modifiers [2], for protection of hydroxy groups
[3], and in cross-coupling reactions [4–5].
halosilanes with DMSO in different media [11, 18] we
have studied transformations of vinyltrichlorosilane in
tetraalkoxysilane media, Si(OR)4, R = Me, Et. We
believed that the use of organylhalosilanes with func-
tional groups Si–Cl and Si–Vin would allow to elaborate
an approach to the synthesis of new difficultly accessible
monomers containing alkoxy groups, along with the
aforementioned ones. Indeed, the reaction of VinSiCl3
with DMSO in tetramethoxysilane (molar ratio 1 : 1 : 1)
leads to the formation of 1-chloro-1-vinyl-1,3,3,3-
tetramethoxydisiloxane 1 in up to 10% yield.
Insertion of diorganylsilanones into the Si–X bonds
(X = H, O, Cl) is an indirect method of detection of
their participation in reactions [6]. Especially con-
venient as silanone traps are compounds containing
alkoxy groups [7, 8], in particular, methoxy group [9,
10]. Continuing our studies of the reactions of organyl-
Si(OMe)4
VinSiCl3 + Me2SO
Vin(MeO)ClSiOSi(OMe)3 + ClCH2SMe
(1)
_HCl
1
fragments [M – MeO – C2H4]+ are lacking for
cyclomethoxysilanes, and fragments [M – EtOH]+ are
present for cycloethoxysilanes. The cal-culated ratio of
the linear and cyclic siloxanes is 68 : 32% [Eq. (2)].
The formation of siloxane 1 is consistent with the
possibility of insertion of organylsilanones in the
molecule of hexamethyldisiloxane that we have shown
earlier [13]. However, the main products of the reaction
were found to be linear 2–4 and cyclic siloxanes 5–7 in
a total yield up to 80%. The ratio of the linear and
cyclic siloxanes was determined from the total
intensity of the corresponding peaks on GC. Chromato-
grams obtained by the GC and GC-MS methods coincide.
The assignment of peaks in GC-MS was based on their
characteristic fragmentation in mass spectra (Table 1):
The obtained results prompted us to perform the
monitoring of the process using the methods of GC-
MS and NMR spectroscopy for more detailed inves-
tigation of the studied reactions. Based on the GC-MS
and NMR 29Si data, we have found that after addition
of as small as 1–5% of DMSO the exchange of the
1137

1138
BASENKO, MAILYAN
Table 1. Principal characteristic ions in mass spectra of linear (5, 6)and cyclic (7–10) vinyl(methoxy)siloxanes
m/z (Irel, %)
Ion
5
6
7
8
9
10
[M – Vin]+
[M – MeO]+
[M – MeOH]+·
[M – Vin – CH2O]+
393 (60)
389 (29)
388 (33)
363 (17)
361 (3)
347 (100)
333 (19)
–
389 (100)
385 (18)
384 (24)
359 (22)
357 (11)
343 (63)
329 (17)
317 (19)
313 (43)
309 (9)
385 (100)
381 (18)
380 (24)
355 (35)
353 (15)
339 (49)
325 (13)
313 (19)
309 (24)
305 (4)
333 (47)
329 (19)
328 (16)
303 (7)
–
227 (100)
223 (24)
222 (10)
197 (48)
–
329 (73)
325 (15)
324 (17)
299 (17)
297 (3)
[M – MeO – C2H4]+
[M – Vin – CH2O – CH4]+
[M – Vin – 2CH2O]+
[M – MeO – 2C2H2 – CH4]+
[M – Vin – 2CH2O – CH4]+
[M – MeO – 2CH2O – CH4]+
[M – Vin – Vin(MeO)SiO]+
[M – MeO – Vin(MeO)SiO]+
[M – MeO – (MeO)2SiO]+
287 (67)
273 (6)
–
181 (23)
167 (53)
–
283 (33)
269 (7)
257 (65)
253 (100)
249 (11)
227 (49)
223 (59)
219 (9)
317 (49)
313 (13)
–
257 (100)
253 (15)
–
151 (27)
–
287 (13)
283 (15)
279 (5)
283 (13)
279 (11)
275 (2)
–
287 (21)
283 (9)
227 (59)
223 (10)
121 (18)
–
VinSiCl3 + Si(OMe)4 + Me2SO
Vin(MeO)2Si[OSiVin(OMe)]nOSiVin(OMe)2
2_4
+ (MeO)3Si[OSiVin(OMe)]OSi(OMe)3 + MeO[Vin(MeO)SiO]nSi(OMe)3
6, 7
5
OMe
OMe
MeO
O
O
m
+
+ ClCH2SMe
Si
Si
(2)
Vin
_
4 m
8_10
n = 0 (2), 1 (3, 6), 2 (4, 7); m = 1 (8), 2 (9), 3 (10).
