The addition of SF5Br to acrylic esters: Pathways to γ-SF5-propane derivatives

Article abstract of DOI:10.1016/S0022-1139(99)00249-3

Reaction of SF₅Br with various acrylic esters, CH₂CHCOOR, where R=C₂H₅/C(CH₃)₃ and CH₂C(CH₃)COOCH₃, CH₂C(CH₂Cl)-COOC₂H₅, CH₂C(n-C₇H₁₅)COOC₂H₅ resulted in 1:1 adducts with the SF₅-group attached to the CH₂ portion of the acrylic ester. These adducts were converted to halogen-free saturated esters, an alcohol [SF₅(CH₂)₃OH] an acid [SF₅(CH₂)₂COOH] and a bromide [SF₅(CH₂)₃Br]. Therefore, a method for chain-elongation of SF₅-aliphatic hydrocarbons has been devised. With ethyl acrylate, a 2:1 adduct was also isolated. The reaction of SF₅Cl with (C₂H₅O)₂CCHCOOC₂H₅ gave chloromalonate. The compounds were characterized by their infrared, nuclear magnetic and mass spectral data.

Full text of DOI:10.1016/S0022-1139(99)00249-3

Journal of Fluorine Chemistry 102 (2000) 79±87
The addition of SF5Br to acrylic esters: pathways to
g-SF5-propane derivatives
R. Winter, G.L. Gard*
Department of Chemistry, Portland State University, Portland, OR 97207, USA
Received 15 June 1999; received in revised form 7 July 1999; accepted 20 August 1999
Dedicated to Professor Paul Tarrant on the occasion of his 85th birthday
Abstract
Reaction of SF5Br with various acrylic esters, CH2=CHCOOR, where R ˆ C2H5/C(CH3)3 and CH2=C(CH3)COOCH3, CH2=C(CH2Cl)-
COOC2H5, CH2=C(n-C7H15)COOC2H5 resulted in 1:1 adducts with the SF5-group attached to the CH2 portion of the acrylic ester. These
adducts were converted to halogen-free saturated esters, an alcohol [SF5(CH2)3OH] an acid [SF5(CH2)2COOH] and a bromide
[SF5(CH2)3Br]. Therefore, a method for chain-elongation of SF5-aliphatic hydrocarbons has been devised. With ethyl acrylate, a 2:1 adduct
was also isolated. The reaction of SF5Cl with (C2H5O)2C=CHCOOC2H5 gave chloromalonate. The compounds were characterized by their
infrared, nuclear magnetic and mass spectral data. # 2000 Elsevier Science S.A. All rights reserved.
Keywords: Penta¯uorosulfanyl; Fluoroesters; Synthesis; IR/NMR/MS spectroscopy
SF5Br
SF5Br
‡
CH2ˆCꢀCH2Cl†COOC2H5
1. Introduction
!
SF5CH2CBrꢀCH2Cl†COOC2H5
(3)
(4)
3
As part of our research program dealing with SF5-organo
derivatives, the addition of SF5Br to acrylic esters was
investigated in the hope that the resulting SF5-ester products
would give either by an elimination of HBr an SF5-contain-
ing acrylate or that the resulting SF5-esters might be con-
verted to intermediates useful for preparation of chain-
lengthened propane derivatives. Previously, the addition
of SF5Cl to ethyl acrylate and the addition of SF5Br to
ethyl acrylate and ethyl b-acetoxy acrylate have been
reported [1,2].
‡
CH2ˆCꢀn-C7H15†COOC2H5
!
SF5CH2CBrꢀn-C7H15†COOC2H5
4
Previously, we found that SF5Br readily adds to ethyl
acrylate (neat, mild heat) to give compound
5
(SF5CH2CHBrCOOC2H5), while with ethyl b-acetoxy acry-
late in CCl3F irradiation was needed for addition [2]. By
using an inert solvent (Freon-113) which was employed in
all but one of the above reactions (Eq. (4)), good yields were
generally obtained. For large-scale additions of SF5Br to
ethyl acrylate, a method was adopted whereby the acrylic
ester and SF5Br were condensed in portions into the reaction
vessel and warmed intermittently in order to avoid over-
heating. This procedure gave a signi®cantly improved yield
of 5 (80%) over that previously obtained (36%). For the t-
butyl ester of acrylic acid (Eq. (1)) it was observed, that
SF5Br addition was very slow at room temperature but was
complete by heating to ꢁ608C overnight. For the other
reactions listed above, heating was used in order to ensure
completeness of the reactions. Interestingly, examination of
the distillation residue of the reaction of ethyl acrylate with
SF5Br resulted in the isolation of a 2:1 adduct of monomer
2. Results and discussion
We have found that the new SF5-containing ester deriva-
tives (1±4) can be prepared using the appropriate acrylate
precursor via the following pathway:
SF5Br
‡
CH2ˆCHCOOCꢀCH3†
3
!
SF5CH2CHBrCOOCꢀCH3†
(1)
(2)
3
1
SF5Br
‡
CH2ˆCꢀCH3†COOCH3
!
SF5CH2CBrꢀCH3†COOCH3
2
* Corresponding author. Fax: ‡1-503-7253888.
0022-1139/00/$ ± see front matter # 2000 Elsevier Science S.A. All rights reserved.
PII: S 0 0 2 2 - 1 1 3 9 ( 9 9 ) 0 0 2 4 9 - 3

80
R. Winter, G.L. Gard / Journal of Fluorine Chemistry 102 (2000) 79±87
and SF5Br, compound 6; the adduct accounts for about 5%
of the SF5Br used.
The reduction of the SF5-esters adducts 1 and 5 with tri(n-
butyl)tin hydride gave the corresponding esters 7 and 8:
other example of a similar carbon chain arrangement is
1-chloro-4-(pentafluorothio)butane which was obtained by
a pressure reaction of SF5Cl with an excess of ethylene [4].
In our continuing studies of SF5X (X ˆ Cl, Br) reactions
with ole®ns, the reaction of ethyl b,b-diethoxyacrylate (in
Freon-113) was studied as a potential pathway to SF5-
containing malonic esters. The main product was diethyl
chlormalonate (13), 97% yield by gas chromatography; SF4
and ethyl ¯uoride were also observed by 19F NMR spectro-
scopy. The SF5-adduct, which was expected to be
SF5CH(COOC2H5)2, was not detected. The formation of
chlormalonic ester (13), from ethyl b,b-diethoxyacrylate
implies that SF5-attack would either have been at the b-
position of the ester, with subsequent destruction of the SF5-
adduct, or reaction occurred by a different route involving
R03SnH
SF5CH2CHBrCOOR
!
SF5CH2CH2COOR
R ˆ CH3CH2 7 or
(5)
CꢀCH3† 8
3
The acid hydrolysis of the esters 7 and 8 gave the corre-
sponding SF5-substituted propionic acid 9; for the SF5-t-
butyl ester derivative, the hydrolysis was rapid and gave a
pure product. The ethyl ester required longer reaction time
and was accompanied by the formation of pitchy decom-
position products even though the ester cleavage was not yet
complete:
‡
only transfer of the elements of Cl and F and accom-
panied by loss of SF4. In the latter case, the intermediate a-
¯uoroacetal would be expected to easily lose ethyl ¯uoride.
‡
H
; heat
8
!
