Divergent reactivity of divinylsilanes toward sulfonamides in different oxidative systems

Article abstract of DOI:10.1039/d0ra07469a

Oxidative sulfonamidation of divinylsilanes with various sulfonamides in different solvents is reported. With t-BuOI as an oxidant, halogenation is the main process, whereas aziridines are the minor products. With NBS in CH2Cl2 the products of bromination or bromosulfonamidation were obtained, whereas in MeCN or THF the Ritter-type solvent interception products are formed. The obtained bromosulfonamidation products undergo base-induced cyclization to various heterocycles, including imidazolines, 1,4-oxazocanes, or Si,N-containing heterocycles of a new type, 1,3,5-diazasilinanes, in up to quantitative yield.

Full text of DOI:10.1039/d0ra07469a

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Divergent reactivity of divinylsilanes toward
sulfonamides in different oxidative systems†
Cite this: RSC Adv., 2020, 10, 40514
*
Mikhail Yu. Moskalik,
Vera V. Astakhova
and Bagrat A. Shainyan
Oxidative sulfonamidation of divinylsilanes with various sulfonamides in different solvents is reported. With
t-BuOI as an oxidant, halogenation is the main process, whereas aziridines are the minor products. With
NBS in CH2Cl2 the products of bromination or bromosulfonamidation were obtained, whereas in MeCN
or THF the Ritter-type solvent interception products are formed. The obtained bromosulfonamidation
products undergo base-induced cyclization to various heterocycles, including imidazolines, 1,4-
oxazocanes, or Si,N-containing heterocycles of a new type, 1,3,5-diazasilinanes, in up to quantitative yield.
Received 31st August 2020
Accepted 3rd November 2020
DOI: 10.1039/d0ra07469a
rsc.li/rsc-advances
BuOCl + NaI), while no reaction occurred in the presence of N-
bromosuccinimide (NBS).9 Also noteworthy are the reactions of
Introduction
trimethyl(vinyl)silane and dimethyl(divinyl)silane in the
absence of external oxidant but with pre-oxidized triamide in
the form of N,N-dichlorotriamide leading to the products of a-
chloro-b-triamidation in moderate yield.10 Of particular rele-
vance to the present work are two recent studies on the reac-
tions of trimethyl(vinyl)silane 1 and dimethyl(divinyl)silane 2
with sulfonamides in different oxidative systems.11 Thus, the
reaction in the system (t-BuOCl + NaI)11a has been proven to be
an effective approach to various heterocycles as shown in
Scheme 1.
Note, that the reactivity of triamide is principally different
from that of arenesulfonamides. With silane 1, it gives mainly
the product of bis(triamidation), whereas with arenesulfona-
mides N-sulfonylaziridines were obtained in high yield. With
silane 2, most remarkable is the formation of 3-(triyl)-5-
(triamido)oxazolidine in the reaction with triamide.
The course of the NBS-induced reaction of silane 1 with
sulfonamides is strongly solvent dependent.11b In CH2Cl2, the
products of a-bromo-b-sulfonamidation were formed regiose-
lectively in good yield. The latter underwent base-induced
dehydrobromination to give the corresponding aziridines in
a very high yield. In acetonitrile or THF, silane 1 with triamide
affords the solvent interception products, which were converted
to 1-triyl-2-methyl-5-(trimethylsilyl)-2-imidazoline or 4-triyl-3-
(trimethylsilyl)-1,4-oxazocane in almost quantitative yield
(Scheme 2).11b
Unsaturated organosilicon compounds are valuable building
blocks, which play an important role in the synthesis of large
molecules due to the diverse transformations they can
undergo.1 Thus, alkenyl- and dienyl silanes2 are excellent
reagents in various W, Mo, Re and Ru-catalyzed metathesis
reactions.3 Functionalized allyl- and vinylsilanes obtained by
the addition of silyl cuprates to alkenes, dienes or acetylenes are
used in the synthesis of natural products (salicylihalamide,
tetrahydrolipstatin and ebelactone A), and stereoselective
synthesis of di- and trisubstituted alkenes.4 Vinyl- and alky-
nylsilanes are important reagents for the synthesis of carbo-
cycles, as well as N- and O-containing heterocycles, including
alkaloids.5 Pd- and Ru-catalyzed cross-coupling of alkenes with
vinylsilanes and -siloxanes can proceed with desilylation or with
retention of the silyl group to afford p-conjugated systems
(stilbenes, styryl halogenides, chalcones).6 In the presence of Cu
and Cs salts, similar reactions occur with desilylation and
formation of dienes.7 Bis-alkynes are hydrosilylated with bis-
vinylsilanes in the presence of Rh-catalysts to give conjugated
organosilicon chromophores possessing unique optoelectronic
properties.8 A specic type of transformations of unsaturated
silanes of great potential interest is their oxidative sulfonami-
dation, since it allows to introduce not only pharmacophore
sulfonamide fragment in the molecule, but also a halogen as
a good leaving group, opening the way to further modications.
However, the information on this issue is very scarce. Very
recently, oxidative triamidation of several allylsilanes in
different oxidative systems was shown to proceed with desily-
lation and formation of silicon-free products in the system (t-
As seen from the above literature analysis, two important
issues have not been addressed. First, the reactions of NBS-
induced oxidative sulfonamidation of silanes 2 and 3 were not
studied, although the nature of the oxidant can play a pivotal
role in determining the course of the reaction (vide supra).
Second, the reaction path may change by replacing the methyl
by a phenyl substituent at silicon. Unlike in classical organic
chemistry, the phenyl group at silicon can be considered as
A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Division of Russian Academy of
Sciences, 664033 Irkutsk, Russia. E-mail: bagrat@irioch.irk.ru
† Electronic supplementary information (ESI) available. See DOI:
10.1039/d0ra07469a
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Scheme 1 Products of sulfonamidation of silanes 1 and 2 in the system (t-BuOCl + NaI)/MeCN.
a functional group because of the possibility of the Si–C bond of this multifactor study as well as of the base-induced reactions
cleavage. More feasible splitting of the Si–Ph as compared to the of the products of bromosulfonamidation are presented below.
Si–Me bond is consistent with a longer Si–Ph with respect to Si–
Me bond in spite of larger Csp vs. Csp covalent radius.12
3
2
Results and discussion
Therefore, the second aim of this study was to investigate the
effect of substitution of methyl by phenyl groups in silane 2, Firstly, we performed the reaction of silane 3 with nosylamide,
and, indeed, as will be shown below, such a replacement in which was chosen as the most close to triamide in the NH
some cases substantially changed the course of the reaction.
acidity. However, the reaction with nosylamide proceeded in
With these two goals in mind, and in order to investigate the a different way (Scheme 3). No desilylation, like in Scheme 1,
dependence of the reaction on the nature of the reagents, the occurred; instead, the products of mono (4, major) and bis-a-
oxidant, and the solvent, we have studied the reactions of iodo-b-chlorination (5, minor), mono (6) and bis-aziridination
silanes 2 and 3 with triamide (TfNH2), methanesulfonamide (7), as well as trace amounts of 3,5-diiodo-1-(4-
(MsNH2) and arenesulfonamides p-RC6H4SO2NH2 (R ¼ Me, nitrophenylsulfonyl)-4,4-diphenyl-1,4-azasilinane
8
were
MeO, NO2) in the presence of different oxidants [(t-BuOCl + NaI) formed (Scheme 3). Although heterocycles 6–8 are similar to
or NBS] in different solvents (MeCN, THF, CH2Cl2). The results those of the reaction of nosylamide with silane 2,11b their
content is drastically different, being, in total, 68% in the
Scheme 2 NBS-induced sulfonamidation of trimethyl(vinyl)silane.
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Scheme 3 Reaction of diphenyl(divinyl)silane 3 with nosylamide in the system (t-BuOCl + NaI).
Scheme 4 Possible mechanism of independent halogenation versus aziridination via the same iodonium ion intermediate.
reaction with silane 2 and only 26% in the reaction with its Si– may be indicative of independent formation of the products of
Ph analogue, silane 3. halogenation 4, 5 and aziridines 6, 7, as shown in Scheme 4 on
Because of low content of product 8, we were unable to the example of the adducts at one double bond.
isolate it from the reaction mixture; however, its formation was A low content of the products of sulfonamidation 6–8 (<30%)
proved by the presence of signals, similar to those of azasili- as compared to undesired products of halogenation 4, 5 (65%)
1
nanes shown in Scheme 1 and described earlier,11b in the H when using the oxidative system (t-BuOCl + NaI) prompted us to
NMR spectrum of the fraction enriched with diaziridine 7 and replace it with NBS. The use of NBS as an oxidant in similar
containing ca. 11% of azasilinane 8.
reactions was shown to be effective due to the lower resin-
Next, we tried the reaction of compound 4 with nosylamide ication of the reaction mixture and the amount of side prod-
in order to replace one or both halogen atoms by the amide ucts.11 The reaction of silanes 2 and 3 with a series of
residue and obtain, aer cyclization, aziridine 6. However, apart sulfonamides in the presence of NBS was performed in CH2Cl2
from the unreacted nosylamide, the only product isolated in and MeCN as solvents and with various ratios of the reagents.
76% yield was the product of dihalogenation 5 (Scheme 4). This The results are summarized in Scheme 5 and Table 1.
Scheme 5 NBS-induced reaction of (divinyl)silanes 2, 3 with sulfonamides.
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Table 1 Products of the reaction of silanes 2 and 3 with sulfonamides (Scheme 5)
Yielda, %
Conversion,
%
Entry
R
R0
Solvent
R0SO2NH2/NBS
9
10
11
12
13
1
2
3
4
5
6
7
8
9
Me
CF3
48
80
37
0
42
38
53
72
81
79
CH2Cl2
MeCN
MeCN
MeCN
MeCN
MeCN
CH2Cl2
MeCN
MeCN
MeCN
1 : 1
1 : 1
1 : 5
1 : 1
1 : 1
1 : 1
1 : 1
1 : 1
1 : 5
1 : 5
53
6
—
81
8
30
30
9
—
—
2b
—
—
—
—
—
12
14
39
—
—
—
37
15
46
—
—
—
—
88
—
—
—
—
—
68
—
—
—
—
46
—
—
—
—
—
60
65
Me
Tol
p-NO2C6H4
CF3
Ph
—
—
10
p-NO2C6H4
a
b
Isolated yields taking into account the conversion. From 1H NMR.
Although the yields in Table 1 seem to vary irregularly, the change of the reaction course in going to p-methox-
following conclusions can be made: (i) in the reactions of yphenylsulfonamide. In contrast to the reactions with other
silanes 2 and 3 with TfNH2 in CH2Cl2 the products of mono- sulfonamides in Scheme 5, the reaction of silane 3 with p-
bromination 9 and bromotriamidation 11 are formed in methoxyphenylsulfonamide in acetonitrile in the presence of
comparable amounts (entries 1, 7); (ii) dibromination is a minor ve-fold excess of NBS afforded monoadduct 9 (28%), diadduct
process with both silanes 2 and 3 and occurs only with large 10 (11%) and, unexpectedly, as the major product, 40% of N-{2-
excess of NBS (1 : 5) and only with most acidic sulfonamides bromo-2-[diphenyl(vinyl)silyl]ethyl}acetamide 14 rather than
TfNH2 and NsNH2, most probably, due to higher electrophilicity amidine of the type 12 or 13 having the –CH(Br)CH2NHC(Me) ¼
of the bromine atom in most acidic intermediate N-bromo- NSO2R0 motif. Apparently, the reaction proceeds via the inter-
sulfonamides TfNHBr and NsNHBr. The major product in this mediate bromonium cation opened by acetonitrile and subse-
case is the Ritter-type product of bromosulfonamidation of one quently quenched with traces of water in the solvent (Scheme 6).
double bond 12 and bromination of the other double bond 13 Such a specic reactivity can be explained by the presence of
(entries 3, 9, 10). With the equimolar ratio (R0SO2NH2/NBS ¼ a strong basic center in the molecule of the reagent – the
1 : 1), the major product is the Ritter-type product of bromo- methoxy group, which increases the nucleophilicity of water by
sulfonamidation of one and retention of the other double bond hydrogen bonding to the ethereal oxygen atom.
12, and the minor one is the product of bromination of one
THF, when used as the solvent, is a cyclic ether with the
double bond 9 (entries 2, 8); (iii) silane 2 gives the Ritter-type oxygen atom more basic than that of the methoxy group in p-
products 12 and 13 only with TfNH2, and not with MsNH2 or methoxyphenylsulfonamide, and it directly participates in the
aromatic sulfonamides (entries 4–6), whereas silane 3 gives reaction of oxidative sulfonamidation in the presence of NBS.
products 13 with both most acidic sulfonamides, TfNH2 and Two Ritter-type products of solvent interception with the THF
NsNH2 (entries 9, 10). Formation of the Ritter-type product 13 in ring opening, with retention of the second double bond, were
the reaction of silane 3 with NsNH2 and its absence in the isolated from the reaction of silanes 2 and 3 with all types of
reaction of silane 2 is another demonstration of substantial sulfonamides (TfNH2, MsNH2, ArSO2NH2) – [1-bromo-2-(4-
inuence of the phenyl substituent.
bromobutoxy)ethyl](diorganyl)vinylsilanes 15 and N-(4-{2-
A vivid illustration of strong dependence of the reaction of bromo-2-[diorganyl(vinyl)silyl]ethoxy}butyl)sulfonamides
oxidative sulfonamidation on the nature of the reagent is the (Scheme 7, Table 2).