functional groups occurs [Eq. (3)]. Note that etherifica-
tion of alkyl(aryl)trichlorosilanes with tetraalkoxy-
silanes was known [19], but under these conditions
(room temperature) it takes 48–190 h.
Me2SO
(3)
Vin(MeO)SiCl2 + ClSi(OMe)3
11
12
VinSiCl3 + Si(OMe)4
The formed vinyl(methoxy)dichlorosilane 11 is
apparently further converted to vinyl(methoxy)silanone
[Eq. (4)], and trimethoxy(chloro)silane 12, to the cor-
responding disiloxane 13 [Eq. (5)].
explained by insertion of vinyl(methoxy)silanone in
the starting Si(OMe)4 [Eq. (7)].
From the GC-MS data, the reaction of functional
group exchange does not terminate on stage (3) but
after addition of DMSO goes further with the forma-
tion of vinyl(chloro)dimethoxysilane 14 and dimethoxy-
dichlorosilane 15 [Eq. (8)]. Silane 14 is converted to
disiloxane 2, which also acts as a trap for sinanone
[Vin(MeO)Si=O] (compounds 3, 4). Methoxy(chloro)-
Hexamethoxydisiloxane 13 participates in the
parallel process of insertion of the Vin(MeO)Si=O
fragment with the formation of 3-vinyl-1,1,1,3,5,5,5-
heptamethoxydisiloxane 5 [Eq. (6)]. The presence
among the reaction products of compounds 6, 7 can be
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 87 No. 6 2017

NEW APPROACH TO THE SYNTHESIS OF LINEAR AND CYCLIC VINYL(ALKOXY)SILOXANES
1139
(4)
Vin(MeO)SiCl2 + Me2SO
[Vin(MeO)Si O] + ClCH2SMe
_HCl
(5)
2(MeO)3SiCl + Me2SO
(MeO)3SiOSi(OMe)3 + ClCH2SMe
_HCl
12
13
[Vin(MeO)Si O] + (MeO)3SiOSi(MeO)3
(MeO)3Si[OSiVin(OMe)]OSi(OMe)3
(6)
(7)
13
5
+
(MeO)[OSiVin(OMe)]nOSi(OMe)3
Si(OMe)4
n[Vin(MeO)Si O]
7, 8
n = 1, 2.
silane 15 is apparently further converted to the
cyclooligomerization with vinyl(methoxy)silanone
corresponding silanone, which enters the reaction of
affording compounds 8–10 [Eq. (9)] (Table 1).
Me2SO
Vin(MeO)2SiCl + Cl2Si(OMe)2
Vin(MeO)SiCl2 + ClSi(OMe)3
14
15
_ClCH2SMe
[Vin(MeO)Si=O]
[Vin(MeO)2Si]2O
(8)
(9)
3, 4
2
(MeO)2SiCl2 + Me2SO
[(MeO)2Si O] + ClCH2SMe
_HCl
MeO
Vin
OMe
OMe
O
O
n
n[Vin(MeO)Si
O] + 4-n[(MeO)2Si O]
Si
Si
_
4 n
8_10
n = 1_4.
The above reactions are observed also when using
tetraethoxysilane as a trap (Table 2). It is worth noting
that the reactions of functional group exchange in the
case of Si(OEt)4 proceed slower than with Si(OMe)4.
