Synthesis of 3-perfluoroalkyl-propyl esters of L-(+)-tartaric acid

Article abstract of DOI:10.1016/S0022-1139(99)00061-5

A convenient and effective method for the preparation of perfluoroalkyl-propanols (F-(CF₂)_n-(CH₂)₃-OH, n = 6,8,10) via boric acid esters is described. The radical addition of F-alkyl iodides to the C=C double bonds of triallyl borate is followed by the reduction step using tributylstannane hydride under one-pot conditions. Finally, the mild aqueous deprotection of the alcoholic function completes the reaction with an overall yield of 75-79%. The fluorophilicity (f) values of these and some other fluoroalcohols, which describe their phase preference, were determined by gas chromatography. F-alkyl-propanols are useful synthetic precursors of fluorinated esters of L-tartaric acid - potential chelating agents in fluorous biphase transformations.

Full text of DOI:10.1016/S0022-1139(99)00061-5

Journal of Fluorine Chemistry 98 (1999) 83±87
Synthesis of 3-per¯uoroalkyl-propyl esters of L-(‡)-tartaric acid
a,*
a
Zoltan Szlavik , Gabor Tarkanyi , Gyorgy Tarczay , Agnes Gomory , Jozsef Rabai
c
b
d
Â
Department of Organic Chemistry, Eotvos University, P.O. Box 32, H-1518, Budapest 112, Hungary
Â
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È
È È
a
È
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b
È
È
Department of General and Inorganic Chemistry, Eotvos University, P.O. Box 32, H-1518, Budapest 112, Hungary
cChemical Works of Gedeon Richter, Spectroscopic Research Division, Budapest, Hungary
dInstitute of Chemistry, Chemical Research Center, Hungarian Academy of Sciences, P.O. Box 17, H-1525, Budapest, Hungary
Received 24 August 1998; accepted 16 February 1999
Abstract
A convenient and effective method for the preparation of per¯uoroalkyl-propanols (F±(CF2)n±(CH2)3±OH, n ˆ 6,8,10) via boric acid
esters is described. The radical addition of F-alkyl iodides to the C=C double bonds of triallyl borate is followed by the reduction step using
tributylstannane hydride under one-pot conditions. Finally, the mild aqueous deprotection of the alcoholic function completes the reaction
with an overall yield of 75±79%. The ¯uorophilicity (f) values of these and some other ¯uoroalcohols, which describe their phase
preference, were determined by gas chromatography. F-alkyl-propanols are useful synthetic precursors of ¯uorinated esters of L-tartaric
acidÐpotential chelating agents in ¯uorous biphase transformations. # 1999 Elsevier Science S.A. All rights reserved.
Keywords: Per¯uoroalkyl-propanols preparation; Reduction; Fluorinated esters of L-tartaric acid; Preparation; Esteri®cation; Fluorophilicity; Gas
chromatography
1. Introduction
ments of phase behaviour, thus aiding design of novel
¯uorophilic compounds. It has been a signi®cant challenge
for synthesis chemists over the past decade to synthesize
optically pure products using chiral catalysts. Integrating the
known enantioselective transformation methods with the
FBS approach is a logical extension of both approaches.
The ®rst application of enantioselective reactions in the
unique solvation environment provided by (per)¯uorocar-
bons was recently reported by Pozzi et al. [13]. They
synthesized two optically active per¯uoroalkylated (salen)-
MnIII complexes (Jacobsen±Katsuki catalysts) and suc-
cessfully used them in chiral ¯uorous biphase epoxidation
of alkenes (up to ee: 92%). In the present work, we describe
a simple and ef®cient synthesis of per¯uoroalkyl-propyl
esters of L-tartaric acid as ¯uorinated analogues of alkyl
tartrates which are widely used in enantioselective reactions
as chelating ligands of transition metals [14].
Many preparations of the synthetic precursor F-alkyl-
propanols are known in the literature [15±17], but we aimed
at developing a more convenient and successful synthetic
pathway. The ®rst, a radical addition step of F-alkyl iodides
(RFI) to the C=C double bond of allyl alcohol produces
higher conversions under more controllable conditions, if
the hydroxyl group is protected [15,18±20]. The second, a
reduction step can be suitably carried out with tributylstan-
The recent discovery of ¯uorous biphase systems (FBS)
Â
Â
by Horvath and Rabai has provided novel methods for
catalyst and reagent immobilization coupled with product
separation [1]. In this pioneer work it was demonstrated that
a phosphine ligand with suitable ¯uorinated `ponytails'
[P(CH2CH2C6F13)3] can be applied in hydroformylation
reactions in a biphasic mixture of toluene and a ¯uorocar-
bon-type solvent, and simple phase separation suf®ced to
provide the products and the ¯uorous catalyst, which could
be easily recycled. The bene®ts of application of this
approach in homogeneous catalysis, ¯uorous synthesisÐ
in which organic molecules are systematically rendered
soluble in ¯uorocarbon solvents by the attachment of an
adequate per¯uorinated segmentÐand liquid-phase combi-
natorial synthesis are appearing [2±6]. However, a more
extensive application of this novel phase separation and
immobilization concept requires convenient and effective
access to designed ¯uorous catalysts, reagents, ligands and
labels. Fluorous partition coef®cients [6±10] and ¯uorophi-
licity (f) values [11,12] have become preferred measure-
*Corresponding author. Tel.: +36-1-209-0555 ext. 1416; fax: +36-1-
296-6832; e-mail: rabai@szerves.chem.elte.hu
0022-1139/99/$ ± see front matter # 1999 Elsevier Science S.A. All rights reserved.
PII: S 0 0 2 2 - 1 1 3 9 ( 9 9 ) 0 0 0 6 1 - 5