16
Scheme 6 Possible mechanism of formation of b-silylated acetamide 14.
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Scheme 7 NBS-induced reaction of (divinyl)silanes 2, 3 with sulfonamides in THF.
Table 2 Products of the reaction of silanes 2 and 3 with sulfonamides
lower and, remarkably, the ratio of products 16 : 15 changes in
favor of the latter. Therefore, both the absolute yield of the
Ritter-type product of sulfonamidation 16, and its predomi-
nance (ratio 16 : 15) decrease with lowering the NH acidity of
the reagent (on the example of silane 2): 11 (TfNH2) > 9 (NsNH2)
> 1.1 (TsNH2) > 0.3 (MsNH2).
The products of bromosulfonamidation 11–13, 16 contain-
ing in one molecule simultaneously the bromine atom and the
sulfonamide moiety with free NH group are potential precur-
sors for the synthesis of various heterocycles via HBr elimina-
tion. Indeed, the products of bromoarenesulfonamidation 11
were successfully converted into the corresponding aziridines
17 by the reaction with excess potassium carbonate in almost
quantitative yield (Scheme 8). In contrast, the similar product of
bromotriamidation of silane 3 did not enter the reaction. This
result clearly demonstrates different reactivity of silanes 2 and
3, and is in full agreement with the one reported earlier for the
substrates similar to 11, except the silyl substituent was Me3Si,
where no reaction occurred for R0 ¼ CF3 while for R0 ¼ Ar the
yields were practically quantitative.11a
in THF (Scheme 7), R0SO2NH2/NBS ¼ 1 : 1
Yielda, %
Conversion,
%
Entry
R
R0
15
16
1
2
3
4
5
6
Me
CF3
Me
Tol
p-NO2C6H4
CF3
80
27
55
59
92
87
8
89
17
35
80
74
72
52
31
9
21
18
Ph
p-NO2C6H4
a
Isolated yields taking into account the conversion.
Table 3 Yields of the products of reaction of arensulfonamides with
12a or 18 in MeCN (Scheme 10)
Yield of 19,
%
Substrate
Ar in ArSO2NH2
12a
18
p-ClC6H4
p-Tol
99
97
98
The Ritter-type products 12, 13 and 16 were also examined in
the reaction of base-induced heterocyclization. Amidines 12 gave
5-[diorganyl(vinyl)silyl]-2-methyl-1-triuoromethylsulfonyl-2-
imidazolines 18 (Scheme 9).
p-NO2C6H4
The reaction in Scheme 9 proceeds under mild conditions
and in almost quantitative yield, suggesting that, unlike in
adducts 11, a more remote triyl group in amidines 12 does not
prevent the formation of the product of heterocyclization.
In a hope to involve the second double bond of amidines 12 or
imidazolines 18 in the reaction of bromosulfonamidation/
heterocyclization, we tried the one-pot reaction by successive
addition of amidine 12a or imidazoline 18 (R ¼ Ph) to the solu-
tion of arenesulfonamides and NBS in acetonitrile and two-fold
The analysis of Table 2 shows that the highest overall yield of
$95% with high conversion is obtained in the reactions with
triamide (entries 1, 5). Also, good yields (ꢀ90%) are observed
for nosylamide, although the conversion is somewhat lower
(entries 4, 6). In all these reactions, the products of bromo-
sulfonamidation strongly predominate. With tosylamide, and
especially with mesylamide, the conversion and the yield are
Scheme 8 Intramolecular dehydrobromination of compounds 11.
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Scheme 9 Dehydrobromination of amidines 12 to imidazolines 18.
Scheme 10 Desilylation of compounds 12a and 18 (R ¼ Ph) in the system (NBS + K2CO3).
excess K2CO3. Surprisingly, instead of the expected bisimidazo- However, neither of these expectations was conrmed. Instead,
line, the only product isolated in almost quantitative yield was the previously unknown type of heterocycles, 1,3,5-dia-
2,2,4,4,6,6,8,8-octaphenyl-1,3,5,7,2,4,6,8-tetraoxatetrasilocane 19 zasilinanes 20 were isolated in close to quantitative yield under
(Scheme 10). Cyclic siloxane 19 is a known compound13 as very mild conditions by stirring amidines 13 with two-fold
a monomer for organosilicon polymers used as a precursor for excess of K2CO3 in acetonitrile at room temperature (Scheme
the synthesis of phase-transfer catalysts. The structure of 11, Table 4). The structure of compounds 20 was unequivocally
(Ph2SiO)4 19 was proved by NMR spectroscopy, in particular, by proved by the elemental analysis data and the presence of only
1
comparison of its H and 13C spectra (7.48, 7.35, 7.19 ppm and three signals in the alicyclic part of the 13C NMR spectra
134.4, 134.3, 130.0, 127.6 ppm) with those reported in the liter- belonging to one CH3 and two CH2 groups (as proved by Jmod
ature (7.48, 7.36, 7.19 and 134.4, 130.1, 127.7 ppm).13a Presum- and proton-coupled 13C NMR spectra), as well as by the intensity
1
ably, fragmentation of the molecule is due to steric ratio of the signals in the H NMR spectra (see ESI†).
overcongestion of the expected product, which would have four
To the best of our knowledge, the only so far known six-
bulky substituents at silicon (two phenyl groups and two membered heterocycles with one silicon and two nitrogen
secondary substituents of isopropyl type). The oxygen atoms, atoms were 1,4,2-diazasilinanes prepared by insertion of N-
apparently, come from water eliminated from the reaction of the heterocyclic carbenes into the Si–H bond.14 The discovery of
formed HBr with K2CO3.
a new type of heterocycles is one of the most signicant results
One of the most interesting was the reaction of the Ritter- of the present study. Although the detailed mechanism of the
type products 13a, 13b, 13d, having the 1,2-dibromoethyl reaction in Scheme 11 deserves special consideration, a tenta-
substituent instead of the former vinyl group at silicon, with tive mechanism including two successive eight- to six-
K2CO3. The compounds expected to be formed during dehy- membered ring contraction steps can be proposed (Scheme
drobromination were heterocycles similar to azasilinanes 12). The reaction starts with b-bromine substitution in 13 and
(Scheme 3), aziridines (Scheme 8), or imidazolines (Scheme 9). formation of intermediate (A). An alternative mechanism with
Scheme 11 Based-induced dehydrobromination/heterocyclization of amidines 13a, 13d.
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Table 4 Yields of the products of reaction of 13a, 13d with K2CO3
(Scheme 11)
In a search for experimental evidences in support of the
mechanism in Scheme 12, we performed H NMR and GC-MS
1
monitoring of the reaction mixture (13d + K2CO3, R1 ¼ Ph).
Although no direct detection of specic structures was
observed, the changes in the NMR spectrum (Fig. S73†) indicate
the formation of reaction intermediates clearly distinct from the
reagent. This is evidenced by disappearance of the multiplets at
3.0, 3.3, 4.3 and 4.4 ppm belonging to amidine 13d, and the
appearance of unresolved signals in the range 3.4–4.2 ppm,
which rst increase and then decrease in intensity, up to complete
disappearance (Fig. S73†). Apparently, they belong to numerous
methine and diastereotopic methylene protons in intermedi-
ates A and B, having chiral carbon atoms.
Transformations of intermediates A and B include the
rupture of the Si–CHBr bonds. The possibility of such a process,
at least by electron impact in mass spectrometry, is indicated by
the presence of a doublet peak at m/z 261 and 263, belonging to
[Ph2SiBr]+ ion in the mass spectrum.
Similar to Scheme 9, the replacement of the a-bromine atom
was found to occur through the base-induced 1,8-cyclization of
the THF interception products 16a–d into the corresponding
1,4-oxazocanes 21 (Scheme 13, Table 5).
Remarkably, the yield of cyclization is practically quantita-
tive for both derivatives of silane 3 (R2 ¼ Tf, Ns), whereas for the
derivative of silane 2 with R2 ¼ Tf it is also close to 100%, but no
reaction occurred with other sulfonamides (mesylamide,
Yield of 20,
%
Entry
R1
R2
1
2
3
Me
Ph
Tf
Tf
Ns
94
97
96
the nucleophile attacking the silicon atom in A, which might be
preferable due to high oxophilicity of silicon, is sterically
hindered by four bulky substituents, two Ph and two CHBr
groups at silicon. Intermediate A undergoes two similar
consecutive steps of nucleophilic attack on the CHBr group with
the Si–CHBr bond rupture/Si–CH2 bond formation/C–CHBr
bond rupture, resulting in successive ring contraction A / B /
20. This follows from the comparison of the reaction paths for
amidines 12 and 13 in Schemes 9 and 11 differing only in one
substituent at silicon: the vinyl group in 12 remains intact and
the ring closure occurs within the a-bromo-b-amidino struc-
tural motif, whereas in adducts 13 the 1,2-dibromoethyl group
is involved in heterocyclization. The leaving group [HOCHBr]ꢁ
may react with water with elimination of HBr and CH2O and
regeneration of HOꢁ anion.
Scheme 12 Tentative mechanism of formation of 1,3,5-diazasilinanes 20 by the based-induced dehydrobromination/heterocyclization of
amidines 13a, 13d.
Scheme 13 Dehydrobromination of 16a–d with potassium carbonate.
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Table 5 Yields of the products of the reaction of 16a–d with potas-
sium carbonate (Scheme 13)
the ring opening and interception of the THF molecule leads to
3-silylated 1,4-oxazocanes with the yield close to 100% for tri-
amide or nosylamide derivatives, but no reaction occurred
with the mesylamide or tosylamide analogues.
Entry
R1
R2
Yield of 21a–d, %
Therefore, the present work, on the one hand, considerably
increases the synthetic potential of unsaturated silanes in the
reactions of oxidative sulfonamidation, and, on the other hand,
when comparing with the previous studies, reveals the pivotal
role of the substituent at silicon in determining the course and
feasibility of the reactions leading to new heterocyclic and
polyfunctional otherwise hardly accessible organosilicon
compounds.
1
2
3
4
5
6
Ph
Me
Tf
99
98
0
0
0
Ns
Ms
Ts
Ns
Tf
98
tosylamide or nozylamide). Comparison of entries 2 and 5 in
Table 5 provides another evidence that the replacement of the
methyl by the phenyl groups at silicon may play a decisive role
in determining the feasibility of the reaction.
Experimental
General information
All starting materials have been previously described in litera-
1
ture. All products were identied by H, 13C, 19F and 29Si NMR
Conclusions
spectroscopy and comparison with authentic samples. IR
spectra were taken on a Bruker Vertex 70 spectrophotometer in
KBr. NMR spectra were recorded in CDCl3 and CD3CN on
Bruker DPX 400 spectrometer at working frequencies 400 (1H),
100 (13C), 376 (19F) and 79.5 (29Si) MHz. All shis are reported
in ppm relative to residual CHCl3 peak [7.27 (1H) and 77.2 (13C)
ppm] and CD3CN peak [1.95 (1H), 1.3 and 118 (13C) ppm]. All
coupling constants (J) are given in hertz (Hz). Abbreviations
are: s, singlet; d, doublet; t, triplet; q, quartet; br s, broad
singlet. Melting points were measured on a Boetius apparatus
(VEB Analytik). Flash chromatography was performed on silica
To summarize, divinylsilanes show diverse reactivity in oxida-
tive sulfonamidation reactions, depending on the substituents
at silicon, the oxidative system used and the solvent. In the
oxidative system (t-BuOCl + NaI) the main reaction is haloge-
nation of one or both double bonds; mono- and diaziridines are
the minor products. With NBS, as the oxidant, the course of
reaction is governed by nature of the substituent in sulfonamide
and the solvent: in CH2Cl2 the products of bromination or
bromosulfonamidation are formed, whereas in MeCN the
Ritter-type products with interception of the solvent are formed
with triamide and nosylamide. In THF as the solvent, two
Ritter-type products of solvent interception with opening of the
THF ring and retention of the second double bond of the
substrate were isolated, the major one being the products of
bromosulfonamidation – N-(4-{2-bromo-2-[diorganyl(vinyl)silyl]
ethoxy}butyl)sulfonamides. Such a dramatic change of the
reaction course by simple variationof the substituent at silicon
from the Me to the Ph group seems to be a striking phenom-
˚
gel, 60 A, 300 mesh. TLC analysis was carried out on aluminum
plates coated with silica gel 60 F254, 0.2 mm thickness, visual-
ized by 254 nm UV lamp or aqueous NaIO4 solutions. All NMR
spectra are given in the ESI.†
Synthesis and characterization of compounds
Reaction of p-nitrobenzenesulfonamide with diphenyl(di-
enon and deserves special consideration. Preliminarily, it can vinyl)silane 3 in the system t-BuOCl + NaI. To the solution of p-
be assumed that is due to a combined action of different nitrobenzenesulfonamide (1.40 g, 7 mmol) and NaI (3.12 g, 21
bulkiness and electronic effects of the two groups, as well as the mmol) in 70 ml CH3CN diphenyl(divinyl)silane 3 (1.64 g, 7
Si–C bond lengths.