In this case, the linear and cyclic structures are formed
in the ratio of 73 : 27%.
The main routes of fragmentation of linear and
cyclic alkoxysilanes (Tables 1, 2) are in agreement
with the trends for the earlier studied methyl(alkoxy)
cyclosiloxanes, as well as for hexaethoxydisiloxane
[20]. The peaks of molecular and [M – 1]+ ions for all
studied compounds are lacking, which is typical for
siloxanes with alkoxy groups [20, 21]. As in the case of
methyl(alkoxy)cyclosiloxanes [20], the fragment [M –
HOR]+. is absent from the spectra of cyclotrisiloxanes,
but is observed in the spectra of linear alkoxysilanes
(Tables 1, 2). For linear and cyclic methoxysiloxanes
(Table 1), unlike ethoxy analogs, the fragmentation
with destruction of the siloxane backbone takes place.
Physicochemical constants and mass-spectra of Vin
(EtO)2SiOSiVin(OEt)2, triethoxychloro-silane, as well
The formation of cyclotrisiloxanes was detected
only in the reaction with Si(OEt)4. The main cyclic
products are cyclotetrasiloxanes. Probably, this is due
to the effect of the alkoxy substituent, since for di-
alkyldichlorosilanes the reactions with DMSO proceed
with the predominant formation of cyclotrisiloxanes
[11–13, 15–17]. The excess of tetraalkoxysilane results
in a decrease in the yield of cyclic compounds.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 87 No. 6 2017

1140
BASENKO, MAILYAN
Table 2. Principal characteristic ions in mass spectra of linear (20, 21) and cyclic (23–26) vinyl(ethoxy)siloxanes
m/z (Irel, %)
Ion
20
21
22
23
24
25
26а
[M – Vin]+
[M – EtO]+
[M – EtOH]+·
297 (36)
279 (100)
–
413 (5)
431 (4)
437 (5)
455 (7)
473 (9)
491 (5)
473 (40)
472 (20)
445 (3)
417 (12)
–
395 (17) 413 (10)
394 (4)
419 (12)
418 (2)
437 (19)
436 (5)
455 (29)
454 (10)
427 (5)
–
[M – EtO – C2H4]+
[M – EtO – 2C2H4]+
[M – Vin – 3C2H4]+
[M – EtO – 3C2H4]+
[M – Vin – 4C2H4]+
[M – EtO – 4C2H4]+
[M – Vin – 5C2H4]+
[M – EtO – 5C2H4]+
[M – Vin – 6C2H4]+
[M – EtO – 6C2H4]+
251 (17)
223 (14)
209 (12)
195 (16)
181 (11)
167 (27)
153 (6)
139 (30)
125 (8)
–
367 (11) 385 (5)
339 (100) 357 (100)
329 (32) 347 (5)
311 (38) 329 (49)
301 (23) 319 (6)
283 (38) 301 (21)
273 (21) 291 (7)
255 (32) 273 (13)
245 (21) 263 (15)
227 (30) 245 (16)
391(7)
409 (7)
363 (12)
353 (9)
381 (17)
371 (6)
399 (19)
389 (4)
335 (21)
325 (23)
307 (100)
297 (89)
279 (38)
269 (17)
251 (7)
353 (16)
343 (17)
325 (36)
315 (17)
297 (100)
287 (44)
269 (29)
371 (25)
361 (9)
389 (21)
–
343 (41)
333 (9)
361 (33)
–
315 (42)
305 (7)
333 (24)
–
287 (100)
305 (19)
a 287 (100).
as of compounds 2–4, 12, 15, coincide with the earlier
published data [22–27].
Commercial vinyltrichloro-, tetramethoxy-, and
tetraethoxysilanes were distilled prior to use. DMSO
was stored over melted KOH, decanted, frozen, and
distilled in a vacuum.