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Z. Szlavik et al. / Journal of Fluorine Chemistry 98 (1999) 83±87
84
Table 1
nane hydride in the presence of the radical initiator AIBN
[15], and, ®nally, the deprotection of the hydroxyl function
completes the procedure.
The fluorophilicity (f) values of F-alkyl-propanols (F±(CF2)n±(CH2)3±
OH) and some commercially available fluoroalcohols
F-alcohol
Fw
Fluorine
f
The trimethylene spacer unit in F-alkyl-propanols
inserted in-between the hydroxyl group and the per¯uori-
nated segment reduces the electron withdrawing effect and
ensures usual reactivity of the functional group [1,21].
These ¯uorinated propanols are novel examples indicating
that the experimental determination of ¯uorophilicity (f)
values is essential for the understanding of how different
constituents of a molecule affect its phase behaviour. It is
also hoped that the systematic collection of ¯uorophilicity
data could lead to the development of a structure±¯uoro-
philicity correlation model, which then would allow the
prediction of ¯uorophilicity values for the design of novel
¯uorous compounds.
content (%)
CF3±CH2±OH
100.0
168.0
364.1
378.1
464.1
478.2
587.2
57.0
67.8
67.8
65.3
69.6
67.6
69.0
1.77 Æ 0.16
1.01 Æ 0.08
0.10 Æ 0.03
0.23 Æ 0.05
1.02 Æ 0.03
0.59 Æ 0.04
1.42 Æ 0.20
(CF3)2CH±OH
F±(CF2)6±(CH2)2±OH
F±(CF2)6±(CH2)3±OH
F±(CF2)8±(CH2)2±OH
F±(CF2)8±(CH2)3±OH
F±(CF2)10±(CH2)3±OH
de®ned from the partition coef®cient (Pa) between two
particular solvents, per¯uoro(methylcyclohexane) and
toluene at 258C according to the following equation [11,12]:
fa ˆ ln Pa ꢁ ln ‰caꢀCF3C6F11†=caꢀCH3C6H5†Š:
According to this de®nition a molecule is `¯uorophilic' if its
f value is positive. The measurement of this parameter in the
case of a volatile ¯uorinated compound can be easily made
by gas chromatography. If the volumes of the two phases
and the sampled and injected volumes are the same, then the
integrated areas (Aa) determine the ¯uorophilicity value:
2. Results and discussion
The novel synthesis of per¯uoroalkyl-propanols is based
on a procedure described of Krahler using triallyl borate as
starting material [19,20]. The protection of the alcoholic
function via boric acid ester has two essential advantages
compared to other methods. First, the deprotection of the
product can be carried out under extremely mild conditions,
simply by introducing water into the system. On the
other hand, the radical addition of F-alkyl iodide to
triallyl borate in the presence of AIBN is so effective
(the complete conversion was checked by GC), that this
provides the opportunity of direct reduction without isola-
tion of the adduct formed. The preferred reagent for this
reaction is tributylstannane hydride because it also functions
under radical conditions and can be added directly to the
reaction mixture. The method requires oxygen-free, anhy-
drous conditions and precise control of the reaction tem-
perature. With this one-pot synthesis, an overall yield of 75±
79% can be obtained based on the initial per¯uoroalkyl
iodides:
fa ˆ ln ‰AaꢀCF3C6F11†=AaꢀCH3C6H5†Š:
The ¯uorophilicity (f) values of F-alkyl-propanols and
some commercially available ¯uoroalcohols were deter-
mined to compare their phase preference (Table 1). Tri-
¯uoroethanol, hexa¯uoroisopropyl alkohol and F-hexyl-
propanol have negative f values in spite of their relatively
high ¯uorine content, while the others with long per¯uor-
oalkyl chains are ¯uorophilic. The f values of F-alkyl-
alkanols increase with the size of the per¯uorinated seg-
ment, as expected [22]. In case of the alcohols with the same
size of per¯uoroalkyl groups, the trimethylene spacer results
in lower f values than the shorter ethylene unit.
The preparation of potential chiral ¯uorinated complex-
ing ligands derived from F-alkyl-propanols and L-tartaric
acid is summarized in the following equation:
ꢀCH2ˆCH CH2 O†3B ‡ 3RnFI
The final separation of the unreacted alcohols from the
products is worked out in all cases, because the recycling of
the relatively expensive starting materials is a basic require-
ment. The average yield of the esterification procedure is
80%. While F-hexyl-propyl tartrate can be readily dissolved
in organic solvents, such as diethyl ether, methanol and
chloroform, the solubility properties of the other two ana-
logues decrease drastically with the size of the F-alkyl unit.
These esters are only slightly soluble in perfluorocarbons,
AIBN
! ꢀRnF CH2 CHI CH2 O†3B
Bu3SnH=AIBN
!
ꢀRnF CH2 CH2 CH2 O†3B
Bu3SnI
H2O
! 3RnF CH2 CH2 CH2 OH ꢀn ˆ 6; 8; 10†
H3BO3
1
3
The ¯uorophilicity value (fa) of a compound `a' has been