SF5CH2CH2COOH
9
(6)
The reduction of compound 4 was studied. The forma-
tion of a new SF5-compound was apparent by GC±MS
analysis and 19F NMR spectroscopy. Due to a slow and
incomplete reaction, accompanied by loss of SF5, this
reaction was not further examined. The reduction of com-
pound 3 resulted in replacement of the bromine atom:
(10)
Previously, we have observed that with the related b-acet-
oxy acrylate attack was at the a position and resulted in the
formation of an SF5Br-adduct. Attempts to add SF5X to a
malonic ester, triethyl methanetricarboxylate (keto±enol
equilibrium) or to a malonyl chloride (ketene±acyl chloride)
[5] were unsuccessful. Also attempts to add SF5X to ethyl a-
(iododmercurimethyl) acrylate, and ethyl b-ethoxy-b-tri-
methylsilyloxyacrylate resulted in loss of SF4. With diethyl
cyclopropane-1,1-dicarboxylate which behaves in some
aspect as an olefin [6] no SF5-incorporation was observed
with SF5Br (heating 2 weeks, 908C in CCl2FCClF2). How-
ever, diethyl glutaconate, ethyl b-bromoacrylate and ethyl
vinylacetate were found to slowly react; in all cases, several
SF5-signals (19F NMR spectroscopy) were observed after
prolonged heating (up to 3 weeks at 80±908C). These
reactions were not further considered. It is thus clear that
there is a certain reactivity range of the olefinic bond which
allows for successful SF5-halide addition. This addition is
limited by low reactivity on one side and high reactivity
(electron-rich olefins) on the other side; high reactivity
results in halogen halide addition and SF4-expulsion.
The infrared spectra for all new compounds have in
common the characteristic absorption bands of the SF5
group. Cross and coworkers reported that the most intense
band for compounds containing the SF5 grouping should
appear in the region 850±920 cm 1 (S±F stretching modes)
and in the region of 600 cm 1 (S±F deformation modes) [7].
For the new compounds reported in this paper, the stretching
absorption bands are found in the 817±894 region while the
(7)
In addition to the acid hydroysis studies, further reduc-
tion of SF5CH2CH2COOR with BH3Á(CH3)2S in tetrahy-
drofuran was carried out; a procedure developed by Brown
et al. [3]. The ethyl ester 7 was reduced in a clean reaction
and led after hydrolysis to 3-SF5-propanol while the t-butyl
ester 8 gave a mixture which consisted of only a small
amount of 3-SF5-propanol; the identity of the major com-
ponent was not ascertained due to dif®culties in separating
the two compounds, but the GC±MS suggests it to be
SF5CH2CH2CH2OC(CH3)3.
1:BH3ÁꢀCH3†2S
2:H2O
SF5CH2CH2COOCH2CH3
!
SF5CH2CH2CH2OH
11
(8)
This alcohol was readily converted to the bromide:
PBr3
!
SF5CH2CH2CH2OH
SF5CH2CH2CH2Br
12
(9)
In a subsequent experiment it was found that using methy-
lene chloride as the extraction solvent led to higher recovery
rates of the alcohol (85%) and the solution was more readily
dried with magnesium sulfate. The twofold reduction of
SF5CH2CHBrCOOC2H5 therefore represents a systematic
method of obtaining 3-SF5-1-propyl derivatives. The only
1
deformation band is located in the 576±600 cm region.
The C±H and carbonyl vibrations were found respectively in
1
the 3051±2772 and the 1719±1755 cm region.

R. Winter, G.L. Gard / Journal of Fluorine Chemistry 102 (2000) 79±87
81
The 19F NMR spectra showed no signi®cant deviations
from the chemical shifts or coupling constants found for
other aliphatic derivatives of sulfur hexa¯uoride. The che-
mical shifts of the apical ¯uorine atom (fA) in the SF5-
group were in the range of 81±86 ppm, while the basal
¯uorines were observed at 64±68 ppm (fB), with the typical
appearance of the AB4-spin system, JAB ˆ 144±151 Hz. 1H
NMR spectroscopy allowed for complete interpretation at
500 MHz but spectra at 90 MHz were in most cases used for
qualitative assignments due to their complexity. At
500 MHz it was observed that the SF5-substituted CH2-
group appeared as an AX- or AB-type spin system with
dA,B ˆ 3.8±4.8 ppm, JAB ꢁ 11±14 Hz and usually exhibited
different couplings of the SF5CH2 protons with the basal
¯uorine atoms of the SF5-group, ranging from 7.33±
8.20 Hz. In the ethyl and t-butyl ester of a-bromo-b-SF5-
propionic acid, an AB-spin system was formed by Ha and
Hb instead, while Hb and Hb' formed an AX-system. After
reduction of the bromides to derivatives of either propionic
acid or propane, the asymmetry was removed; b-CH2 (g-
CH2 for the propane derivatives) was then observed as a
septet or a triplet of a pentet, since JH H ꢁ JH FB, while a-
Fig. 1. Ethyl a-bromo-b-chloro-b0-SF5-isobutyrate structure.
was further split into a quartet (for OCH2) or asymmetrically
by the neighboring CH2-group (for CH2(CH2)5CH3), while
CH2Cl showed only the AB-quartet; this is illustrated with
the H NMR spectrum of ethyl a-bromo-b-chloro-b0-SF5-
isobutyrate (Fig. 2). This effect was absent from the reduced
product, ethyl b-SF5-b0-chloroisobutyrate, and only the SF5-
bearing methylene group retained its appearance as an AB-
type spectrum.
1
3. Experimental section
a
b
b
CH2 was a triplet and interpretation was possible with ®rst-
order rules. Of particular interest were the 1H NMR spectra
of ethyl 2-bromo-2-(penta¯uorothiomethyl)pelargonate and
of ethyl a-bromo-b-chloro-b0-SF5-isobutyrate (Fig. 1); at
90 MHz the signals for the groupings OCH2 and SF5CH2
were overlapped multiplets, while at 500 MHz, in addition
to the SF5-bearing methylene group, both the methylene
group of the ethyl group as well as the heptyl methylene that
connects the chain to Ca and the CH2Cl-group attached to
Ca had to be interpreted as an AB-system, where each line
3.1. Starting materials
Ethyl n-heptacrylate was obtained by the Mannich pro-
cedure [8] which starts from diethyl malonate. After alkyla-
tion with n-heptyl bromide and partial hydrolysis to the half-
ester of n-heptylmalonic acid, the latter is treated with the
Mannich reagent ((C2H5)2NH ‡ formalin), which leads by
concomitant decarboxylation to the formation of the ester of
the a-alkylated acrylic acid. This compound has been made
previously by the ethyl diethylphosphonoacetate method
1
Fig. 2. H NMR spectrum (CDCl3, 500 MHz) of ethyl a-bromo-b-chloro-b0-SF5-isobutyrate [not shown is the CH3 group (triplet)].

82
R. Winter, G.L. Gard / Journal of Fluorine Chemistry 102 (2000) 79±87
[9±10]. Our yield is comparable to that obtained by employ-
ing the latter route. Ethyl (a-chloromethyl)acrylate was
vw; 647, vw; 619, vw; 576, m; 564, m; 518, vw; 441, vw.
‡
GC-MS: Rt ˆ 8.1 min: 319, 321, (M CH3) , each 6%;
‡
‡
‡
Â
obtained using the Villiaeras and Rambaud method [11];
127, SF5 , 9%; 89, SF3 , 7%; 57, CꢀCH3†3 , 100%. Anal.
calcd. for C7H12BrF5O2S: C, 25.09; H, 3.61;Br, 23.84.