Therefore, an original approach to the synthesis of
the earlier unknown linear and cyclic vinyl(alkoxy)-
siloxanes as mixtures of oligomers based on com-
mercial vinyltrichlorosilane and tetraalkoxysilanes is
developed.
Reaction of vinyltrichlorosilane with DMSO.
DMSO (7.8 g, 0.1 mol) was added to the solution of
vinyltrichlorosilane (12.8 g, 0.1 mol) in 14.7 mL (15.2 g,
0.1 mol) of tetramethoxysilane at 0°С in argon during
1 h. The mixture was stirred for 4 h and distilled to
obtain 8.7 g (88%) of methyl(chloromethyl)sulfide, bp
110–111°С (bp 110–112°С [22]). Conversion to vinyl-
trichlorosilane 95%. Distillation of the residue in a
vacuum gave 13.6 g of fraction with bp 56–89°С
(2 Torr). The data of GC-MS study are presented in
Table 1.
EXPERIMENTAL
1H, 13С and 29Si NMR spectra were registered on a
Bruker DPX 400 instrument (400, 100 and 161.98 MHz)
in CDCl3, internal reference SiMe4. Electron ionization
mass spectra (70 eV) were recorded on a Shimadzu
GCMS-QP5050A spectrometer, temperature of
injector 200–250°С, of detector 200°С, gas-carrier
helium, quadruple mass-analyzer. Chromatographic
separation was performed on a capillary column SPB-5
(60 m × 0.25 mm × 0.25 μm), gas-carrier helium, flow
rate 0.7 mL/min; temperature of injector 230°С, of
ionic source 200°С, pressure 280 kPa, temperature
programming from 60 to 250°С at a rate 10 deg/min.
GC analysis was performed on a LKhM-8M chromato-
graph, column 1000×0.5 mm, 5% of SE-30 on Chro-
maton-N-AW, gas carrier – helium. Temperature of
injector 260°С, of catarometer 240°С. Temperature of
column was linearly programmed from 30 to 250°С at
a rate 20 deg/min.
Similarly the reaction of VinSiCl3 with DMSO
(molar ratio 1 : 1) in tetraethoxysilane was performed.
The data of GC-MS study of the reaction products are
summarized in Table 2.
1-Chloro-1-vinyl-1,3,3,3-tetramethoxydisiloxane
1
Vin(MeO)ClSiOSi(OMe)3 (1). H NMR spectrum, δ,
ppm: 6.02–6.54; 3.34; 3.53. 13С NMR spectrum, δ,
ppm: 144.80; 137.47; 54.44; 51.25. 29Si NMR spec-
trum, δ: –47.70; –85.49 ppm. Mass spectrum, m/z (Irel,
%): 231 (100) [M – Vin]+ , 230 (51) [M – C2H4]+, 201
(54) [M – Vin – CH2O]+, 187 (9), 185 (9), 171(13), 157
(15), 141 (22), 125 (20), 121 (16), 105 (18), 91 (14).
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 87 No. 6 2017

NEW APPROACH TO THE SYNTHESIS OF LINEAR AND CYCLIC VINYL(ALKOXY)SILOXANES
1141
Vinyl(methoxy)dichlorosilane,
Vin(MeO)SiCl2
REFERENCES
(11). 29Si NMR spectrum, δ: –23.4 ppm. Mass-spec-
trum, m/z (Irel, %): 155 (11) [M – H]+, 129 (76) [M –
Vin]+ , 128 (35) [M – C2H2]+, 115 (100) [M – Vin –
CH2]+, 99 (54) [M – Vin – CH2O]+, 79 (9), 63 (78).
1. Brinker, C.J. and Scherer, G.W., Sol-Gel Science: The
Physics and Chemistry of Sol-gel Processing, London:
Academic Press, 1990.
2. Mittal, K.L., Silanes and Other Coupling Agents,
Trimethoxy(chloro)silane, (MeO)3SiCl (12). 29Si
NMR spectrum, δ: –66.5 ppm. Mass-spectrum, m/z
(Irel, %): 156 (33) [M]+,, 155 (16) [M – H]+, 141 (18)
[M – Me]+ , 125 (66) [M – MeO]+, 120 (100), 111 (19),
95 (60) [M – MeO – CH2O]+.