mmol) was added, the mixture cooled to ꢁ30 ꢂC, t-BuOCl
The base-induced cyclization of the products of bromoar- (2.38 ml, 21 mmol) was added dropwise in the dark, the ob-
enesulfonamidation gives rise to the corresponding aziridines tained mixture kept for 1.5 h at ꢁ30 ꢂC, then 23 h at room
in close to quantitative yield, whereas no reaction occurs with temperature. Aer completion of the reaction, the solvent was
the similar product of bromotriamidation. The Ritter-type removed at a reduced pressure, the residue dissolved in 50 ml of
products of bromotriamidation formed in MeCN (amidines ethyl acetate and treated with 60 ml of aqueous Na2S2O3. The
with the intact vinyl group at silicon) afford 5-silylated 2-methyl- extract was dried over CaCl, solvent removed in vacuum, the
1-(triuoromethylsulfonyl)-2-imidazolines in almost quantita- light-yellow residue (3.61 g) was placed in a column with coarse
tive yield. In contrast, in the reaction of amidines with the vinyl silica and eluted successively with hexane, Et2O : hexane 1 : 1,
group at silicon brominated to 1,2-dibromoethyl group, 1,3,5- Et2O. From the hexane eluate, compounds 4 (1.33 g, 48%) and 5
diazasilinanes, were obtained also in close to quantitative yield. (0.68 g, 17%) as a mixture of diastereomers were isolated. From
The latter compounds are the rst representatives of the so far ether–hexane eluate, light-yellow powder was obtained, which
unknown type of Si,N-containing heterocycles. A trial to involve was puried on ne silica using hexane and hexane–ether 1 : 1
the second double bond in the formation of the corresponding as
eluents
to
give
2-(diphenyl(vinyl)silyl)-1-(4-
bisimidazolines led to desilylation and formation of cyclic nitrophenylsulfonyl)aziridine 6 (0.21 g, 20%) as white powder.
siloxane D4 [(Ph2SiO)4] in practically quantitative yield. The From the rst portion of Et2O eluate, 0.35 g of unreacted p-
base-induced heterocyclization of the Ritter-type products with nitrobenzenesulfonamide precipitated. From the nest portions,
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a yellow powder was obtained, which was further puried on diphenyl(divinyl)silane 3 and 5-fold excess of NBS in CH3CN
a column with coarse silica eluted with hexane and hexane– was performed as above and eluted successively with hexane
ether 1 : 1 to afford (0.09 g, 6%) of 1-(4-nitrophenylsulfonyl)-2- and hexane–ether 1 : 1. From the hexane eluate, bis(1,2-
((1-(4-nitrophenylsulfonyl)aziridin-2-yl)diphenylsilyl)aziridine 7 dibromoethyl)diphenylsilane 10 (0.43 g, 12%) was isolated as
as a white powder and 3,5-diiodo-1-(4-nitrophenylsulfonyl)-4,4- a light-yellow oil, from hexane–ether extract – unreacted tri-
diphenyl-1,4-azasilinane 8 (for 8 the yields are given based on amide (0.19 g) and yellow oil, which was eluted on ne silica
the 1H NMR spectroscopy data).
with hexane and hexane–ether–chloroform 1 : 4:1 to give N-(2-
Reaction of p-nitrobenzenesulfonamide with (2-chloro-1- bromo-2-((1,2-dibromoethyl)diphenylsilyl)ethyl)-N0-(tri-
iodoethyl)diphenyl(vinyl)silane 4 in the system t-BuOCl + NaI. uoromethylsulfonyl)acetamidine 13a (R ¼ Ph) (2.17 g, 60%) as
The reaction of the solution of p-nitrobenzenesulfonamide an oil crystallized upon long standing. The reaction with silane
(0.35 g, 1.7 mmol) and NaI (0.77 g, 5.1 mmol) with compound 4 2 was performed and treated similarly to afford 0.63 g of
(0.68 g, 1.7 mmol) was performed and treated as described unreacted triamide and N-(2-bromo-2-((1,2-dibromoethyl)
above. The obtained light-yellow residue (1.07 g) was analyzed dimethylsilyl)ethyl)-N0-(triuoromethylsulfonyl)acetamidine
by NMR spectroscopy, which showed the presence of product 5 13a (R ¼ Me) (0.62 g, 46%).
(76%) and unreacted 4 (8%).
Reaction of sulfonamides with dimethyl(divinyl)silane 2 in
Reaction of triamide with diphenyl(divinyl)silane 3 and the presence of NBS in CH3CN
NBS in CH2Cl2. To the solution of triamide (1.00 g, 6.7 mmol)
General procedure. To a solution of 6.4–11.0 mmol of
and NBS (1.20 g, 6.7 mmol) in 70 ml CH2Cl2 silane 3 (1.58 g, 6.7 sulfonamide (MsNH2, TsNH2, NsNH2) and 6.4–11.0 mmol of
mmol) was added, the mixture kept for 20 h. Then, CH2Cl2 was NBS in 70 ml CH3CN dimethyl(divinyl)silane 2 (6.4–11.0 mmol)
removed at a reduced pressure, the residue dissolved in 70 ml of was added, the mixture kept for 20 h. Solvent was removed at
ether, succinimide ltered off, ltrate evaporated, the residue a reduced pressure, the residue dissolved in 70 ml of ether,
(3.79 g) separated by column chromatography eluting succes- succinimide ltered off, ltrate evaporated, the residue (2.36–
sively with hexane and hexane–ether 1 : 1. From the hexane 3.93 g) separated by column chromatography eluting succes-
extract, (1,2-dibromoethyl)diphenyl(vinyl)silane 9 (0.80 g, 30%) sively with hexane and hexane–ether 1 : 1 (1 : 2). From the
was isolated as light-yellow oil, from hexane–ether extract – hexane eluate, compound 9 (R ¼ Me) was isolated, from
unreacted triamide (0.47 g) and yellow oil were obtained, hexane–ether extract
– the corresponding N-(2-bromo-2-
which was puried by column chromatography on ne silica (dimethyl(vinyl)silyl)ethyl)sulfonamide 11c, 11d (R ¼ Me) and
using hexane and hexane–ether 5 : 1 as eluents to give N-(2- unreacted sulfonamide.
bromo-2-(diphenyl(vinyl)silyl)ethyl)triamide 11a (0.76 g, 46%)
(R ¼ Ph) as a colorless oil crystallized upon long standing. The 81%.
reaction with dimethyl(divinyl)silane 2 and treatment of the
reaction mixture was carried out similarly. From hexane, (1,2- tosylamide (0.87 g) and N-(2-bromo-2-(dimethyl(vinyl)silyl)
dibromoethyl)dimethyl(vinyl)silane 9 (0.97 g, 53%) was isolated ethyl)-4-methylbenzenesulfonamide 11c (R ¼ Me). (0.49 g,
as colorless liquid, from hexane–ether extract – unreacted tri- 37%).
With MsNH2. Compound 9 (R ¼ Me) MsNH2. Yield 2.43 g,
With TsNH2. Compound 9 (R ¼ Me) (0.18 g, 8%), unreacted
amide (0.52 g) and yellow oil were obtained, which was puri-
With NsNH2. Compound 9 (R ¼ Me) (0.52 g, 30%), unreacted
ed on ne silica using hexane and hexane–ether 1 : 1 as nosylamide (0.81 g) and N-(2-bromo-2-(dimethyl(vinyl)silyl)
eluents, to give N-(2-bromo-2-(dimethyl(vinyl)silyl)ethyl) ethyl)-4-nitrobenzenesulfonamide 11d (R ¼ Me) (0.14 g, 15%).
triamide 11a (R ¼ Me) (0.42 g, 39%) as a colorless oil.
Reaction of p-nitrobenzenesulfonamide with diphenyl(di-
Reaction of triamide with diphenyl(divinyl)silane 3 and vinyl)silane 3 in the presence of NBS in CH3CN. To the solution
NBS in CH3CN. The reaction of the solution of triamide of p-nitrobenzenesulfonamide (1.00 g, 5.0 mmol) and NBS
(1.00 g, 6.7 mmol) and NBS (1.20 g, 6.7 mmol) with silane 3 (3.52 g, 25 mmol) in 70 ml CH3CN diphenyl(divinyl)silane 3
(1.58 g, 6.7 mmol) was performed and treated as described (1.17 g, 5.0 mmol) was added, the mixture kept for 20 h, solvent
above. From the hexane extract, compound 9 (R ¼ Ph) (0.23 g, removed at a reduced pressure, the residue dissolved in 70 ml of
9%) was isolated, from hexane–ether extract – unreacted tri- ether, N-succinimide ltered off, ltrate evaporated, the residue
amide (0.28 g) and yellow oil were obtained. The latter was (3.42 g) separated by column chromatography eluting succes-
puried by column chromatography on ne silica using hexane sively with hexane and hexane–ether 1 : 2. From the hexane
and hexane–ether 2 : 1 as eluents to give N-(2-bromo-2-(diphe- extract bis(1,2-dibromoethyl)diphenylsilane 10 (R ¼ Ph) (0.39 g,
nyl(vinyl)silyl)ethyl)-N0-(triuoromethylsulfonyl)acetamidine
14%) was isolated as a light-yellow oil, from hexane–ether
12a (R ¼ Ph) (1.65 g, 68%) as a light-yellow oil. The reaction with extract – unreacted nosylamide (0.21 g) and yellow oil, which
dimethyl(divinyl) silane 2 and treatment of the reaction mixture was puried by column chromatography on ne silica with
was carried out similarly. From hexane, compound 9 (R ¼ Me) hexane and hexane–ether-chloroform 1 : 3:2 as eluents. N-(2-
(0.11 g, 6%) was isolated, from hexane–ether extract – unreacted Bromo-2-((1,2-dibromoethyl)diphenylsilyl)ethyl)-N0-(4-nitro-
triamide (0.20 g) and N-(2-bromo-2-(dimethyl(vinyl)silyl)ethyl)- phenylsulfonyl)acetamidine 13d (1.81 g, 65%) was obtained as
N0-(triuoromethylsulfonyl)acetamidine 12a (R ¼ Me) (1.82 g, a light-yellow oil crystallized upon long standing.
88%) as a light-yellow oil.
The
reaction
of
the
solution
of
4-methox-
The reaction of triamide with diphenyl(divinyl)silane 3 and ybenzenesulfonamide (0.80 g, 4.3 mmol) with silane 3 (1.01 g,
5-fold excess of NBS in CH3CN. The reaction of triamide with 4.3 mmol) and NBS (4.00 g, 21 mmol) in 70 ml CH3CN was
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performed and treated as above to afford compounds 9 (0.47 g,
28%) and 10 (0.25 g, 11% of diastereomeric mixture), as well as
0.47 g of unreacted 4-methoxybenzenesulfonamide and N-(2-
bromo-2-(diphenyl(vinyl)silyl)ethyl)acetamide 14 (0.59 g, 40%)
as a white powder.
Reaction of p-nitrobenzenesulfonamide with diphenyl(di-
vinyl)silane 3 in the presence of NBS in THF. To the solution of
triamide (0.50 g, 3.4 mmol) or p-nitrobenzenesulfonamide
(0.7 g, 3.5 mmol) and equimolar amount of NBS in 50 ml THF
diphenyl(divinyl)silane 3 was added, the mixture was kept for
20 h, THF removed at a reduced pressure, the residue dissolved
in 50 ml of ether, N-succinimide was ltered off, the ltrate
concentrated, the residue separated by column chromatography
eluting successively with hexane and hexane–ether 1 : 1. From
General procedure. To the solution of arensulfonamides
(0.49–1.20 mmol) and equimolar amount of NBS in 15 ml MeCN
compound 12a or 18 (R ¼ Ph) was added and the mixture kept
for 15 h. Then, K2CO3 (0.99–2.30 mmol) was added, the mixture
kept for 4 h, ltered, the solvent removed, the residue dissolved
in 50 ml of ether, N-succinimide ltered off, the ltrate
concentrated, the residue puried by column chromatography
eluting successively with hexane and chloroform. From chlo-
roform
eluate,
2,2,4,4,6,6,8,8-octaphenyl-1,3,5,7,2,4,6,8-
tetraoxatetrasilocane 19 was obtained as white solid in close
to quantitative yield (Table 3).
Reaction of (sulfonyl)acetamidines 13a and 13d with K2CO3.
To the solution of 13a or 13d (0.10–0.27 g, 0.15–0.38 mmol) in
10 ml MeCN two-fold excess K2CO3 was added and stirred for
4 h. The formed precipitate was ltered, solvent removed, the
residue dried in vacuum to give 1,3,5-diazasilinanes 20: 2-
methyl-5,5-diphenyl-1-((triuoromethyl)sulfonyl)-1,3,5-
diazasilinane 20a (R ¼ Ph) 0.058 g (97%), 2-methyl-1-((4-
nitrophenyl)sulfonyl)-5,5-diphenyl-1,3,5-diazasilinane, 20d (R
hexane
eluate,
(1-bromo-2-(4-bromobutoxy)ethyl)
diphenyl(vinyl)silane 15 (R ¼ Ph) was obtained as colorless
oil, from hexane/ether – N-(4-[2-bromo-2-(diphenyl(vinyl)silyl)
ethoxy]butyl)sulfonamides 16, which was puried on ne
silica using hexane and hexane–ether 1 : 2 as eluents to give N-
(4-(2-bromo-2-(diphenyl(vinyl)silyl)ethoxy)butyl)trifamide 16a
(R ¼ Ph) (1.23 g, 74%) or N-(4-(2-bromo-2-(diphenyl(vinyl)silyl)
ethoxy)butyl)-4-nitrobenzenesulfonamide 16d (R ¼ Ph) (1.28 g,
72%).