Found: C, 25.01; H, 3.52; Br, 24.38%.
the synthesis of ethyl b,b-diethoxyacrylate used the Glick-
man and Cope method [12]. Diethyl n-heptylmalonate was
prepared according to published procedures [13,14].
For NMR spectroscopy the ¯uorine standard ˆ CCl3F;
proton and carbon standard ˆ Si(CH3)4. Instruments used
were either a Varian EM 390 (1H at 90 MHz, 19F at
84.67 MHz) or a Nicolet NT 500 (500 MHz). Abbreviations
used are, s, singlet; d, doublet; t, triplet; q, quartet; p, pentet.
All gas chromatography Ð mass spectra, unless indicated
otherwise, were run on a HP5890 Series II gas chromato-
graph with a DB5 column (length ˆ 12 m), coupled to a
HP5970 mass-selective detector (ionization energy is
70 eV). The temperature program was such that t ˆ 508C
for 4 min, then the temperature was raised to 2808C at 188C/
min.; total run time was 25 min. Infrared spectra were
recorded from thin ®lms of the pure substances with a
Nicolet DX 20 instrument and the following abbreviations
are used: w, weak; m, medium; s, strong; v, very; sh,
shoulder and combinations following from these. Volatile
materials (esters of low boiling point, 1-,1-,2-trichlorotri-
¯uoroethane (Freon-113), SF5Br and SF5Cl) were trans-
3.3. t-Butyl-b-SF5-propionate (8)
To a solution of t-butyl a-Br-b-SF5-propionate (9.66 g,
28.8 mmol) in 150 ml (C2H5)2O in a 500 ml round-bottom
¯ask, stirred in a water bath at room temperature, 10.4 g of
(n-C4H9)3SnH (35.5 mmol) was added dropwise. After 1 h
another 0.75 g of the reductant was added; the reaction was
complete after 24 h. The solid tin products were ®ltered off
and after removal of the solvent, distillation at 58±618C,
5.5±6.0 Torr, gave 6.62 g, yield ˆ 89.6%, of a colorless,
oily product.
1H NMR spectrum (CDCl3, 500 MHz): dt-butyl
ˆ
1.46 ppm, s, 9.0 H; da ˆ 2.82, t, 2.0 H; db ˆ 3.95, septet,
2.0 H, Jab ꢁ JbFB ˆ 7.81 Hz. 19F NMR spectrum (CDCl3,
84,7 MHz), AB4: jA ˆ 84.3 ppm (nine lines), 1.0 F;
jB ˆ 64. 4 ppm (skewed d-m), 4.0 F, JAB ˆ 148.2 Hz.
Infrared spectrum (neat sample, KBr): 3037, w; 2984, m-
s; 2938, m; 2877, w-m; 2827, vw; 1733, vs; 1479, m; 1459,
m; 1422, m-s; 1396, m-s; 1370, s; 1349, m-w; 1280, m-s;
1250, s; 1156, vs; 1074, w; 1024, w-m; 985, m; 945, w; 924,
w; 888, s-vs; 837, vs; 754, m; 670, vw; 596, m-s; 565, m;
541, w; 512, vw; 440, w-vw. GC±MS, Rt ˆ 7.21 min: 241,
ferred by way of vacuum condensation at 1968C.
Elemental analysis was carried out by: Mikroanalytisches
È
Laboratorium Beller, Gottingen, Deutsche Bundesrepublik.
‡
‡
3.2. t-Butyl a-Br-b-SF5-propionate (1)
(M CH3) , 3%; 183, (M ‡ H±C(CH3)3) , 14%; 127,
‡
‡ ‡
SF5 , 14%; 89, SF3 , 17%; 57, CꢀCH3†3 , 100%. Anal. calcd.
for C7H13F5O2S: C, 32.81; H, 5.11; F, 32.07; S, 12.51.
Found: C, 33.03; H, 5.34; F, 32.9; S, 12.38%.
t-Butyl acrylate (6.30 g, 49.2 mmol) was vacuum-trans-
ferred ( 1968C) into a 75 ml steel bomb tube containing
80 g of Freon-113. After thawing and mixing, SF5Br
(13.68 g, 66.1 mmol) was added at 1968C. The reaction,
kept at room temperature overnight, was warmed at 55±
608C for 19 h. The tube contents were distilled, ®rst at
atmospheric pressure to remove the solvent, then at 68±
748C, 4±6 Torr, yielding 11.24 g (68.2% yield) of a slightly
oily, colorless product.
3.4. b-SF5-propionic acid (9)
5.00 g (19.5 mmol) of t-butyl-b-SF5 propionate and
15 ml of conc. HCl were heated with stirring at 80±908C
in a 50 ml round-bottom ¯ask equipped with a re¯ux
condenser for 1 h; stirring was continued for another 2 h
without heating. The ¯ask contained a mobile upper and an
oily, slightly brown, lower layer. After storing in the freezer
overnight, the oil crystallized. It was suction-®ltered and
washed with a little water, sucked dry and subjected to
sublimation at ca. 508C and ꢁ20 m, with the cooling water
held at ‡48C; rather quickly, 2.94 g of white, hard crystals
were obtained. Since initially an oily hue was observed on
the cold ®nger, the sublimation was repeated without heat-
ing (cold ®nger still at ‡48C) and interrupted after a while
when the oily hue had formed again, to rinse it off, then
continued. The material that was then collected was sub-
limated again; obtained were 2.66 g of hard white crystals.
Another 0.45 g of product were obtained by extracting
(2 Â 5 ml of CH2Cl2) the ®ltrate above and sublimating the
evaporation residue. Yield 3.11 g or 79.6 %. m.p. 47±488C.
1H NMR spectrum (500 MHz, CDCl3): da ˆ 2.96 ppm, t,
J ˆ 7.21 Hz, 2.06; db ˆ 3.95 ppm, septet, J ˆ 7.58 Hz
1H NMR spectrum (CDCl3, 500 MHz): db ˆ 4.51
0
asymmetrical d-p; db ˆ 3.98, d-p; da ˆ 4.57, asymmetrical
d-d; dt-butyl ˆ 1.34, s; hydrogens a ‡ b form an AB-system,
0
a ‡ b:b: t-butyl ˆ 1.9:1.0:9.0 H.; Jbb ˆ 14.19 Hz,
0
0
Jab ˆ 11.73; Jab ˆ 2.93; JbFB ˆ 7.33; db FB ˆ 8.06;
19F NMR spectrum (CDCl3, 84.7 MHz), AB4:
jA ˆ 81.7 ppm (nine lines), 1.0 F; jB ˆ 65.7 ppm (skewed
d-m), 4.0 F, JAB ˆ 144.0 Hz. Infrared spectrum (neat sam-
ple, KBr): 3041,w; 3006, w,sh; 2985, m; 2940, w; 2916,
w,sh; 2878, vw; 1746, s-vs; 1477, w-m; 1458, w-m; 1416,
m; 1397, m; 1372, m-s; 1314, m-s; 1279, m; 1251, m-s;
1148, s-vs; 1084, w; 1043, w; 989, m-s; 927, w; 876, s-vs;
841, vs; 836, vs; 805, m-s; 767, m; 755, vw; 694, vw; 674,

R. Winter, G.L. Gard / Journal of Fluorine Chemistry 102 (2000) 79±87
83
(JbFB ꢁ Jab), 2.04 H; d ˆ 11.11, broad s, 1.0 H, COOH. 19
F
NMR spectrum (84.7 MHz, CDCl3): AB4 specrtum:-
jA ˆ 84.1 ppm, nine lines, 1.0 F. jB ˆ 64.7 ppm, skewed
d-m, JAB ˆ 147.4 Hz, 4.0 F.