Leiden: Brill, 2009, vol. 4, p. 348.
3. Greene, T.W. and Wuts, P.G.M. Greene’s Protective
Groups in Organic Synthesis, New Jersey: Wiley-Inter-
science, 2006, p. 1400.
4. Denmark, S.E. and Sweis, R.F., Chem. Pharm. Bull.,
2002, vol. 50, no. 12, p. 1531. doi 10.1248/cpb.50.1531
Vinyldi(methoxy)chlorosilane, Vin(MeO)2SiCl (14).
29Si NMR spectrum, δ: –41.3 ppm. Mass-spectrum,
m/z (Irel, %): 151 (11) [M – H]+, 137 (26) [M – Me]+ ,
125 (83) [M – Vin]+ , 111 (90) [M – Vin – CH2]+, 95
(100) [M – Vin – CH2O]+, 59 (60).
5. Shi, S. and Zhang, Y., J. Org. Chem., 2007, vol. 72,
no. 15, p. 5927. doi 10.1021/jo070855v
6. Voronkov, M.G. and Basenko, S.V., Silanony. Ot
efemerov k monomeram, oligomeram i polimeram
(Silanones. From Ephemerals to Monomers, Oligomers,
and Polymers), Novosibirsk: Geo, 2014.
Vinyl(ethoxy)dichlorosilane, Vin(EtO)SiCl2 (16).
29Si NMR spectrum, δ: –25.5 ppm. Mass-spectrum, m/z
(Irel, %): 169 (7) [M – H]+, 155 (100) [M – Me]+, 142
(17) [M – Vin]+ , 127 (73), 125 (85) [M – OEt]+, 119
7. Davidson, I.M.T. and Fenton, A., Organometallics,
1985, vol. 4, no. 11, p. 2060. doi 10.1021/om00130a025
8. Wiberg, N., J. Organomet. Chem., 1984, vol. 273, no. 2,
p. 141. doi 10.1016/0022-328X(84)80521-5
+
(87) [M – Cl – CH4]+, 115 (59), 99 (27) HSiCl2 .
9. Hussmann, G., Wulff, W.D., and Barton, T.J., J. Am.
Chem. Soc., 1983, vol. 105, no. 5, p. 1263. doi 10.1021/
ja00343a031
10. Barton, T.J. and Wulff, W.D., J. Am. Chem. Soc., 1979,
vol. 101, no. 10, p. 2735. doi 10.1021/ja00504a043
11. Basenko, S.V. and Voronkov, M.G., Dokl. Akad. Nauk,
Vinyldi(ethoxy)chlorosilane, Vin(EtO)2SiCl (17).
29Si NMR spectrum, δ: –43.5 ppm. Mass-spectrum,
m/z (Irel, %): 179 (5) [M – H]+, 165 (100) [M – Me]+,
153 (11) [M – Vin]+, 135 (67) [M – OEt]+, 125 (61),
121 (59), 107 (67) [VinSiCl(OH)]+.
1994, vol. 339, no. 4, p. 486.
12. Voronkov, M.G. and Basenko, S.V., J. Organomet.
Chem., 1995, vol. 500, p. 325. doi 10.1016/0022-328X
(95)00523-S
13. Basenko, S.V., Gebel, I.A., Voronkov, M.G., and
Mirskov, R.G., Russ. Chem. Bull., 1998, vol. 47, no. 8,
p. 1571. doi 10.1007/BF02495612
Triethoxy(chloro)silane, (EtO)3SiCl. 29Si NMR
spectrum, δ: –70.3 ppm. Mass-spectrum, m/z (Irel, %):
197 (9) [M – H]+, 183 (100) [M – Me]+, 169 (55) [M –
Et]+ , 155 (89), 153 (33) [M – OEt]+, 141 (43), 139 (39)
(EtO)SiCl(OMe)+, 125 (43) (EtO)SiCl(OH)+.