¼
Ph) 0.164 g (96%), 2,5,5-trimethyl-1-((triuoromethyl)
sulfonyl)-1,3,5-diazasilinane 20a (R ¼ Me) 0.047 (94%).
Reaction of N-(4-[2-bromo-2-(diphenyl- or -dimethyl(vinyl)
silyl)ethoxy]butyl)sulfonamides 16a–d with K2CO3. To the
solution of N-(4-[2-bromo-2-(diphenyl(vinyl)silyl)ethoxy]butyl)
sulfonamides 16a–d (0.120–0.190 g, 0.20–0.35 mmol) in 10 ml
MeCN, two-fold excess of K2CO3 was added and stirred for 4 h.
The formed precipitate was ltered off, solvent removed and the
residue dried in vacuum to give 1,4-oxazocane 21a (0.159 g,
99%) (R ¼ Ph) or 1,4-oxazocane 21d (0.102 g, 98%) (R ¼ Ph).
The reactions of N-(4-[2-bromo-2-(dimethyl(vinyl)silyl)
ethoxy]butyl)sulfonamides 16a–d with K2CO3 and treatment of
the reaction mixtures were performed similarly to give 16a
(0.520 g, 1.26 mmol), 16b (0.300 g, 0.84 mmol), 16c (0.030 g,
0.069 mmol), or 16d (0.220 g, 0.47 mmol). The residue was dried
The reactions with silane 2 and treatment of the reaction
mixture were performed similarly. From hexane eluate, (1-
bromo-2-(4-bromobutoxy)ethyl)dimethyl(vinyl)silane 15 (R ¼
Me) was obtained, from hexane/ether
– N-(4-[2-bromo-2-
(dimethyl(vinyl)silyl)ethoxy]butyl)sulfonamides 16, which was
puried on ne silica using hexane and hexane–ether 1 : 2 as
eluents, and unreacted TfNH2 (0.20 g), or MsNH2 (0.73 g),
TsNH2 (0.68 g), NsNH2 (0.53 g).
Reaction of N-((2-bromo-2-(diphenyl or dimethyl)(vinyl)silyl)
ethyl)sulfonamides 11a, 11c, 11d with K2CO3. To the solution of
11a (0.160 g, 0.35 mmol), 11c (0.143 g, 0.51 mmol) or 11d
(0.137 g, 0.44 mmol) in 5 ml MeCN, 2 equiv. K2CO3 was added,
the obtained mixture stirred for 5 h. The formed precipitate was
ltered, solvent removed, the residue was dried in vacuum to
give of 2-diphenyl- or -dimethyl(vinyl)silyl-1-(sulfonyl)aziridines
17. No reaction of 11a occurred with K2CO3, the reagent was
recovered. Aziridines 17c and 17d are fully characterized in ref.
2.
in
vacuum
to
give
3-(dimethyl(vinyl)
silyl)-4-
(triuoromethylsulfonyl)-1,4-oxazocane 21a (R ¼ Me) (0.411 g,
98%). No reactions occurred with 16b–d (R ¼ Me).
(2-Chloro-1-iodoethyl)diphenyl(vinyl)silane, 4 (R ¼ Ph). Pink
oil. 19% yield. IR (KBr) 3053, 3011, 2938, 1893, 1824, 1655, 1588,
1
1483, 1427, 1296, 1111, 1008, 964, 703, 645, 549, 495 cmꢁ1. H
NMR: 7.69–7.62 (m, CH, 4H), 7.51–7.42 (m, CH, 6H), 6.68 (dd, ]
CH, J 20.2, 14.7 Hz, 1H), 6.39 (dd, ]CHH, J 14.7, 3.2 Hz, 1H),
5.87 (dd, ]CHH, J 20.2, 3.2 Hz, 1H)), 4.05 (dd, J 11.6, 3.3 Hz,
CHAHCl, 1H), 3.91 (dd, J 11.6, 3.3 Hz, CHHBCl, 1H), 3.83 (dd, J
11.6, 10.6 Hz, CHI, 1H). 13C NMR): 138.4 (]CH2), 135.7 (Co),
135.4 (Ci), 132.2 (]CH), 130.3 (Cp), 128.1 (Cm), 49.0 (CH2Cl),
15.9 (CHI). 29Si NMR: ꢁ15.09. Anal. calcd for C6H16ClISi: C,
48.19; H, 4.04; I, 31.83; Cl, 8.89; Si, 7.04. Found: C, 48.11; H,
4.00; I, 31.06; Cl, 8.71; Si, 6.99.
Reaction of N-(2-bromo-2-(diphenyl- or -dimethyl(vinyl)silyl)
ethyl)-N0-(triuoromethylsulfonyl)acetamidine 12a with K2CO3.
To the solution of N-(2-bromo-2-(diphenyl(vinyl)silyl)ethyl)-N0-
(triuoromethylsulfonyl)acetamidine 12a (R ¼ Ph) (0.650 g, 1.29
mmol)
or
N-(2-bromo-2-(dimethyl(vinyl)silyl)ethyl)-N0-(tri-
uoromethylsulfonyl)acetamidine 12a (R ¼ Me) (0.140 g, 0.37
mmol) in 10 ml MeCN, 2 equiv. K2CO3 was added, the obtained
mixture stirred for 4 h. The formed precipitate was ltered,
solvent removed, the residue dried in vacuum to give 5-
(dimethyl(vinyl)silyl)-2-methyl-1-(triuoromethylsulfonyl)-2-
imidazoline 18 (R ¼ Me) (0.106 g, 96%) or 5-(diphenyl(vinyl)
silyl)-2-methyl-1-(triuoromethylsulfonyl)-2-imidazoline 18 (R
¼ Ph) (0.535 g, 98%).
Bis(2-chloro-1-iodoethyl)dimethylsilane, 5 (R ] Me). Dark-
orange oil, crystallizes aer long standing, mp 107 ꢂC. 8%
yield. IR (KBr) 3066, 3018, 2933, 2246, 1963, 1893, 1822, 1588,
1484, 1428, 1294, 1233, 1193, 1112, 1064, 1020, 908, 733, 702,
1
645, 564, 488 cmꢁ1. H NMR: 3.99 (dd, ClCHH, J 11.6, 8.6 Hz,
Reaction of arensulfonamides with 12a and 18 (R ¼ Ph) in
the presence of NBS + K2CO3 in MeCN
2H), 3.93 (dd, ClCHH, J 11.6, 5.0 Hz, 2H), 3.78–3.69 (m, ICH,
2H), 0.49 (s, CH3, 6H, major R,S-diastereomer), 0.462 and 0.457
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(s, CH3, 6H, minor (R,R + S,S)-diastereomer). 13C NMR: major
diastereomer: 47.6 (CH2Cl), 16.7 (CHI), ꢁ3.3 (CH3); minor dia-
stereomer: d 47.9 (CH2Cl), 17.0 (CHI), ꢁ2.1 and ꢁ3.8 (CH3). 29Si
NMR: 9.5, 9.6. Anal. calcd for C6H12Cl2I2Si: C, 16.49; H, 2.77; Cl,
16.23; I, 58.09; Si, 6.43. Found: C, 16.38; H, 2.70; Cl, 16.11; I,
58.25; Si, 6.55.
(1,2-Dibromoethyl)diphenyl(vinyl)silane, 9 (R ¼ Ph). Light-
yellow oil. 0.80 g, 30% yield. IR (KBr) 3053, 3011, 2938, 1824,
1822, 1655, 1588, 1483, 1428, 1122, 1075, 1007, 963, 703, 645,
549, 495 cmꢁ1. 1H NMR: 7.68–7.53 (m, CH (Ph), 4H), 7.53–7.36
(m, CH (Ph), 6H), 6.62 (dd, ]CH, J 19.8, 15.1 Hz, 1H), 6.38 (d, ]
CHH, J 15.1 Hz, 1H), 5.88 (d, ]CHH, J 19.8 Hz, 1H), 4.11 (d,
CHH, J 11.4 Hz, 1H), 4.01 (d, CHH, J 11.4 Hz, 1H), 3.69 (tr, CH, J
11.4 Hz, 1H). 13C NMR: 138.8 (]CH2), 136.2 (Co), 135.7 (Cp),
131.1 (]CH), 130.4 (Ci), 128.2 (Cm), 39.8 (CH2), 37.1 (CH). 29Si
NMR: ꢁ16.4. Anal. calcd for C16H16Br2Si: C, 48.50; H, 4.07; Br,
40.34; Si, 7.09. Found: C, 48.47; H, 4.05; Br, 40.18; Si, 7.00.
Bis(1,2-dibromoethyl)diphenylsilane, 10. Light-yellow oil.
Bis(2-chloro-1-iodoethyl)diphenylsilane, 5 (R ¼ Ph). IR (KBr)
3066, 3018, 2933, 1963, 1893, 1822, 1588, 1484, 1428, 1294,
1233, 1193, 1112, 1064, 1020, 908, 733, 702, 645, 564, 488 cmꢁ1
.
1H NMR: 7.81–7.76 (m, CH, 1H), 7.75–7.66 (m, CH, 3H), 7.60–
7.52 (m, CH, 2H), 7.51–7.43 (m, CH, 4H), 4.33 (dd, J 9.8, 6.1 Hz,
A
A
0
CH H, 1H), 4.29 (dd, J 10.2, 5.8 Hz, CH H, 1H), 3.88 (dd, J 11.8,
B
B
0
5.8 Hz, CHH , 1H), 3.85 (dd, J 11.8, 6.1 Hz, CHH , 1H), 3.66 (dd,
J 11.8, 9.8 Hz, CH, 1H), 3.62 (dd, J 11.8, 10.2 Hz, CH0, 1H). 13C
NMR: 136.6 (Co), 136.5 ðC0 Þ, 131.29 (Cp), 131.21 ðC0 Þ, 131.0 (Ci),
12% yield. IR (KBr) 3064, 2933, 1742, 1700, 1651, 1519, 1425,
1271, 1216, 1115, 1022, 908, 869, 740, 699, 615, 555, 485 cmꢁ1
.
1
H NMR: 7.68 (tr, m-CH, J 7.2 Hz, 2H), 7.56 (d, p-CH, J 7.2 Hz, 1H),
7.48 (tr, o-CH, J 7.2 Hz, 2H), 4.38 (tr, CH, J 10.7 Hz, 1H), 4.37 (tr,
CH, J 10.7 Hz, 1H), 3.94 (tr, CHH, J 4.5 Hz, 1H), 3.92 (tr, CHH, J
4.5 Hz, 1H), 3.51 (tr, CHH, J 10.9 Hz, 1H), 3.46 (tr, CHH, J
10.9 Hz, 1H). 13C NMR: 136.3 (Co), 131.4 (Cp), 128.5 (Cm), 127.1
(Ci), 38.3 (CH), 38.0 (CH), 35.0 (CH2), 34.8 (CH2). 29Si NMR:
ꢁ12.9, ꢁ13.9. Anal. calcd for C16H16Br4Si: C, 34.56; H, 2.90; Br,
57.48; Si, 5.05. Found: C, 34.55; H, 2.85; Br, 57.39; Si, 5.00.
N-(2-Bromo-2-(diphenyl(vinyl)silyl)ethyl)
o
p
0
0
128.4 (Cm), 128.2 ðCmÞ, 47.6 (CH2Cl), 47.3 (CH2 Cl), 16.7 (CHI),
15.7 (CH0I). 29Si NMR: ꢁ14.3, ꢁ14.7. Anal. calcd for C16H16Cl2-
I2Si: C, 34.25; H, 2.87; Cl, 12.64; I, 45.23; Si, 5.01. Found: C,
34.21; H, 2.82; I, 45.02; Cl, 12.19; Si, 4.97.
2-(Diphenyl(vinyl)silyl)-1-(4-nitrophenylsulfonyl)aziridine, 6.