3.6. Ethyl a-bromo-b-SF5-propionate (5) and (6)
A 175 ml steel bomb tube containing 70 ml of Freon-113
was charged with 4.18 g of ethyl acrylate (at 1968C) then
warmed and shaken. Then, 9.06 g of SF5Br were added
( 1968C). This mixture was shaken, after liquefaction of
the contents, and kept at 08C for ca. 15 min. This procedure
for adding, mixing and reacting was repeated with portions
of ethyl acrylate (7.66, 4.68, 5.94 g, respectively) and SF5Br
(15.06, 15.69, 1.42 g, respectively). The container was then
kept at room temperature for 1 day and warmed to 55±608C
for 2 h. After distilling away the solvent at atmospheric
pressure, vacuum distillation (10 Torr, 73±748C) of the
residue gave 49.5 g of product (yield of 81%) from a total
of 22.46 g of ethyl acrylate (224.6 mmol) and 41.23 g of
SF5Br (199.2 mmol) [2].
13C NMR spectrum, H-decoupled (100 MHz, CDCl3,
Si(CH3)4 ˆ 0): dCO ˆ 176.4 ppm, s. da ˆ 31.18 ppm, s.
db ˆ 65.90 ppm, pentet, JbFB ˆ 16.09 Hz. Infrared spec-
trum (neat sample, KBr): Broad feature, ca. 3500±2500,
of medium strength, with further bands on it; 3051, m; 2975,
w-m; 2916, w-m; 2772, vw; 2690, w; 2611,w; 2580, w;
1719, s-vs; 1440, m-s; 1428, m; 1412, m-s; 1356, vw; 1332,
w-m; 1263, m-s; 1240, m-s; 1187, w-m; 1065, w; 976, m;
944, m; 930, w-m; 848, vs; 817, vs; 669, vw; 649, w-m; 610,
w-m; 596, m; 575, w; 563, w-m; 546, w-m; 517, w. GC±MS:
‡
‡
Rt ˆ 7.28 min: 200, 0.3%, m ; 183, 11%, (m OH) ; 180,
‡
‡
‡
4%, (M HF) ; 127, SF5 , 17%; 108, 8%, SF4 ; 89, 95%,
SF3 ; 45, COOH . Anal. calcd. for C3H5F5O2S: C, 18.01; H,
2.52; F, 47.5; S, 16.02. Found: C, 18.20; H, 2.44; F, 47.9; S,
16.20%.
1H NMR spectrum (500 MHz, CDCl3); designations are
as with t-butyl a-bromo-b-SF5-propionate above: db ˆ 4.57
‡
‡
0
d-p-d, 1.0 H; db ˆ 4.02, d-p-d, 1.0 H; da ˆ 4.67, d-d;
dCH ˆ 1.32, t, 2.8 H; dCH ˆ 4.38, q, 2.0 H; dCH
ˆ
CH2
3
3
2
3.5. Methyl a-bromo-b-SF5-isobutyrate (2)
7.11 Hz. Protons a and b form an AB spin system
0
0
with Jab ˆ 11.33 Hz; Jab ˆ 2.93 Hz, Jbb ˆ 13.32 (from
0
0
Methyl methacrylate (2.54 g, 25.4 mmol) in Freon -113
(10 ml) in a 75 ml steel bomb tube was treated with SF5Br
(5.07 g, 24.5 mmol); ®rst it was kept at ambient temperature
for 1 week, then at 408C for 20 h, ®nally at 55±608C for 2 h.
After cooling and opening the bomb, the contents were
transferred to a 25 ml distillation ¯ask (the reaction vessel
was rinsed with a Freon-113), and the solvent was distilled
off at ambient pressure. The product was obtained by short-
path distillation as a limpid liquid, 6.60 g, b.p. 58±58.58C at
12.0±12.5 Torr. Yield ˆ 88%. In another run on a similar
scale, with the conditions of room temperature, 3 d, 558C, 5
d, the yield was 73%.
Hb -signal), JbFB ˆ 7.20, Jb FB ˆ 7.81 Hz. GC±MS: Rt ˆ
‡
6.85 min: 263, 261, (m-OC2H5) , each 0.6%; 181, 179,
(m SF5) , each 2.6%; 155, 153, CH=CHBrCOF ‡
‡
‡
‡
(rearr.), 8.1, 6.9%; 127, SF5 , 8.5%; 125, C3H2F2OS ,
‡
‡
4.8%; 108, 106, C2H3Br , 17.3, 17.5%; 89, SF4 , 10.4%;
‡
‡
‡
‡
73, COOC2H5 , 3.5%; 70, SF2 , 2.5%; 55, C3H3O , 32%;
‡
45, C2H5O , 7.7%; 29, C2H5 , 100%.
Also obtained were 6.23 g of oily residue. The material
was found to have the following properties: Oily, colorless
liquid, boiling range 96±1038C (dynamic vacuum).
1H NMR spectrum (500 MHz, CDCl3): Multiplets were
observed at dmiddle ꢁ 1.4 (6 H); d ꢁ 2.1±2.5 (2 H); ꢁ3.2 (0.5
H); d ꢁ 3.4 (0.5 H); d ꢁ 3.8 (1 H); d ꢁ 4.3 ppm (6 H). 19F
NMR spectrum (84.7 MHz, CDCl3): AB4 specrtum: jA ˆ
84.0 ppm, nine lines,broadened, 1.06 F. jB ˆ 66.7 ppm,
skewed d-m, 3.93 F, JAB ˆ 144.9 Hz. Infrared spectrum
(neat sample, KBr): 3023 vw,sh; 2987, w; 2944, vw; 2914,
vw; 2890, vw; 1739, s-vs; 1473, w,sh; 1468, w; 1444, m-w;
1420, w; 1380, m; 1319, w; 1278, m; 1264, m-s; 1232, m,sh;
1182, m-s; 1159, m,sh; 1114, w,sh; 1101, w-m; 1041, m;
1025, m; 926, vw; 877, m-s; 841, vs; 826, vs; 788, vw; 706,
vw; 635, m; 600, w-m; 572, w. Anal. calcd. for
C10H16BrF5O4S: C, 29.50; H, 3.96; Br, 19.62. Found: C,
29.72; H, 3.83; Br, 19.51%, and was assigned the structure
of ethyl a-bromo-g-carbethoxy-d-SF5-valerate, the 2:1
adduct of ethyl acrylate and SF5Br.