14. Basenko, S.V., Soldatenko, A.S., and Voronkov, M.G.,
Doklady Chem., 2013, vol. 451, p. 203. doi 10.1134/
S001250081308003X
15. Basenko, S.V., Gebel, I.A., Voronkov, M.G., Klyba, L.V.,
and Mirskov, R.G., Russ. J. Gen. Chem., 1998, vol. 68,
no. 2, p. 314.
16. Basenko, S.V., Voronkov, M.G., and Gebel, I.A., Russ.
Chem. Bull., 2000, vol. 49, no. 2, p. 363. doi 10.1007/
BF02494689
17. Basenko, S.V., Gebel, I.A., Boyarkina, E.V., and
Voronkov, M.G., Russ. J. Gen. Chem., 2004, vol. 74,
p. 882. doi 10.1023/B:RUGC.0000042423.40451.86
Diethoxydi(chloro)silane, (EtO)2SiCl2 (18). Mass-
spectrum, m/z (Irel, %): 187 (9) [M – H]+, 173 (100)
[M – Me]+, 159 (41) [M – Et]+ , 143 (33) [M – OEt]+,
137 (33) [M – Cl – CH4]+, 129 (35), 115 (67) HOSiCl2+.
1-Vinyl-1,3,3,5,5-pentaethoxycyclotrisiloxane,
[Vin(EtO)SiO][(EtO)2SiO]2 (19). Mass-spectrum, m/z
(Irel, %): 357 (100) [M – Vin]+, 339 (25) [M – OEt]+,
329 (49) [M – Vin – C2H4]+, 313 (55) [M – Vin –
C2H4O]+, 301 (21), 285 (31), 257 (13), 235 (28) [M –
Me – (EtO)2SiO]+, 217 (39), 199 (31), 183 (33), 167 (13).
18. Basenko, S.V. and Maylyan, A.A., Russ. Chem. Bull.,
2016, vol. 65, no. 4, p. 1034. doi 10.1007/s11172-016-
1409-9.
19. Chernyshev, E.A., Komalenkova, N.G., Tagachenkov, A.A.,
and Bykovchenko, V.G., Zh. Obshch. Khim., 1995,
vol. 65, no. 2, p. 281.
ACKNOWLEDGMENTS
The main results were obtained by the use of
equipment of the Baikal Center for Joint Usage of
Siberian Brunch of the Russian Academy of Sciences.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 87 No. 6 2017

1142
BASENKO, MAILYAN
20. Polivanov, A.N., Bernadskii, A.A., Silkina, N.N.,
Klimentov, B.N., and Bochkarev, V.N., Zh. Obshch.
Khim., 1980, vol. 50, no. 8, p. 1780.
24. Nagel, R., Tamborski, C., and Post, H.W., J. Org.
Chem., 1951, vol. 16, no. 11, p. 1768. doi 10.1021/
jo50005a017
21. Voronkov, M.G., Klyba, L.V., Basenko, S.V., Mir-
skov, R.G., and Bochkarev, V.N., Russ. Chem. Bull.,
1999, vol. 48, no. 1, p. 114.
25. Goubeau, J., Z. Anorg. Allg. Chem., 1953, vol. 272,
nos. 1–4, p. 2.
26. Roberts, J.M., Eldred, D.V., and Katsoulis, D.E., Ind.
Eng. Chem. Res., 2016, vol. 55, no. 6, p. 1813.
doi 10.1021/acs.iecr.5b04720
22. Bohme, H., Fisher, H., and Frank, R., Lieb. Ann., 1949,
vol. 563, no. 1, p. 54.
23. Voronkov, M.G., Basenko, S.V., Gebel’, I.A., and Mir-
skov, R.G., Izv. Akad. Nauk, Ser. Khim., 1988, no. 6,
p. 1406.
27. Varaprath, S. and Stutts, D.H., J. Organomet. Chem.,
2007, vol. 692, no. 10, p. 1892. doi 10.1016/
j.jorganchem.2006.12.032
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 87 No. 6 2017