ꢂ
White solid. 20% yield. Mp 109 C. IR (KBr) 3104, 3064, 3009,
1602, 1531, 1427, 1344, 1310, 1206, 1164, 1113, 1009, 960, 898,
856, 815, 747, 695, 617, 548, 497 cmꢁ1. 1H NMR: 8.14 (d, m-CH, J
8.9 Hz, 2H), 7.97 (d, o-CH, J 8.9 Hz, 2H), 7.68–7.54 (m, CH (Ph),
4H), 7.48–7.36 (m, CH (Ph), 6H), 6.30–6.23 (m, ]CH2, 2H), 5.85–
5.74 (m, ]CH, 1H), 2.97 (d, CHHN, J 8.4 Hz, 1H), 2.52 (dd, CHN,
J 8.4, 5.8 Hz, 1H), 2.26 (dd, CHHN, J 5.8 Hz, 1H). 13C NMR:
(mixture of diastereomers) 150.5 (Cp (Ns)), 143.6 (Ci (Ns)),139.0
triuoromethanesulfonamide, 11a (R ¼ Ph). Colorless oil crys-
tallizes upon long standing. 0.76 g, 46% yield. IR (KBr) 3318,
3063, 3016, 2945, 1962, 1896, 1826, 1724, 1592, 1426, 1374,
1197, 1144, 1115, 1073, 1011, 968, 846, 774, 707, 610, 548,
1
505 cmꢁ1. H NMR: 7.68–7.64 (m, CH (Ph), 2H), 7.62–7.57 (m,
(]CH2), 135.4 (Co (Ph)), 135.3 ðC0 ðPhÞÞ, 130.99 (Ci (Ph)), 130.97
CH (Ph), 2H), 7.53–7.48 (m, CH (Ph), 2H), 7.48–7.41 (m, CH (Ph),
4H), 6.58 (dd, ]CH, J 20.1, 14.8 Hz, 1H), 6.41 (dd, ]CHH, J 14.8,
3.3 Hz, 1H), 5.92 (dd, ]CHH, J 20.1, 3.3 Hz, 1H), 5.40 (br. dd,
NH, J 7.5, 2.8 Hz, 1H), 3.95 (dd, CHH, J 12.2, 2.8 Hz, 1H), 3.93
(dd, CHH, J 11.9, 2.8 Hz, 1H), 3.50 (ddd, CH, J 12.2, 11.9, 2.8 Hz,
1H). 13C NMR: (mixture diastereomers) 139.3 (]CH2), 135.77
(Co), 135.70 ðC0 Þ, 130.72 (Cp), 130.71 ðC0 Þ, 130.45 (]CH), 130.2
o
ðC0 ðPhÞÞ, 130.3 (Cp (Ph)), 130.2 ðC0 ðPhÞÞ, 129.1 (]CH), 129.1 (Co
i
p0
(Ns)), 128.18 (Cm (Ph)), 128.14 ðCmðPhÞÞ, 124.0 (Cm (Ns)), 30.3
(CH2), 29.7 (CH). 29Si NMR: ꢁ18.4. Anal. calcd for C22H20N2-
O4SSi: C, 60.53; H, 4.62; N, 6.42; S, 7.34; Si, 6.43. Found: C,
60.48; H, 4.60; N, 6.39; S, 7.22; Si, 6.35.
1-(4-Nitrophenylsulfonyl)-2-((1-(4-nitrophenylsulfonyl)
aziridin-2-yl)diphenylsilyl)aziridine, 7. White solid. 6% yield.
o
p
(Ci), 128.41 (Cm), 128.38 ðC0 Þ, 119.57 (q, J 320.9 Hz, CF3), 47.7
m
(CH2NH), 39.0 (CHBr). 19F NMR: ꢁ77.3. 29Si NMR: ꢁ17.0. Anal.
calcd for C17H17BrF3NO2SSi: C, 43.97; H, 3.69; N, 3.02; Br, 17.21;
S, 6.91; F, 12.27; Si, 6.05. Found: C, 43.93; H, 3.66; N, 2.98; Br,
17.11; S, 6.89; F, 11.98; Si, 5.93.
ꢂ
Mp 178 C. IR (KBr) 3103, 3067, 2924, 2862, 1604, 1530, 1427,
1343, 1204, 1164, 1115, 1085, 951, 901, 857, 818, 739, 696, 617,
503 cmꢁ1. 1H NMR: 8.11 (d, m-CH, J 8.9 Hz, 2H), 7.87 (d, o-CH, J
8.9 Hz, 2H), 7.46–7.34 (m, CH (Ph), 5H), 7.33–7.28 (m, CH (Ph),
3H), 7.24–7.14 (m, CH (Ph), 2H), 2.73 (d, CHHN, J 8.6 Hz, 2H),
2.43 (dd, CHN, J 8.6, 5.8 Hz, 1H), 2.10 (dd, CHHN, J 10.6, 5.8 Hz,
1H). 29Si NMR: 5.5. Anal. calcd for C28H24N4O8S2Si: C, 52.82; H,
3.80; N, 8.80; S, 10.07; Si, 4.41. Found: C, 52.66; H, 3.73; N, 8.69;
S, 9.99; Si, 4.35.
N-(2-Bromo-2-(dimethyl(vinyl)silyl)ethyl)
triuoromethanesulfonamide, 11a (R ¼ Me). Colorless oil.
0.42 g, 39% yield. IR (KBr) 3310, 2960, 1717, 1594, 1427, 1375,
1256, 1233, 1196, 1146, 1072, 1010, 962, 841, 822, 786, 704, 609,
578, 478 cmꢁ1. 1H NMR: 6.1422 (dd, ]CHH, J 14.0, 9.5 Hz, 1H),
6.1421 (dd, ]CH, J 19.3, 14.0 Hz, 1H), 5.85 (ddd, ]CHH, J 19.3,
9.5, 5.7 Hz, 1H), 5.35 (br. s, NH, 1H) 3.79 (ddd, CHAH, J 14.1, 7.6,
2.6 Hz, 1H), 3.47 (ddd, CH, J 14.1, 11.1, 3.2 Hz, 1H), 3.37 (dd,
CHHB, J 11.1, 2.6 Hz, 1H), 0.29 (s, CH3, 3H), 0.28 (s, CH3, 3H).
13C NMR: 135.8 (]CH2), 133.9 (]CH), 119.5 (q, J 318.3 Hz, CF3),
47.6 (CH2N), 41.4 (CHBr), ꢁ4.5 (CH3), ꢁ4.1 (CH3). 19F NMR:
ꢁ77.2. 29Si NMR: ꢁ17.7. Anal. calcd for C7H13BrF3NO2SSi: C,
24.71; H, 3.85; N, 4.12; Br, 23.49; S, 9.42; F, 16.75.
(1,2-Dibromoethyl)dimethyl(vinyl)silane, 9 (R ¼ Me). Color-
less liquid. 0.97 g, 53% yield. IR (KBr) 3052, 3011, 2958, 1593,
1407, 1255, 1212, 1123, 1070, 1029, 1009, 959, 871, 840, 818,
1
789, 708, 628, 596, 542, 513 cmꢁ1. H NMR: 6.19 (dd, ]CH, J
18.8, 14.7 Hz, 1H), 6.12 (dd, ]CHH, J 14.7, 5.2 Hz, 1H), 5.83 (dd,
]CHH, J 18.5, 5.2 Hz, 1H), 3.93 (dd, CHH, J 11.9, 5.4 Hz, 1H),
3.83 (dd, CH, J 11.9, 9.6 Hz, 1H), 3.38 (dd, CHH, J 9.6, 5.4 Hz,
1H), 0.30 (s, CH3, 6H). 13C NMR: 135.0 (]CH2), 134.8 (]CH),
41.9 (CHBr), 36.5 (CH2Br), ꢁ3.8 (CH3), ꢁ4.5 (CH3). 29Si NMR:
ꢁ17.1. Anal. calcd for C6H12Br2Si: C, 26.49; H, 4.45; Br, 58.74; Si,
10.32. Found: C, 26.45; H, 4.44; Br, 58.69; Si, 10.25.
N-(2-Bromo-2-(dimethyl(vinyl)silyl)ethyl)-4-
methylbenzenesulfonamide, 11c (R ¼ Me). Light-yellow oil.
0.49 g, 37% yield. IR (KBr) 3284, 3051, 2956, 2924, 1919, 1597,
40524 | RSC Adv., 2020, 10, 40514–40528
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N-(2-Bromo-2-((1,2-dibromoethyl)diphenylsilyl)ethyl)-N0-
1494, 1406, 1330, 1252, 1161, 1091, 1009, 959, 816, 782, 706,
665, 550 cmꢁ1. 1H NMR: 7.74 (d, m-CH, J 7.9 Hz, 2H), 7.32 (d, o-
CH, J 7.9 Hz, 2H), 6.12–6.06 (m, ]CH2, 2H), 5.77 (ddd, ]CH, J
18.8, 10.3, 5.4 Hz, 1H), 4.88 (br. dd, NH, J 7.1, 4.3 Hz, 1H), 3.47
(ddd, CHH, J 13.6, 7.9, 2.7 Hz, 1H), 3.26 (dd, CHH, J 10.1, 2.7 Hz,
1H), 3.16 (ddd, CH, J 13.6, 10.1, 4.1 Hz, 1H), 2.44 (s, CH3Ph, 3H),
0.217 (s, CH3, 3H), 0.211 (s, CH3, 3H). 13C NMR: 143.7 (Cp), 136.9
(Ci), 135.1 (]CH2), 134.6 (]CH), 129.8 (Cm), 127.1 (Co), 46.4
(CHBr), 41.5 (CH2NH), 21.6 (CH3Ph), ꢁ4.4 (CH3), ꢁ4.9 (CH3).
29Si NMR: ꢁ4.0. Anal. calcd for C13H20BrNO2SSi: C, 43.09; H,
5.56; N, 3.87; Br, 20.05; S, 8.85; Si, 7.75. Found: C, 43.03; H,
5.55; N, 3.82; Br, 19.98; S, 8.80; Si, 7.71.
(triuoromethylsulfonyl)acet-amidine, 13a (R ¼ Ph). Light-
yellow oil crystallizes upon long standing. 60% yield. mp
155 ꢂC. IR (KBr) 3332, 3131, 3071, 2943, 1965, 1894, 1825, 1579,
1552, 1428, 1325, 1209, 1133, 1053, 910, 736, 704, 655, 601,
487 cmꢁ1 1H NMR: (mixture of diastereomers) 7.80–7.62 (m,
.
CH (Ph), 8H), 7.61–7.41 (m, CH (Ph), 12H), 6.47–6.33 (br. m, NH,
1H), 4.52 (dd, J 11.2, 2.9 Hz, 1H), 4.47 (dd, J 10.5, 3.1 Hz, 1H),
4.37–4.31 (m, 2H), 4.26 (ddd, J 14.8, 6.4, 2.9 Hz, 1H), 4.20 (ddd, J
14.8, 5.9, 3.1 Hz, 1H), 3.90 (dd, J 11.2, 4.6 Hz, 1H), 3.86 (dd, J
11.0, 5.1 Hz, 1H), 3.55 (tr, J 10.7 Hz, 1H), 3.49 (tr, J 11.1 Hz, 1H),
3.35 (ddd, J 15.0, 10.3, 4.9 Hz, 1H), 3.18 (ddd, J 14.9, 11.2, 4.5 Hz,
1H), 2.4 (s, CH3, 3H), 2.36 (s, CH3, 3H). 13C NMR: 169.3 (C]N),
169.2 (C]N), 136.2 (Co), 136.1 ðC0 Þ, 131.6 (Cp), 131.5 ðC0 Þ, 128.6
N-(2-Bromo-2-(dimethyl(vinyl)silyl)ethyl)-4-
nitrobenzenesulfonamide, 11d. White solid. 0.14 g, 15% yield.
o
p
(Cm), 128.5 ðC0 Þ, 127.3 (Ci), 127.2 ðC0 Þ, 119.4 (q, J 320.2 Hz, CF3),
ꢂ
mp 106 C. IR (KBr) 3308, 3107, 2957, 1607, 1532, 1405, 1350,
m
i
1312, 1253, 1168, 1091, 1011, 961, 854, 820, 785, 738, 685, 610,
548, 465 cmꢁ1. 1H NMR: 8.38 (d, m-CH, J 8.8 Hz, 2H), 8.06 (d, o-
CH, J 8.8 Hz, 2H), 6.17–6.03 (m, ]CH2, 2H), 5.88–5.74 (m, 1H),
5.15 (br. dd, NH, J 6.9, 3.9 Hz, 1H), 3.56 (ddd, CHH, J 13.1, 7.3,
2.3 Hz, 1H), 3.28 (dd, CHH, J 10.5, 2.3 Hz, 1H), 3.21 (ddd, CH, J
45.3 (CH2NH), 45.1 (CH2NH), 37.6 (CHBr), 36.6 (CHBr), 36.0
(CHBr), 35.8 (CHBr), 34.7 (CH2Br), 34.5 (CH2Br), 21.8 (CH3). 19
F
NMR: ꢁ78.7, ꢁ78.8. 29Si NMR: ꢁ11.1, ꢁ12.2. Anal. calcd for
C
19H20Br3F3N2O2SSi: C, 34.30; H, 3.03; N, 4.21; Br, 36.03; S, 4.82;
F, 8.57; Si, 4.22. Found: C, 34.26; H, 3.00; N, 4.20; Br, 35.88; S,
4.71; F, 8.40; Si, 4.09.