1H NMR spectrum (500 MHz, CDCl3): d1 ˆ 2.15 ppm, s,
2.8 H (a-CH3). d2 ˆ 3.84 ppm, s, 2.8 H (OCH3); SF5CH2
appeared as an AB-system with each of the four lines
coupled to the equatorial ¯uorine atoms of the SF5-group
with dA ˆ 4.08 ppm, d-p, (1.0 H), dB ˆ 4.76 ppm, d-p, (1.0
H), JAB ˆ 13.48 Hz, JAFB ˆ 8.20 Hz, JBFB ˆ 7.80 Hz. 19F
NMR spectrum (84.7 MHz, CDCl3): AB4 specrtum:-
jA ˆ 82.7 ppm, nine lines, 1.0 F. jB ˆ 67.6 ppm, skewed
d-m, 4.0 F, JAB ˆ 150.6 Hz. Infrared spectrum (neat sample,
NaCl): 3044, w-vw; 3010, vw; 2986, vw; 2959, w; 2850,
vw; 1755, s; 1459, m; 1438, w-m; 1417, w; 1391, w-m;
1320, m; 1307, m-s; 1254, m; 1225, m-s; 1198, w-m,sh;
1182, m; 1120, s; 1070, m; 996, w-m; 938, w-m; 890, m-s;
873, m-s; 827, vs; 785, w; 656, vw. GC±MS: Rt ˆ 7.30 min:
‡
‡
‡
306, 308, m , 0.5%; 227, (m Br) , 8%; 151, SF5C2 ,
‡
4.5%; 141, 139, C4H2Br , 12.7, 14.2%; 137, 135,
‡
3.7. Ethyl b-SF5-propionate (7)
‡
CBrCOO , 14.8, 13.7%; 127, SF5 , 5.7%; 122, 120,
‡
‡
C3H5Br , 22.7, 21.6%; 108, SF4 , 2.0%; 99, (m SF5Br±
‡
To 12.28 g (40 mmol) of ethyl a-Br-b-SF5-propionate in
a 50 ml cylindrical ¯ask, cooled in a room temperature
water bath, 11.93 g (41 mmol) of (n-C4H9)3SnH was added
dropwise with swirling within ꢂ10 min. The ¯ask was
lightly capped and the contents were stirred overnight after
‡
‡
‡
H) , 5.7%; 89, SF3 , 21.5%; 70, SF2 ,CCOOCH2 , 4.9%; 69,
‡
‡
CH3C(CH2)CO , 27.3%; 59, CCOOCH3 , 100%. Anal.
calcd. for C5H8BrF5O2S: C, 19.56; H, 2.63; Br, 26.05.
Found: C, 20.06; H, 2.68; Br, 26.27%.

84
R. Winter, G.L. Gard / Journal of Fluorine Chemistry 102 (2000) 79±87
which another 2.28 g of tin reagent was added and the
mixture stirred for another day. The mixture was ®ltered
and the ®lter cake was washed with 10 ml of ether; the
®ltrate was transferred to a 100 ml round-bottom ¯ask and
distilled through a 12 cm Vigreux column at 9.5±10.5 Torr.
The fraction boiling at 65±688C was collected (6.97 g, yield
was 76.4%).
1482, w-m,sh; 1452, m; 1435, m; 1296, vw; 1239, vw; 1170,
w-m; 1059, m-s; 925, m-s; 864, s,sh; 825, vs; 791, m-s,sh;
763, w,sh; 693, w-m; 665, vw; 632, m-s; 598, m; 565, m;
470, w; 431, w.
‡
‡
GC±MS: 127, 3.6%, SF5 ; 119, 5.2%, (SF3C2H4 ‡ 2H) ;
‡
‡
‡
89, 28.6%, SF3 ; 70, 3.1%, SF2 ; 59, 5.2%, C3H7O ; 58,
‡
‡
‡
11.3%, C3H6O ; 57, 10.2%, C3H5O ; 41, 12.2%; C3H5 ;
‡
1H NMR spectrum (90 MHz, CDCl3): dCH ˆ 1.29 ppm,
39, 5.6%, C3H3 ; 31, 100%, CH2OH . Anal. calcd. for
C3H7F5OS: C, 19.36; H, 3.79; F, 51.0; S, 17.22. Found:
C, 20.22; H, 3.76; F, 52.4; S, 18.20%.
‡
3
t, 3.0 H; dOCH ˆ 4.27 ppm, quartet, JCH
ˆ 7.36 Hz;
CH3
2
2
da ˆ 2.95, t, 1.9 H; db ˆ 4.08 ppm, t-p, Jab ˆ 7.65 Hz;
JbFB ˆ 7.90 Hz, (partial overlap: OCH2 ‡ Hb ˆ 4.0 H).
19FNMR spectrum (84.7 MHz, CDCl3): AB4 spectrum:-
jA ˆ 84.0 ppm, nine lines, 1.0 F. jB ˆ 64.5 ppm, skewed
d-m, 4.0 F, JAB ˆ 144.5 Hz. Infrared spectrum (neat sam-
ple, KBr): 3039, vw; 2990, w-m; 2946, vw-w; 2912, vw;
2880, vw; 1741, s; 1475, w,sh; 1470, w; 1450, w-m,sh;
1424, w-m; 1380, m; 1359, w-m; 1335, w-m; 1290, m; 1223,
m; 1202, m; 1170, m; 1111, vw,sh; 1098, w; 1075, w; 1038,
w-m,sh; 1023, w-m; 980, w-vw; 943, w-vw; 889, m-s; 833,
vs; 800, w-vw,sh; 669, vw; 610, w-m; 595, m; 565, w-m;
547, w-vw. GC±MS. (DB5, 25 m): Rt ˆ 7.74 min 183, 63%,
3.9. 1-Brom-3-SF5-propane (12)
Phosphorus tribromide, 1.20 g, was added in two equal
portions with swirling to 2.32 g of 3-SF5-propanol dissolved
in 5 ml of ether; the mixture came to a boil and expelled
HBr. After keeping it at room temperature for 24 h, the
reaction was quenched with ꢁ5 ml of water in an ice bath;
the lower layer which separated was removed; the aqueous
phase was extracted with 5 ml of ether and the combined
organic phases were distilled through a cold trap ( 1968C).
A pale tan-colored liquid, boiling range of 72±758C at
42 Torr (2.47 g, yield of 80%) was obtained. The product
was dried with P4O10 (48C overnight) and isolated by
vacuum transfer.
‡
‡
‡
(m C2H5O) ; 181, 24%, (m C2H5±H2O) ; 127, 14%,
‡
‡
SF5 ; 101, 12%, (m SF5) ; 89, 77%, SF3 ; 75, 52%,
‡
‡
‡
C2FS ; 73, 20%, COOC2H5 ; 56, 19%, C3H4O ; 55,
‡
‡
22%, C3H3O ; 47, 62%, (SCH2 ‡ H) ; 45, 21%,
‡
‡
‡
C2H5O ; 29, 100%, C2H5 ; 28, 46%, (C2H4, CO) ; 27,
50%, C2H3 ; 26, 11%, C2H2 . Anal. calcd. for C5H9F5O2S:
C, 26.32; H, 3.98; F, 41.6. Found: C, 26.47; H, 4.06; F,
41.8%.
1H NMR spectrum (500 MHz, CDCl3): d1 ˆ 3.45 ppm, t,
J12 ˆ 6.35 Hz, 1.9 H, CH2Br. d2 ˆ 2.47, pentet, broadened
(or t-t), Japparent ꢁ 6.9 Hz (about the average of J23 and J12),
2.0 H. d3 ˆ 3.85 ppm, t-p, J23 ˆ J3FB ˆ 7.81 Hz, SF5CH2,
2.0 H. 19F NRM spectrum (84.7 MHz, CDCl3): AB4 spec-
trum:jA ˆ 84.7 ppm, nine lines, 1.0 F. jB ˆ 65.7 ppm,
skewed d-m, JAB ˆ 148.7 Hz, 4.0 F. Infrared spectrum (neat
sample, KBr): 3021, vw; 2978, w; 2941, vw; 2869, vw;
1746, vw; 1466, w, sh; 1446, m; 1443, m; 1431, m; 1367,
vw; 1314, vw; 1296, w; 1255, s; 1218, vw; 1198, vw; 1176,
vw; 1150, w; 1072, w; 1022, w; 989, vw; 979, vw; 882, s-vs;
823, vs; 790, m-s, sh; 767, m; 718, w; 691, w; 665, w; 657,
vw; 632, s; 599, m-s; 590, m; 572, m; 565, m-s; 546, w-m.