13.1, 10.5, 4.1 Hz, 1H), 0.239 (s, CH3, 3H), 0.231 (s, CH3, 3H). 13
C
N-(2-Bromo-2-((1,2-dibromoethyl)dimethylsilyl)ethyl)-N0-
(triuoromethylsulfonyl)acet-amidine, 13a (R ¼ Me). Light-
yellow oil. 46% yield. IR (KBr) 3040, 2940, 2824, 2546, 2334,
2220, 2120, 1911, 1876, 1704, 1620, 1567, 1490, 1401, 1335,
1250, 1160, 1120, 1000, 950, 811, 773, 706, 544 cmꢁ1. 1H NMR:
6.82 (br. s, NH, 1H), 4.18–4.11 (m, 1H), 3.97–3.88 (m, 1H), 3.86–
3.66 (m, 3H), 3.56–3.45 (m, 1H), 2.53 (s, CH3C]N, 3H), 0.41–
0.33 (m, CH3, 6H). 13C NMR: 168.86 (C]N), 168.80 (C]N),
119.4 (q, J 320.9 Hz, CF3), 45.59 (CH2NH), 45.49 (CH2NH), 38.4
(CHBr), 38.1 (CHBr), 38.8 (CHBr), 37.9 (CHBr), 34.6 (CH2Br),
34.3 (CH2Br), 22.26 (CH3), 22.24 (CH3), ꢁ5.2, ꢁ5.3, ꢁ5.4, ꢁ5.6
(CH3Si). 19F NMR: ꢁ78.9, ꢁ79.0. 29Si NMR: 6.0, 5.7. Anal. calcd
for C9H16Br3F3N2O2SSi: C, 19.98; H, 2.98; N, 5.18; Br, 44.30; S,
5.93; F, 10.53; Si, 5.19. Found: C, 19.97; H, 2.95; N, 5.15; Br,
44.23; S, 5.89; F, 10.41; Si, 5.14.
NMR: 150.2 (Cp), 145.9 (Ci),135.4 (]CH2), 134.2 (]CH), 128.3
(Co), 124.5 (Cm), 46.5 (CHBr), 41.2 (CH2NH), ꢁ4.4 (CH3), ꢁ5.0
(CH3). 29Si NMR: ꢁ3.7. Anal. calcd for C12H17BrN2O4SSi: C,
36.64; H, 4.36; N, 7.12; Br, 20.31; S, 8.15; Si, 7.14. Found: C,
36.63; H, 4.32; N, 7.09; Br, 20.26; S, 8.04; Si, 7.10.
N-(2-Bromo-2-(diphenyl(vinyl)silyl)ethyl)-N0-(tri-
uoromethylsulfonyl)acetamidine, 12a (R ¼ Ph). Light-yellow
oil. 68% yield. IR (KBr) 3333, 3063, 2945, 1582, 1428, 1324,
1210, 1135, 1053, 968, 912, 776, 737, 705, 656, 598, 542,
1
497 cmꢁ1. H NMR: 7.69–7.64 (m, CH (Ph), 2H), 7.63–7.58 (m,
CH (Ph), 2H), 7.50–7.39 (m, CH (Ph), 2H), 6.73 (br. tr, NH, J 4.7,
1H), 6.58 (dd, ]CH, J 20.2, 14.5 Hz, 1H), 6.39 (dd, ]CHH, J 14.5,
3.3 Hz, 1H), 5.91 (dd, ]CHH, J 20.2, 3.3 Hz, 1H), 4.72 (ddd,
CHH, J 14.7, 6.1, 3.0 Hz, 1H), 4.08 (dd, CHH, J 10.9, 3.0 Hz, 1H),
3.50 (ddd, CH, J 14.7, 10.9, 4.7 Hz, 1H), 2.38 (s, CH3, 3H). 13C
NMR: 168.7 (C]N), 139.0 (]CH2), 135.78 (Co), 130.6 (]CH),
130.5 (Cp), 128.5 (Ci), 128.3 (Cm), 119.4 (q, J 319.7 Hz, CF3), 45.9
(CH2NH), 36.6 (CHBr), 22.0 (CH3). 19F NMR: ꢁ79.0. 29Si NMR:
ꢁ16.7. Anal. calcd for C19H20BrF3N2O2SSi: C, 45.15; H, 3.99; N,
5.54; Br, 15.81; S, 6.34; F, 11.28; Si, 5.56. Found: C, 45.14; H,
3.97; N, 5.52; Br, 15.73; S, 6.29; F, 11.08; Si, 5.50.
N-(2-Bromo-2-((1,2-dibromoethyl)diphenylsilyl)ethyl)-N0-(4-
nitrophenylsulfonyl)acetamidine, 13d (R ¼ Ph). Light-yellow oil
ꢂ
crystallizes upon long standing. 60% yield. mp 79 C. IR (KBr)
3309, 3103, 3019, 2926, 1774, 1709, 1529, 1428, 1349, 1290,
1
1148, 1091, 1051, 855, 745, 699, 656, 500, 464 cmꢁ1. H NMR:
8.27 (d, m-CH (Ns), J 8.3 Hz, 2H), 8.04 (d, o-CH (Ns), J 8.3 Hz, 2H),
7.62–7.58 (m, CH (Ph), 2H), 7.52–7.46 (m, CH (Ph), 3H) 7.45–7.32
(m, CH (Ph), 5H), 6.28 (br. tr, NH, J 5.2 Hz, 1H), 4.42 (d, J 10.2,
1H), 4.22 (dd, J 8.7, 3.9 Hz, 1H), 4.10–4.20 (m, 1H), 3.92 (d, J
10.2 Hz, 1H), 3.82–3.72 (m, 1H), 3.30–3.19 (m, 1H), 2.35 (s, CH3,
3H). 13C NMR: (Mixture of diastereomers) 166.5 (C]N), 149.5
(Cp (Ns)), 145.8 (Ci (Ns)), 136.33 (Co (Ph)), 136.31 ðC0oðPhÞÞ,
N-(2-Bromo-2-(dimethyl(vinyl)silyl)ethyl)-N0-(tri-
uoromethylsulfonyl)acetamidine, 12a (R ¼ Me). Light-yellow
oil. 88% yield. IR (KBr) 3332, 2958, 1585, 1560, 1422, 1323,
1254, 1212, 1137, 1052, 961, 844, 823, 773, 740, 660, 598,
1
476 cmꢁ1. H NMR: 6.44 (br. s, NH, 1H), 6.21–6.08 (m, ]CH2,
2H), 5.84 (ddd, ]CH, J 17.4, 11.4, 5.1 Hz, 1H), 4.13 (dd, J 13.4,
6.2 Hz, 1H), 3.47–3.34 (m, 2H), 2.51 (s, CH3C]N, 3H), 0.28 (s,
CH3, 3H), 0.27 (s, CH3, 3H). 13C NMR: 168.6 (C]N), 135.4 (]
CH2), 134.0 (]CH), 119.4 (q, J 319.4 Hz, CF3), 45.9 (CH2N), 39.1
(CHBr), 22.1 (CH3C]N), ꢁ4.8 (CH3), ꢁ5.2 (CH3). 19F NMR:
ꢁ79.2. 29Si NMR: ꢁ3.6. Anal. calcd for C9H16BrF3N2O2SSi: C,
28.35; H, 4.23; N, 7.35; Br, 20.96; S, 8.41; F, 14.95; Si, 7.37.
Found: C, 28.33; H, 4.20; N, 7.34; Br, 20.87; S, 8.34; F, 14.86; Si,
7.29.
131.15 (Cp (Ph)), 131.12 ðC0 ðPhÞÞ, 128.32 (Cm (Ph)), 128.29
p
ðC0 ðPhÞÞ, 128.2 (Ci (Ph)), 127.8 ðC0 ðPhÞÞ, 127.7 (Co (Ns)), 124.1
m
i
(Cm (Ns)), 44.9 (CH2NH), 40.2 (CHBr), 36.2 (CHBr), 29.6 (CH2Br),
21.4 (CH3). 29Si NMR: ꢁ12.9, ꢁ13.9. Anal. calcd for C24H24Br3-
N3O4SSi: C, 40.13; H, 3.37; N, 5.85; Br, 33.37; S, 4.46; Si, 3.91.
Found: C, 40.11; H, 3.36; N, 5.82; Br, 33.27; S, 4.38; Si, 3.87.
N-(2-Bromo-2-(diphenyl(vinyl)silyl)ethyl)acetamide,
14.
White powder. 40% yield. mp 158 ꢂC. IR (KBr) 3415, 3283, 3064,
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2928, 2884, 1653, 1536, 1428, 1366, 1284, 1193, 1145, 1112, 14.89; S, 5.98; F, 10.62; Si, 5.24. Found: C, 47.00; H, 4.65; N, 2.59;
1
1098, 1007, 961, 911, 705, 606, 544, 513 cmꢁ1. H NMR: 7.66– Br, 14.52; S, 5.90; F, 10.30; Si, 5.18.
7.56 (m, CH, 4H), 7.50–7.40 (m, CH, 6H), 6.57 (dd, ]CH, J 20.1,
N-(4-(2-Bromo-2-(diphenyl(vinyl)silyl)ethoxy)butyl)-4-
14.7 Hz, 1H), 6.38 (dd, ]CHH, J 14.7, 3.2 Hz, 1H), 5.92 (br. s, nitrobenzenesulfonamide, 16d (R ¼ Ph). Colorless oil. 72%
NH, 1H), 5.85 (dd, ]CHH, J 20.1, 3.2 Hz, 1H), 3.84 (d.tr, J 9.9, yield. IR (KBr) 3296, 3063, 2940, 2866, 1823, 1601, 1530, 1426,
2.8 Hz, CH, 1H), 3.61–3.49 (m, 1H, CHHN), 3.49–3.39 (m, 1H, 1347, 1164, 1107, 1009, 966, 911, 854, 736, 613, 548, 503,
CHHN), 1.86 (s, CH3, 3H). 13C NMR: 171.7 (C]O), 139.5 (]CH), 466 cmꢁ1. 1H NMR: 8.33 (d, m-CH (Ns), J 8.6 Hz, 2H), 8.05 (d, o-
135.8 (Co), 135.7 ðC0 Þ, 130.7 (Cp), 130.6 ðC0 Þ, 130.2 (Ci), 130.1 CH (Ns), J 8.6 Hz, 2H), 7.68–7.54 (m, CH (Ph), 4H), 7.48–7.36 (m,
o
ðC0 Þ, 130.0 (]CH), 128.5 (Cm), 128.4 ðC0 Þp, 46.2 (CH2N), 42.1 CH (Ph), 6H), 6.58 (dd, ]CH, J 20.3, 14.7 Hz, 1H), 6.34 (dd, ]
i
m
(CHBr), 23.0 (CH3). 29Si NMR: ꢁ18.9. Anal. calcd for C18H20
-
CHH, J 14.7, 3.3 Hz, 1H), 5.84 (dd, ]CHH, J 20.3, 3.3 Hz, 1H),
BrNOSi: C, 57.75; H, 5.39; N, 3.74; Br, 21.34; Si, 7.50. Found: C, 5.32 (br. tr, NH, J 5.7 Hz, 1H), 3.39 (dd, J 8.9, 3.0 Hz, 1H), 3.87
46.37; H, 4.31; N, 4.79; Br, 3.83; Si, 7.50.
(dd, J 11.3, 3.0 Hz, 1H), 3.70 (dd, J 11.3, 8.9 Hz, 1H), 3.44–3.32
(1-Bromo-2-(4-bromobutoxy)ethyl)diphenyl(vinyl)silane, 15 (m, 2H), 3.11–2.95 (m, 2H), 1.62–1.51 (m, 4H). 13C NMR: 149.9
(R ¼ Ph). Colorless oil. Yield 18–21%. IR (KBr) 3053, 3008, 2942, (Cp (Ns)), 146.2 (Ci (Ns)), 138.1 (]CH2), 135.7 (Co), 131.8 (]CH),
2861, 1962, 1895, 1825, 1725, 1656, 1590, 1429, 1364, 1255, 131.7 (Ci), 130.1 (Cp), 128.3 (Co (Ns)), 128.0 (Cm), 124.3 (Cm (Ns)),
1193, 1111, 1007, 962, 706, 652, 549, 501 cmꢁ1. 1H NMR: 7.70– 72.8 (CHCH2O), 70.3 (OCH2CH2), 43.1 (CH2N), 37.5 (CHBr), 27.1
7.59 (m, CH (Ph), 4H), 7.47–7.37 (m, CH (Ph), 6H), 6.62 (dd, ] (OCH2CH2), 26.6 (CH2CH2N). 29Si NMR: ꢁ16.5. Anal. calcd for
CH, J 20.4, 14.7 Hz, 1H), 6.34 (dd, ]CHH, J 14.7, 3.5 Hz, 1H),
C26H29BrN2O5SSi: C, 52.97; H, 4.96; N, 4.75; Br, 13.55; S, 5.44; Si,
5.84 (dd, ]CHH, J 20.4, 3.5 Hz, 1H), 3.95 (dd, J 8.0, 3.5 Hz, 1H), 4.76. Found: C, 52.95; H, 4.93; N, 4.70; Br, 13.46; S, 5.39; Si, 4.68.
3.88 (dd, J 11.1, 3.5 Hz, 1H), 3.76 (dd, J 11.1, 8.0 Hz, 1H), 3.46–
N-(4-(2-Bromo-2-(dimethyl(vinyl)silyl)ethoxy)butyl)
3.37 (m, 4H), 1.95–1.86 (m, 2H), 1.72–1.66 (m, 2H). 13C NMR: triuoromethanesulfonamide, 16a (R ¼ Me). Colorless oil.
(Mixture of diastereomers) 137.7 (]CH2), 135.85 (Co), 135.82 1.98 g, 89% yield. IR (KBr) 3313, 2952, 2872, 1594, 1434, 1374,
ðC0 Þ, 132.3 (]CH), 132.18 (Ci), 132.07 ðC0 Þ, 130.06 (Cp), 130.05 1253, 1231, 1192, 1150, 1105, 1010, 958, 842, 822, 783, 702, 610,
o
i
ðC0 Þ, 127.97 (Cm), 127.96 ðC0 Þ, 72.8 (CHCH2O), 69.8 (OCH2CH2), 578, 514 cmꢁ1. H NMR: 6.16 (dd, ]CH, J 19.3, 14.7 Hz, 1H),
1
p
m
37.1 (CHBr), 37.1 (CHBr), 33.9 (CH2Br), 29.5 (OCH2CH2), 28.1 6.08 (dd, ]CHH, J 14.7, 4.5 Hz, 1H), 5.96 (br. tr, NH, J 5.3 Hz,
(CH2CH2Br). 29Si NMR: ꢁ20.0. Anal. calcd for C20H24Br2OSi: C, 1H), 5.79 (dd, ]CHH, J 19.3, 4.5 Hz, 1H), 3.83 (dd, J 11.3, 3.4 Hz,
51.30; H, 5.17; Br, 34.13; Si, 6.00. Found: C, 51.27; H, 5.10; Br, 1H), 3.69 (dd, CHBr, J 11.3, 9.2 Hz, 1H), 3.57–3.43 (m, 2H), 3.42–
33.85; Si, 5.76.
3.33 (m, 3H), 1.77–1.71 (m, CH2CH2, 4H), 0.25 (s, CH3, 3H), 0.24
(1-Bromo-2-(4-bromobutoxy)ethyl)dimethyl(vinyl)silane, 15 (s, CH3, 3H). 13C NMR: 135.3 (]CH), 134.2 (]CH2), 119.8 (q, J
(R ¼ Me). Colorless liquid. Yield 8–52%. IR (KBr) 3050, 2946, 321.3 Hz, CF3), 72.8 (CHCH2O), 70.3 (OCH2CH2), 44.0 (CH2N),
2867, 1593, 1478, 1439, 1406, 1356, 1251, 1110, 1009, 956, 841, 39.7 (CHBr), 27.6 (OCH2CH2), 26.4 (CH2CH2N), ꢁ4.3 (CH3),
822, 780, 648, 610, 561, 515 cmꢁ1. H NMR: 6.17 (dd, ]CH, J ꢁ4.8 (CH3). 19F NMR: ꢁ77.3. 29Si NMR: ꢁ4.6. Anal. calcd for
1
19.8, 14.7 Hz, 1H), 6.06 (dd, ]CHH, J 14.7, 4.0 Hz, 1H), 5.78 (dd,
C11H21BrF3NO3SSi: C, 32.04; H, 5.13; N, 3.40; Br, 19.38; S, 7.78;
]CHH, J 19.8, 4.0 Hz, 1H), 3.80 (dd, J 11.1, 4.0 Hz, 1H), 3.71 (dd, F, 13.82; Si, 6.81. Found: C, 32.01; H, 5.12; N, 3.35; Br, 19.29; S,
CHBr, J 11.1, 8.0 Hz, 1H), 3.55–3.42 (m, 4H), 3.39 (dd, CHBr, J 7.70; F, 13.73; Si, 6.74.
8.0, 4.0 Hz, 1H), 2.01–1.94 (m, 2H), 1.77–1.70 (m, CH2CH2, 2H),
N-(4-(2-Bromo-2-(dimethyl(vinyl)silyl)ethoxy)butyl)
0.247 (s, CH3, 3H), 0.244 (s, CH3, 3H). 13C NMR: 135.9 (]CH), methanesulfonamide, 16b (R ¼ Me). Light-yellow oil. 0.17 g,
133.9 (]CH2), 73.0 (CHCH2O), 69.9 (OCH2CH2), 39.9 (CHBr), 17% yield. IR (KBr) 3289, 2948, 2868, 1733, 1593, 1558, 1541,
33.8 (CH2Br), 29.7 (OCH2CH2), 28.2 (CH2CH2N), ꢁ4.0 (CH3), 1408, 1321, 1252, 1153, 1109, 1010, 972, 841, 823, 782, 702, 611,
ꢁ4.4 (CH3). 29Si NMR: ꢁ4.3. Anal. calcd for C10H20Br2OSi: C, 522 cmꢁ1. H NMR: 6.13 (dd, ]CH, J 19.7, 14.7 Hz, 1H), 6.03
1
34.90; H, 5.86; Br, 46.43; Si, 8.16. Found: C, 34.87; H, 5.85; Br, (dd, ]CHH, J 14.7, 4.1 Hz, 1H), 5.75 (dd, ]CHH, J 19.7, 4.1 Hz,
46.39; Si, 8.13.
1H), 4.88 (br. s, NH, 1H), 3.77 (dd, J 11.2, 3.6 Hz, 1H), 3.66 (dd,
CHBr, J 11.2, 8.5 Hz, 1H), 3.48–3.37 (m, 3H), 3.15–3.09 (m, 2H),
N-(4-(2-Bromo-2-(diphenyl(vinyl)silyl)ethoxy)butyl)
triuoromethanesulfonamide, 16a (R ¼ Ph). Colorless oil. 74% 2.92 (s, CH3SO2, 3H), 1.67–1.62 (m, CH2CH2, 4H), 0.208 (s, CH3,
yield. IR (KBr) 3320, 3061, 2943, 2868, 1962, 1898, 1827, 1709, 3H), 0.204 (s, CH3, 3H). 13C NMR: 135.5 (]CH), 133.9 (]CH2),
1591, 1429, 1371, 1193, 1112, 966, 860, 709, 609, 549, 503 cmꢁ1
.
72.7 (CHCH2O), 70.1 (OCH2CH2), 42.8 (CH2N), 40.0 (CH3SO2),
1H NMR: 7.66–7.57 (m, CH (Ph), 4H), 7.46–7.39 (m, CH (Ph), 39.9 (CHBr), 27.0 (OCH2CH2), 26.5 (CH2CH2N), ꢁ4.2 (CH3),
6H), 6.59 (dd, ]CH, J 20.3, 14.7 Hz, 1H), 6.35 (dd, ]CHH, J 14.7, ꢁ4.6 (CH3). 29Si NMR: ꢁ4.4. Anal. calcd for C11H24BrNO3SSi: C,
3.2 Hz, 1H), 5.84 (dd, ]CHH, J 20.3, 3.2 Hz, 1H), 5.75 (br. tr, NH, 36.87; H, 6.75; N, 3.91; Br, 22.30; S, 8.95; Si, 7.84. Found: C,
J 5.1 Hz, 1H), 3.97–3.88 (m, 2H), 3.75 (dd, J 10.8, 8.9 Hz, 1H), 36.86; H, 6.74; N, 3.89; Br, 22.26; S, 8.92; Si, 7.77.
3.48–3.41 (m, 2H), 3.34–3.25 (m, 2H), 1.71–1.64 (m, 4H). 13C
N-(4-(2-Bromo-2-(dimethyl(vinyl)silyl)ethoxy)butyl)-4-
NMR: (mixture of diastereomers) 138.1 (]CH2), 135.78 (Co), methylbenzenesulfonamide, 16c (R ¼ Me). Colorless oil. 0.72 g,
135.74 ðC0 Þ, 131.80 (]CH), 131.85 (Ci), 131.76 ðC0 Þ, 130.16 (Cp), 35% yield. IR (KBr) 3283, 2947, 2868, 1720, 1598, 1407, 1328,
o
i
130.15 ðC0 Þ, 128.04 (Cm), 128.02 ðC0 Þ,119.7 (q, J 321.3 Hz, CF3), 1251, 1161, 1095, 1010, 956, 841, 818, 782, 664, 552 cmꢁ1. H
1
p
m
72.9 (CHCH2O), 70.4 (OCH2CH2), 44.0 (CH2N), 36.9 (CHBr), 27.7 NMR: 7.75 (d, m-CH, J 7.9 Hz, 2H), 7.29 (d, o-CH, J 7.9 Hz, 2H),
(OCH2CH2), 26.4 (CH2CH2N). 19F NMR: ꢁ77.1. 29Si NMR: ꢁ16.8. 6.15 (dd, ]CH, J 19.6, 14.6 Hz, 1H), 6.05 (dd, ]CHH, J 14.6,
Anal. calcd for C21H25BrF3NO3SSi: C, 47.01; H, 4.70; N, 2.61; Br, 4.2 Hz, 1H), 5.77 (dd, ]CHH, J 19.6, 4.2 Hz, 1H), 4.88 (br. tr, NH,
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J 5.9 Hz, 1H), 3.76 (dd, J 11.3, 3.8 Hz, 1H), 3.65 (dd, CHBr, J 11.3, (tr, m-CH, J 7.5 Hz, 2H), 7.18 (tr, o-CH, J 7.5 Hz, 4H). 13C NMR:
8.5 Hz, 1H), 3.46–3.35 (m, 3H), 3.02–2.92 (m, 2H), 2.43 (s, 134.5 (Ci), 134.4 (Cm), 130.0 (Cp), 127.6 (Co). 29Si NMR: ꢁ43.1.
CH3Ph, 3H), 1.61–1.54 (m, CH2CH2, 4H), 0.228 (s, CH3, 3H), Anal. calcd for C48H40O4Si4: C, 72.68; H, 5.08; Si, 14.16. Found:
0.221 (s, CH3, 3H). 13C NMR: 143.2 (Cp), 137.1 (Ci), 135.7 (] C, 72.66; H, 5.07; Si, 14.11.
CH2), 134.0 (]CH), 129.6 (Cm), 127.1 (Co), 72.8 (CHCH2O), 70.2
2-Methyl-5,5-diphenyl-1-(triuoromethylsulfonyl)-1,3,5-
(OCH2CH2), 42.9 (CH2N), 32.9 (CHBr), 26.7 (OCH2CH2), 26.6 diazasilinane, 20a (R ¼ Ph). Light-yellow oil. 97% yield. IR (KBr)
(CH2CH2N), 21.5 (CH3Ph), ꢁ4.1 (CH3), ꢁ4.5 (CH3). 29Si NMR: 2959, 1668, 1554, 1400, 1259, 1201, 1153, 1084, 1052, 961, 914,
ꢁ4.4. Anal. calcd for C17H28BrNO3SSi: C, 47.00; H, 6.50; N, 3.22; 835, 802, 673, 615, 587, 533 cmꢁ1
.
1H NMR: 7.47 (d, o-CH, J
Br, 18.39; S, 7.38; Si, 6.46. Found: C, 46.98; H, 6.47; N, 3.20; Br, 7.3 Hz, 4H), 7.34 (tr, p-CH, J 7.3 Hz, 2H), 7.18 (tr, m-CH, J 7.3 Hz,
18.31; S, 7.34; Si, 6.40.
4H), 4.03–3.85 (m, CHCH2, 4H), 2.27 (br. s, CH3, 3H). 13C NMR:
153.6 (C]N), 134.5 (Ci (Ph)), 134.4 (Cm (Ph)), 130.0 (Cp (Ph)),
N-(4-(2-Bromo-2-(dimethyl(vinyl)silyl)ethoxy)butyl)-4-
nitrobenzenesulfonamide, 16d (R ¼ Me). Light-yellow oil. 127.6 (Co (Ph)), 121.5 (q, J 322.3 Hz, CF3), 52.8 (CH2), 48.9 (CH2),
1.42 g, 80% yield. IR (KBr) 3292, 2948, 2869, 1607, 1531, 1349, 16.1 (CH3). 19F NMR: ꢁ75.0. 29Si NMR: ꢁ43.0. Anal. calcd for
1311, 1251, 1165, 1093, 1012, 958, 852, 822, 781, 736, 686, 611,
C17H17F3N2O2SSi: C, 51.24; H, 4.30; N, 7.03; S, 8.05; F, 14.30; Si,
563 cmꢁ1. 1H NMR: 8.35 (d, m-CH, J 8.9 Hz, 2H), 8.06 (d, o-CH, J 7.05. Found: C, 51.18; H, 4.19; N, 7.18; S, 8.11; F, 14.70; Si, 7.11.
8.9 Hz, 2H), 6.14 (dd, ]CH, J 19.2, 14.7 Hz, 1H), 6.06 (dd, ] 2-Methyl-1-(4-nitrophenylsulfonyl)-5,5-diphenyl-1,3,5-
CHH, J 14.7, 4.6 Hz, 1H), 5.78 (dd, ]CHH, J 19.2, 4.6 Hz, 1H), diazasilinane, 20d (R ¼ Ph). Yellow solid. 96% yield. mp 171 ꢂC.