‡
‡
3.8. 3-SF5-propanol (11)
Ethyl-SF5-propionate (8.0 g, 35 mmol) and 29 ml of a
2.0 M solution of BH3Á(CH3)2S (58 mmol) in tetrahydro-
furan were mixed together in a lightly stoppered ¯ask for 1
day, after which more of the BH3Á(CH3)2S solution (20 ml)
was added. The reaction was complete (4 day) and the
mixture was hydrolyzed with ice cooling by adding 100 ml
of 1 N K2CO3 solution and 100 ml of water. The upper oily
layer was separated and the aqueous phase extracted
(3 Â 15 ml of ether); the combined organic phases were
washed with water (50 ml), and extracted with ether
(2 Â 10 ml). The organic phases were combined and dried
over Na2SO4. Distillation (8 Torr, 588C) gave an impure
product; the combined distillates (5.12 g) were re-dissolved
in ether (20 ml) and dried with MgSO4 (1 week). Distillation
gave 2.40 g (yield of 37%) of a clear, colorless liquid.
1H NMR spectrum (90 MHz, CDCl3): d ˆ 2±2.7 ppm, m,
with a sharp spike at 2.45 ppm, 3.0 H, C(2)H2 ‡ OH; ˆ3.5±
4.5 ppm, m, 4.0 H, C(1)H2 ‡ C(3)H2. 19F NMR spectrum
(84.7 MHz, CDCl3): AB4 spectrum:jA ˆ 86.2 ppm, nine
lines, 1.0 F. jB ˆ 68.8 ppm, skewed d-m, 4.0 F,
JAB ˆ 147.2 Hz.
‡
GC±MS., Rt ˆ 5.06 min: 250, 248, m , 5.6, 5.2%; 169,
‡
‡
‡
‡
(m Br) , 13.7%; 127, SF5 , 5.4%; 122, 120, C3H5Br ,
‡
11.4, 11.2%; 95, 93, CH2Br , 5.1, 7.7%; 89, SF3 , 20.6%;
‡
‡
‡
61, (SCH2CH2 ‡ H) , 30.3%; 41, C3H5 , 100%; 39, C3H3 ,
30.5%. Anal. calcd. for C3H6BrF5S: C, 14.47; H, 2.43; Br,
32.08. Found: C, 14.63; H, 2.38; Br, 31.86%.
3.10. Ethyl a-bromo-b-chloro-b0-SF5-isobutyrate (3)
A 75 ml steel bomb tube was charged with 4.29 g
(28.9 mmol) of ethyl a-chloromethyl acrylate and 6.29 g
(30.4 mmol) of SF5Br. The container was maintained at
room temperature for 3 weeks. The contents were poured
into a 50 ml ¯ask and distilled at 1 Torr. Three fractions
were obtained: room temperature to 57.58C (2.23 g), from
57.58C to 59.58C and the third fraction was obtained by
Infrared spectrum (neat sample, KBr): 3688, vw; 3647, w;
3368, s,br (OH); 2967, w-m,br; 2897, w-m; 1630, vw, br;

R. Winter, G.L. Gard / Journal of Fluorine Chemistry 102 (2000) 79±87
85
‡
lowering the pressure to 40 m, 0.42 g. A yellow, viscous
residue remained in the ¯ask. All three fractions were of
GC±MS, Rt ˆ 7.56 min: 231, 233, (m OC2H5) , 2.1,
‡
7.6%; 229, 231, (m F±C2H5 ‡ H) , 6.5, 7.6% (mass 231
1
identical composition according to H NMR spectroscopy.
is counted to contribute to two fragmentation pathways; its
intensity should be ꢁ1/3 of mass 229 ‡ ꢁ3 times mass 233,
both containing chlorine; this is roughly found); 149, 151,
Yield, 6.97 g, 68%.1H NMR spectrum (500 MHz, CDCl3):
Ethyl group: dCH ˆ 1.34 ppm, t, 3., J ˆ 7.13 Æ 0.1 Hz;
3
‡
‡
(m SF5) , 3.3, 1.1%; 127, SF5 , 3.4%; 123, 125,
dOCH ˆ AB-system: dA ˆ 4.373, d-q; dB ˆ 4.322 ppm, d-
2
‡ ‡
q, JAB ˆ 11.0 Hz, JACH ˆ JBCH ˆ 7.14 Æ 0.1 Hz, 2.0 H
C3HClFS , 11.0, 3.3%; 120, 122, (m SF5±C2H5) , 4.0,
1.6%; 89, SF3 , 13.9%; 41, C3H5 , 55.7%; 39, C3H3 , 21.2%;
3
3
‡
‡
‡
(interpreted as quartet splitting of each line of the AB-
system); CH2Cl-group: AB-type system, dA ˆ 4.258 ppm,
d, dB ˆ 4.154 ppm, d, JAB ˆ 13.38 Hz, together 2.1 H;
SF5CH2: AB-type system: dA ˆ 4.578, d-p, 0.9 H; dB ˆ
4.445, d-p, 1.0 H, JAB ˆ 14.06 Hz, JBSF F ˆ JASF F Hz. 19F
‡
29, C2H5 , 100%.
4
4
NMR spectrum (84.7 MHz, CDCl3): AB4 spectrum:
jA ˆ 81.6 ppm, nine lines, 1.0 F; jB ˆ 68.0 ppm, skewed
d-m, 4.0 F, JAB ˆ 147.5 Hz. Infrared spectrum (neat sample,
KBr): 3042, vw; 2988, w; 2944,vw; 2912,vw; 2877, vw;
1746, s; 1467, vw; 1440, w; 1415, w; 1400,vw; 1371, w;
1316, s-m; 1267, m; 1255, m-w; 1229, m-s; 1216, m-s;
1145, w-vw; 1097,vw; 1065, m-s; 1012, w; 955, w-vw; 894,
m-s; 881, m-s; 835, vs; 799, w-vw; 751, vw; 666, vw; 639,
w-vw; 603, w-vw; 568, m; 554, m; 499, vw. GC±MS,
4. Ethyl n-heptacrylate (new procedure)
A chilled solution of 38.0 g of diethyl n-heptylmalonate
in 100 ml of absolute alcohol was treated with cold alco-
holic KOH (8.23 g KOH in 100 ml of alcohol) while being
stirred in an ice bath. The ice bath was removed after 30 min
and stirring was maintained overnight. After distilling away
most of the solvent, concentrated HBr was added to free the
acid, and the oily product was extracted with ether (1 Â 50
and 3 Â 20 ml), from which was obtained the crude mono-
ethyl ester of n-heptylmalonic acid (35.7 g).
The crude halfester was cooled in an ice bath, and
diethylamine (11.5 g) was added with stirring in ꢁ10 min
followed by 15 ml of formalin; a syrup was obtained.