5.40 (br. tr, NH, J 5.9 Hz, 1H), 3.78 (dd, J 11.3, 3.4 Hz, 1H), 3.64 IR (KBr) 3067, 2934, 2879, 1657, 1596, 1532, 1429, 1357, 1235,
(dd, CHBr, J 11.3, 9.1 Hz, 1H), 3.47–3.36 (m, 3H), 3.12–3.01 (m, 1172, 1119, 1020, 970, 927, 857, 739, 696, 612, 580, 526, 495,
2H), 1.67–1.60 (m, CH2CH2, 4H), 0.23 (s, CH3, 3H), 0.22 (s, CH3, 464 cmꢁ1. 1H NMR: 8.42 (d, m-CH, J 8.6 Hz, 2H), 8.07 (d, o-CH, J
3H). 13C NMR: 149.9 (Cp), 146.3 (Ci), 135.4 (]CH), 134.2 (] 8.06 Hz, 2H), 7.47 (d, o-CH, J 7.3 Hz, 4H), 7.33 (tr, p-CH, J 7.3 Hz,
CH2), 128.3 (Co), 124.3 (Cm), 72.8 (CHCH2O), 70.3 (OCH2CH2), 2H), 7.17 (tr, m-CH, J 7.3 Hz, 4H), 3.77 (br. s, CH2, 4H), 2.30
43.1 (CH2N), 40.2 (CHBr), 27.1 (OCH2CH2), 26.7 (CH2CH2N), (br. s, CH3, 3H). 13C NMR: 155.0 (C]N), 150.5 (Cp (Ns)), 144.1
ꢁ4.1 (CH3), ꢁ4.6 (CH3). 29Si NMR: ꢁ4.5. Anal. calcd for C16- (Ci (Ns)), 134.4 (Ci (Ph)), 134.3 (Co (Ns)), 130.0 (Cp (Ph)), 128.4
H25BrN2O5SSi: C, 41.29; H, 5.41; N, 6.02; Br, 17.17; S, 6.89; Si, (Cm (Ph)), 127.6 (Cm (Ns)), 124.8 (Co (Ph)), 52.3 (CH2NNs), 48.2
6.03. Found: C, 41.28; H, 5.37; N, 6.00; Br, 17.13; S, 6.78; Si, 5.94. (CH2), 16.8 (CH3). 29Si NMR: ꢁ42.8. Anal. calcd for C22H21N3-
5-(Dimethyl(vinyl)silyl)-2-methyl-1-(triuoromethylsulfonyl)- O4SSi: C, 58.52; H, 4.69; N, 9.31; S, 7.10; Si, 6.22. Found: C,
2-imidazoline, 18 (R ¼ Me). Yellow oil. 96% yield. IR (KBr) 3055, 58.60; H, 4.73; N, 9.40; S, 7.14; Si, 6.25.
2960, 2877, 1674, 1594, 1403, 1386, 1286, 1255, 1237, 1203,
2,5,5-Trimethyl-1-(triuoromethylsulfonyl)-1,3,5-
1153, 1087, 1052, 1010, 992, 958, 916, 842, 825, 782, 704, 678, diazasilinane, 20a (R ¼ Me). Yellow oil. 94% yield. IR (KBr)
661, 616, 584, 537, 520 cmꢁ1. 1H NMR: 6.14–5.99 (m, 2H), 5.87– 2961, 1671, 1557, 1403, 1261, 1204, 1155, 1087, 1056, 962, 916,
5.72 (m, 1H), 4.06–3.98 (m, 1H), 3.89–3.78 (m, 2H), 2.22 (s, CH3, 839, 803, 675, 617, 588, 535 cmꢁ1. 1H NMR: 4.05–3.72 (m, CH2,
3H), 0.21 (s, CH3, 3H), 0.18 (s, CH3, 3H). 13C NMR: 154.7 (C]N), 4H), 2.25 (br. s, CH3, 3H), 2.22 (s, CH3, 3H), 0.25–0.20 (m, CH3,
135.2 (]CH2), 133.9 (]CH), 121.5 (q, J 325.2 Hz, CF3), 56.2 6H). 13C NMR: 154.6 (C]N), 55.6 (CH2NTf), 53.3 (CH2), 16.6
(CH2), 53.2 (CH), 16.6 (CH3), ꢁ5.2 (CH3), ꢁ6.0 (CH3). 19F NMR: (CH3), ꢁ1.3 (CH3), ꢁ1.4 (CH3), ꢁ1.95 (CH3), ꢁ1.97 (CH3). 19F
ꢁ73.9. 29Si NMR: ꢁ17.8. Anal. calcd for C9H15F3N2O2SSi: C, NMR: ꢁ74.1. 29Si NMR: ꢁ41.3. Anal. calcd for C7H13F3N2O2SSi:
35.99; H, 5.03; N, 9.33; S, 10.68; F, 18.97; Si, 9.35. Found: C, C, 30.65; H, 4.78; F, 20.78; N, 10.21; S, 11.69; Si, 10.24. Found: C,
35.97; H, 5.02; N, 9.31; S, 10.56; F, 18.88; Si, 9.29.
30.70; H, 4.83; N, 10.25; S, 11.64; F, 20.85; Si, 10.27.
5-(Diphenyl(vinyl)silyl)-2-methyl-1-(triuoromethylsulfonyl)-
3-(Diphenyl(vinyl)silyl)-4-(triuoromethylsulfonyl)-1,4-
2-imidazoline, 18 (R ¼ Ph). Yellow oil. 98% yield. IR (KBr) 3061, oxazocane, 21a (R ¼ Ph). Yellow oil. 94% yield. IR (KBr) 3055,
3016, 2949, 2877, 1963, 1896, 1826, 1673, 1589, 1557, 1401, 2939, 2863, 1961, 1895, 1824, 1591, 1429, 1367, 1241, 1199,
1
1
1286, 1203, 1152, 1113, 960, 918, 790, 708, 614, 506 cmꢁ1. H 1112, 1006, 964, 910, 706, 614, 548, 505 cmꢁ1. H NMR: 7.69–
NMR: 7.48–7.38 (m, CH (Ph), 5H), 7.37–7.23 (m, CH (Ph), 5H), 7.55 (m, 5H), 7.41–7.34 (m, 5H), 6.58 (dd, ]CH, J 20.3, 14.7 Hz,
6.54 (dd, ]CH, J 20.3, 14.7 Hz, 1H), 6.20 (dd, ]CHH, J 14.7, 1H), 6.31 (dd, ]CHH, J 14.7, 3.3 Hz, 1H), 5.83 (dd, ]CHH, J
3.3 Hz, 1H), 5.65 (dd, ]CHH, J 20.3, 3.3 Hz, 1H), 4.36 (dd, CHH, 20.3, 3.3 Hz, 1H), 3.99 (dd, J 9.2, 2.9 Hz, 1H), 3.85 (dd, J 11.5,
J 10.4, 3.6 Hz, 1H), 4.0–3.9 (m, CHH, 1H), 3.83 (dd, CH, J 15.2, 2.9 Hz, 1H), 3.70 (dd, J 11.5, 9.2 Hz, 1H), 3.40–3.35 (m, 1H),
3.3 Hz, 1H), 1.86 (s, CH3, 3H). 13C NMR: 154.7 (C]N), 138.7 (] 3.34–3.26 (m, 1H), 2.98 (tr, J 6.1 Hz, 2H), 1.56–1.42 (m, 4H). 13
C
CH2), 135.7 (Co), 134.5 (Ci), 134.3 (Ci), 130.8 (]CH), 130.4 (Cp), NMR: 138.0 (Ci), 135.8 (]CH2), 135.7 (Co), 131.9 (]CH), 130.1
130.3 (Cp), 128.2 (Cm), 128.1 (Cm), 120.1 (q, J 325.8 Hz, CF3), 56.5 (Cp), 128.0 (Cm), 122.1 (q, CF3, J 326.9 Hz), 72.6, 70.7, 44.9, 37.6,
(CH2), 52.4 (CH), 16.3 (CH3). 19F NMR: ꢁ74.0. 29Si NMR: ꢁ15.2. 29.0, 26.9. 19F NMR: ꢁ76.6. 29Si NMR: ꢁ16.5. Anal. calcd for
Anal. calcd for C19H19F3N2O2SSi: C, 53.76; H, 4.51; N, 6.60; S,
C21H24F3NO3SSi: C, 55.37; H, 5.31; N, 3.07; S, 7.04; F, 12.51; Si,
7.55; F, 13.43; Si, 6.62. Found: C, 53.74; H, 4.49; N, 6.55; S, 7.51; 6.16. Found: C, 55.33; H, 5.28; N, 3.07; S, 7.00; F, 12.32; Si, 6.08.
F, 13.02; Si, 6.58.
3-(Diphenyl(vinyl)silyl)-4-(4-nitrophenylsulfonyl)-1,4-
2,2,4,4,6,6,8,8-Octaphenyl-1,3,5,7,2,4,6,8-
oxazocane, 21d (R ¼ Ph). Yellow oil. 98% yield. IR (KBr) 3070,
tetraoxatetrasilocane, 19. White solid. 97–99% yield. mp 184 ꢂC. 2943, 2868, 1606, 1530, 1428, 1349, 1311, 1166, 1109, 1012, 965,
IR (KBr) 3052, 2925, 2855, 1962, 1892, 1739, 1428, 1122, 1075, 854, 737, 701, 612, 547, 503, 464 cmꢁ1. 1H NMR: 8.32 (d, m-CH
1
700, 524, 489 cmꢁ1. H NMR: 7.48 (d, o-CH, J 7.5 Hz, 4H), 7.35 (Ns), J 8.7 Hz, 2H), 8.04 (d, o-CH (Ns), J 8.7 Hz, 2H), 7.65–7.57 (m,
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CH (Ph), 4H), 7.47–7.38 (m, CH (Ph), 6H), 6.58 (dd, J 20.3,
14.7 Hz, ]CH, 1H), 6.34 (dd, J 14.7, 3.3 Hz, ]CHH, 1H), 5.83
(dd, J 20.3, 3.3 Hz, ]CHH, 1H), 3.95 (dd, J 8.8, 2.9 Hz, 1H), 3.87
(dd, J 11.3, 2.9 Hz, 1H), 3.70 (dd, J 11.3, 8.8 Hz, 1H), 3.42–3.33
(m, 2H), 3.07–2.99 (m, 2H), 1.60–1.55 (m, 4H). 13C NMR: 150.0
(Cp (Ns)), 146.3 (Ci (Ns)), 138.1 (]CH2), 135.8 (Co), 131.9 (]CH),
131.8 (Ci), 130.2 (Cp), 128.3 (Co (Ns)), 128.0 (Cm), 124.3 (Cm (Ns)),
72.8, 70.4, 43.1, 37.5, 27.2, 26.7. 29Si NMR: ꢁ16.6. Anal. calcd for
References
1 W. P. Weber, in Silicon Reagents for Organic Synthesis, ed. W.
P. Weber, Springer Berlin, Heidelberg, 1983, pp. 1–430.
2 D. S. W. Lim and E. A. Anderson, Synthesis, 2012, 44, 983–
1010.
3 B. Marciniec and C. Pietraszuk, Curr. Org. Chem., 2003, 7,
691–735.
4 A. Barbero and F. J. Pulido, Acc. Chem. Res., 2004, 37, 817–
C
26H28N2O5SSi: C, 61.39; H, 5.55; N, 5.51; S, 6.30; Si, 5.52.
Found: C, 61.36; H, 5.51; N, 5.49; S, 6.22; Si, 5.45.
825.
3-(Dimethyl(vinyl)silyl)-4-(triuoromethylsulfonyl)-1,4-
oxazocane, 21a (R ¼ Me). Colorless oil. 98% yield. IR (KBr) 3053,
2946, 2866, 2793, 1637, 1594, 1456, 1407, 1364, 1252, 1201,
1154, 1083, 1009, 987, 958, 910, 842, 822, 782, 735, 615,
5 T. A. Blumenkopf and L. E. Overman, Chem. Rev., 1986, 86,
857–873.
´
6 (a) P. Pawluc, W. Prukała and B. Marciniec, Eur. J. Org. Chem.,
2010, 2010, 219–229; (b) J. Szudkowska-Fr˛atczak,
1
515 cmꢁ1. H NMR: 6.16 (dd, ]CH, J 19.6, 14.7 Hz, 1H), 6.06
´
G. Hreczycho and P. Pawluc, Org. Chem. Front., 2015, 2,
(dd, ]CHH, J 14.7, 4.2 Hz, 1H), 5.78 (dd, ]CHH, J 19.6, 4.2 Hz,
1H), 3.78 (dd, J 11.1, 3.4 Hz, 1H), 3.67 (dd, J 11.1, 9.6 Hz, CH,
1H), 3.50–3.40 (m, 3H), 3.06–2.99 (m, 2H), 1.63–1.49 (m, 4H),
0.24 (s, CH3, 3H), 0.23 (s, CH3, 3H). 13C NMR: 135.5 (]CH2),
134.1 (]CH), 122.0 (q, CF3, J 328.0 Hz), 72.6 (CHCH2O), 70.7
(OCH2CH2), 45.0, 40.3, 29.0, 27.0, ꢁ4.2 (CH3), ꢁ4.6 (CH3). 19F
NMR: ꢁ77.3. 29Si NMR: ꢁ4.5. Anal. calcd for C11H20F3NO3SSi: C,
39.86; H, 6.08; N, 4.23; S, 9.67; F, 17.20; Si, 8.47. Found: C, 39.85;
H, 6.05; N, 4.22; S, 9.61; F, 17.09; Si, 8.43.
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Conflicts of interest
There are no conicts of interests to declare.
Acknowledgements
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This work was performed using the equipment of the Baikal
Analytical Center for Collective Use of Siberian Branch of
Russian Academy of Sciences.
40528 | RSC Adv., 2020, 10, 40514–40528
This journal is © The Royal Society of Chemistry 2020