Upon warming to room temperature bubbling and the
formation of an oily layer was soon observed. After
48 h, although there was still slight gas evolution, 100 ml
of 10:1 HBr was added; the upper layer separated and
washed twice with water (100, 25 ml) to give 27 g of a
pale yellow oil. Fractional distillation in the dynamic
vacuum gave a foreshot (20±658C), a main fraction
(65±708C), and a higher boiling cut (<808C). Of these,
the foreshot and main fraction were of identical composition
and combined Ð 22.2 g (yield was 76%) The product was a
clear, colorless, oily liquid. b.p. lit.: 65±698C/0.5 Torr
[9,10].
‡
Rt ˆ 9.56 min: 246, 248, (m C2H5OOC±Cl) , 3.9,
‡
3.8%; 154, 156, 158, C3H3ClBr , 16.6, 21.6, 5.2 %; 140
‡
‡
‡
SF5CH , 7.0%; 127, SF5 , 3.6%; 119, 121, C3H3Br , 11.4,
‡
‡
11.1%; 89, SF3 , 10.5%; 83, COOC2H5 , 3.9%; 75.0, 77.1,
‡
‡
C3H4Cl , 19.0, 6.4%; 39, C3H3 , 35%. Anal. calcd. for
C6H9BrClF5O2S: C, 20.77; H, 2.55; Br, 22.47; Cl, 9.97.
Found: C, 20.45; H, 2.55; Br, 22.39; Cl, 9.99%.
3.11. Ethyl b-chloro-b0-SF5-isobutyrate (10)
To a solution of 21.60 g of (3) (60.8 mmol) in 50 ml of
ether (250 ml round-bottom ¯ask in a water bath), was
added with stirring 19.7 g of tri-(n-butyl)tin hydride
(66.7 mmol) in 30 ml of ether over a 8 min period. A slight
turbidity appeared after 20 min, and the mixture was stored
at ambient temperature overnight. The supernatant ether
solution is decanted and the ether distilled away; the
remaining material was distilled and gave the main fraction
boiling at 77±808C/4±5 mm Hg, (11.31 g, yield was 67.3%).
1H NMR spectrum (500 MHz, CDCl3): d1(CH3) ˆ
1.31 ppm, t, J ˆ 7.04 Hz, d2(CH) ˆ 3.57 ppm, d-d-t;
Jd1 ˆ 5.05, Jd2 ˆ 7.38 Hz; Jt ˆ 5.08 Hz, d3(SF5CHH) ˆ
3.95 (center) ppm, m, d4(SF5CHH ‡ OCH2) ˆ 3.40
(center) ppm, m; d5(CH2Cl) ˆ 3.82 ppm, d, J ˆ 5.08 Hz.
1H NMR spectrum (CDCl3, 90 MHz): d1 ˆ 0.88 ppm,
very br., 3.0 H, CH3 in n-heptyl, d2 ˆ 1.2±1.7 ppm, m,
(CH2)5 in n-heptyl and CH3 in C2H5O, 13.5 H, d3 ˆ 2.34
ppm, asymm., br. t, a-CH2, 2.0 H, d4 ˆ 4.25 ppm, quartet,
J ˆ 7.26 Hz, OCH2CH3. d5 ˆ 5.59 ppm, s, 1.0 H,
H(bE) ˆ H cis to n-heptyl side chain, d6 ˆ 6.21 ppm, s,
1.0 H, H(bZ) ˆ H cis to ester grouping [15]. Infrared
spectrum (neat, NaCl): 3423, vw; 3104, vw; 2982, m,sh;
2958, s; 2929, s-vs; 2858, s; 1886, vw; 1758, m, sh; 1721, vs;
1632, m (nC=C); 1466, m; 1446, w-m, sh; 1409, w; 1369, m;
1329, m; 1302, m; 1280, m; 1256, m; 1240, m, sh; 1183, s;
1152, s; 1113, m-w; 1097, m; 1031, m; 941, m; 862, w; 818,
m; 782, vw; 725, w; 685, w.GC±MS, Rt ˆ 10.40 min: 198,
Integration: d1 (3.0), d2 (0.90), d3 (1.1), d4 (3.0), d5 (2.0). 19
F
NMR spectrum (84.7 MHz, CDCl3): AB4 spectrum:-
jA ˆ 84.5 ppm, nine lines, 1.0 F, jB ˆ 67.0 ppm, skewed
d-m, 4.0 F, JAB ˆ 147.8 Hz. Infrared spectrum (neat sample,
KBr): 3034, vw; 2988, w; 2946, vw; 2913, vw; 2879, vvw;
1742, s; 1469, w-vw; 1447, w; 1421, w-vw; 1382, w; 1336,
w; 1323, w; 1299, w; 1276, w-m; 1239, m; 1199, m-s; 1166,
m; 1114, vw; 1098, w; 1043, m; 1016, w; 956, vw; 872,
m-s,sh; 841, vs; 826, vs; 791, m, sh; 698, vvw; 683, vvw;
636, w; 623, w-vw; 599, w-m; 580, w.
‡
‡
1.3%, m ; 153, 13%, (m C2H5O) ; 115, 82%,
‡
(m C6H13 ‡ 2H) ; 102, 85% (?); 99, 19%,
‡
‡
‡
(m C7H15) ; 73, 31%, COOC2H5 ; 29, 100%, C2H5 .
Anal. calcd. for C12H22O2: C, 72.68; H, 11.18. Found: C,
72.57; H, 11.18%.

86
R. Winter, G.L. Gard / Journal of Fluorine Chemistry 102 (2000) 79±87
4.1. Ethyl 2-bromo-2-(pentafluorothiomethyl)pelargonate (4)
freezing ( 1968C) and evacuating, SF5Cl (0.50 g,
3.1 mmol) was added by condensation. The Carius tube
was allowed to warm up to such a point when the contents
were just melted, then shaken and re-frozen ( 1968C) and
then allowed to warm up slowly in a pre-cooled Dewar
container (also at liquid-nitrogen temperature). After 24 h, a
pale yellow liquor was obtained which was diluted with
methylene chloride to 100 ml in a volumetric ¯ask. GC±MS
revealed that there was practically pure ClCH(COOC2H5)2,
in all aspects similar to a commercial sample. A feeble
signal for diethyl malonate was also observed. Chlormalo-
nic ester was quanti®ed with the aid of a calibration curve
and indicated a (gas-chromatographic) yield of 97%. A
similar run was used to detect ¯uorine-containing products,
where the reaction mixture was used for 19F NMR spectro-
scopy without dilution by CH2Cl2, observed was a singlet at
ꢁ77 ppm (SF4), a pentet at 64 ppm (jA in SF5Cl, the scan
was not extended beyond of 100 ppm so that jB was not
recorded) and a barely resolved signal at 218.5 ppm, a
quartet of a triplet, Jq ˆ 46.3, Jt ˆ 25.4 Hz, assigned to
ethyl ¯uoride.
Into a 75 ml steel bomb, ethyl n-heptacrylate (8.60 g,
43.4. mmol) and SF5Br, (9.5 g, 45.9 mmol) were added and
the temperature was maintaied at room temperature over-
night. After cooling the bomb to 08C, a sample was with-
drawn; while infrared spectroscopy showed the absence of
an ole®nic band, GC±MS indicated a small amount of
remaining acrylic ester. The bomb tube was sealed again,
evacuated ( 1968C), and then an additional amount of
SF5Br (2.3 g ꢁ 11 mmol) was added; the vessel heated
overnight at 50±558C. The product was pipetted from the
reaction vessel (16.94 g, and twice rinsed with a few ml of
CHCl3) and distilled (dynamic vacuum): ®rst fraction,
1.23 g, 85.5±87.58C, 27±22 m, oily, colorless liquid; second
fraction, 13.69 g, 87.5±958C, 22±20 m, oily, colorless liquid.
A small amount of waxy solid remained in the ¯ask; both
fractions had identical infrared spectra and were combined.
Yield ˆ 14.92 g, 85%.
1H NMR spectrum (500 MHz, CDCl3): dCH ˆ 1.33 ppm,
3
t, (together with (CH2)5); Jmeas ˆ 7.73 Hz, (CH3 of ethyl),
dOCH ˆ AB-system: dA ˆ 4.285; dB ˆ 4.328 ppm, JAB
ꢁ
Literature: j ˆ 216.9 ppm, q-t, JCH
ˆ 47.6 Hz,
ꢀF†
2
2
10.6 Hz, JACH ˆ JBCH ˆ 7.03 Hz, 1.9 H. (interpreted as
JCH
ˆ 25.7 Hz [16,17].1
ꢀF†
3
3
3
quartet splitting of each line of the AB-system). dCH
ˆ
ˆ
3
0.90 ppm, t, J ˆ 6.84 Hz, 3.1 H. (CH3 of n-heptyl) d
ꢀCH2†
5
1.2±1.8 ppm, broad m, 13.3 H (superimposed with CH3 of
Acknowledgements
ethyl group), dCH ꢀCH † CH ˆ AB-system: dA ˆ 2.058 ppm,
2
2
3
5
0
0
d-d-d; JAB ˆ 14.9 Hz, JAH ˆ 4.1 Hz, JAH ꢁ 12 Hz, 0.9 H,
We are grateful to the National Science Foundation
(CHE-9632815) and the Petroleum Research Foundation
(ACS-PRF 31099-AC1) for support of this work. We also
are grateful to Jane Kelly for recording the 500 MHz NMR
spectra.
0
0
dB ˆ 2.359 ppm, d-d-d, JBH ˆ 3.7 Hz, JBH ꢁ 12 Hz, 0.9
H, (H0,H00, neighboring CH2-group). SF5CH2: AB-type: dA ˆ
4.187 ppm, d-p, JAB ˆ 14.1 Hz, 1.1 H, dB ˆ 4.634 ppm,
d-p, 0.9 H. JASF F ˆ 7.23 Hz; JBSF F ˆ 8.01 Hz 19F NMR
4
4
spectrum (84.7 MHz, CDCl3): AB4 spectrum: jA ˆ
82.80 ppm, nine lines, 1.00 F, jB ˆ 67.90 ppm, skewed
d-m, JAB ˆ 147.7 Hz, 3.94 F. Infrared spectrum (neat sam-
ple, KBr): 3040, vw; 2981, m, sh; 2960, m-s; 2932, s; 2874,
m, sh; 2859, m-s; 1749, s-vs; 1467, m; 1460, m,sh; 1449, m-
w; 1419, m-w; 1392, vw; 1378, w-vw,sh; 1370, m-w; 1325,
w,sh; 1306, m; 1283, m; 1265, m; 1244, m; 1217, s; 1160, w-
m; 1115, m; 1097, w-m; 1071, m; 1032, m; 974, vw; 925,
vw; 890, s, sh; 881, s; 845, vs; 832, vs; 810, vw, sh; 761, vw;
741, vw; 726, w; 704, vw; 667, vw; 643, w-m; 603, w; 588,
w; 568, m-s; 553, m. GC±MS, Rt ˆ 12.93 min.: 404, 406,
References
[1] Y.U. Studnev, V.P. Stolyarov, G.A. Prigorelov, A.V. Fokin, Izv.Akad.
Nauk, SSSR, Ser. Khim. 1 (1989) 197.
[2] R. Winter, G.L. Gard, J. Fluorine Chem. 66 (1994) 109.
[3] H.C. Brown, M. Choi, S. Narasimshan, J. Org. Chem. 47 (1982)
3153.
[4] H.L. Roberts, N.H. Ray, British Patent, 906 448, 1960.
[5] E. Ziegler, H. Sterk, Monatshefte Chem. 98 (1967) 1104.
[6] J.-P. Pete, Bull. Soc. Chim. Fr. (1967) 357.
[7] H.L. Cross, G. Cushing, H.L. Roberts, Spectrochim. Acta 17 (1961)
344.
‡
‡
m , 0.04, 0.05%; 231, 233, (m SF5±C2H5O±H) , 1.6,
‡
1.7%; 179, 181, (m C7H15±SF5 ‡ H) , 19.8, 19.1%; 127,
‡
‡
‡
‡
SF5 ; 2.5%; 123, C9H15, 26.8%; 95, SC5H3 , 13.6%; 89,
SF3 , 9.6%; 69, (C4H4O ‡ H) , 51.5%; 68, C4H4O ,
[8] C. Mannich, K. Ritsert, Ber. 57B (1924) 1116.
[9] B. Kirschleger, R. Queignec, Synthesis, 1986 926.
Â
[10] J. Villieras, M. Rambaud, Synthesis, 1984 406.
‡
‡
‡
‡
10.2%; 67, C4H3O , 28.7%; 55, C4H7 , 54.4%; 45,
‡
‡
‡
Â
[11] J. Villieras, M. Rambaud, Synthesis, 1982 924.
C2H5O , 6%; 43, C3H7 , 63.8%; 41, C3H5 , 82.7%; 29,
‡
[12] S.A. Glickman, A.C. Cope, J. Am. Chem. Soc. 67 (1945) 1096.
[13] K. Thomas, G. Weitzel, P. Neumann, Z. Physiol. Chemie 282 (1947)
194.
C2H5 , 100%. Anal. calcd. for C12H22BrF5O2S: C, 35.56; H,
5.47; F, 23.4. Found: C, 36.68; H, 5.51; F, 22.7%.
4.2. Ethyl b-,b-diethoxyacrylate and SF5Cl (13)
1 The chemical shift is cited with respect to perfluorocyclobutene
(j ˆ ‡76.95 ppm). The conversion formula jCCl F ꢁ jC
‡ 139.9
C4F8
3
A 75 ml Carius tube was charged with 0.50 g (2.7 mmol)
of ethyl b-,b-diethoxyacrylate and 17.2 g Freon-113; after
[17] was used. The negative sign applies because of a change of
convention.

R. Winter, G.L. Gard / Journal of Fluorine Chemistry 102 (2000) 79±87
87
[14] J.v. Braun, E. Anton, W. May, Ber. 70 (1937) 1250.
[15] U.E. Matter, C. Pasqual, E. Pretsch, A. Pross, W. Simon, S. Sternhell,
Tetrahed. 25 (1969) 691.
[17] J.W. Emsley, F. Feeney, L.H. Sutcliffe (Eds), High Resolution
Nuclear Magnetic Spectroscopy, Vol. 2, 1st ed., Pergamon,
Oxford, UK, 1966, footnotes, pp. 885±886 (referring to external
standards).
[16] D.D. Ellemann, L.C. Brown, D. Williams, J. Mol. Spectroscopy 7
(1961) 307.