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Z. Szlavik et al. / Journal of Fluorine Chemistry 98 (1999) 83±87
85
such as perfluoro(methylcyclohexane) and perfluoro(2-
butyltetrahydrofuran), but can be easily dissolved in par-
tially fluorinated alcohols like F-hexyl-ethanol or hexa-
fluoroisopropyl alcohol.
range (m/z) from 25 to 1500 was considered. Both, in the
case of per¯uoroalkyl-propanols and their tartrates appro-
priate molecular ions were detected; however, the latter ions
showed less intensity (ca. 1% of the base peak intensity).
HRMS measurements were performed similarly, except
using FAB technique for ionization of the tartrate samples.
Optical rotation was determined by a Polamat A (Zeiss)
polarimeter. The reaction steps of the one-pot synthesis of
F-alkyl-propanols were monitored by gas chromatography
(Hewlett±Packard 5890 Series II, Pona 50 m  0.2 mm Â
0.5 mm column, H2 carrier gas, FID). The ¯uorophilicity
values were also determined by GC in the following man-
ner: In a 2.00-ml volumetric ¯ask having conical bottom, the
given compounds (10 mg) were extracted in a 1.00±1.00 ml
mixture of pre-equilibrated per¯uoro(methylcyclohexane)
and toluene at 258C. After standing overnight at this tem-
perature, 0.5, 1 and 2 ml samples of the separated upper and
lower phases were injected onto the capillary column. Then,
volume ratios with best matching integrals for both phases
were used. Due care was practised so as not to disturb the
clean and transparent phases when sampled with a Hamilton
syringe. An average of 5±5 injections for each run of three
independent determinations resulted in the listed f values
(Table 1).
3. Conclusions
The foregoing description of one-pot preparation of F-
alkyl-propanols via boric acid esters is a convenient and
noticeably effective method. The gas chromatographic mea-
surement of the well-de®ned ¯uorophilicity values is a
simple technique to express the ¯uorocarbon phase prefer-
ence of volatile compounds. The collection of a vast amount
of ¯uorophilicity data is necessary to understand the strat-
egy of how to design systematically novel ¯uorous com-
pounds. The tartaric acid esters derived from F-alkyl-
propanols are practically insoluble in per¯uorocarbons at
room temperature presumably due to the strong ordering
capacity of the hydroxyl functions forming hydrogen bonds.
This effect is eliminated if these molecules chelate transi-
tion metals, thus hopefully increasing the solubility in
¯uorocarbon media and opening perspectives in the appli-
cation of these ligands in chiral ¯uorous biphase transfor-
mations.
4.1. Preparation of perfluoroalkyl-propanols
4. Experimental details
4.1.1. 4,4,5,5,6,6,7,7,8,8,9,9,9-Tridecafluoro-nonan-1-ol
(1)
Triallyl borate was prepared from freshly distilled allyl
alcohol (Merck) [20]. The following chemicals were used
for the one-pot preparation of F-alkyl-propanols and the
esteri®cation procedures: per¯uoroalkyl iodides (Fluoro-
chem), AIBN (Fluka), tributylstannane hydride (Aldrich),
L-(‡)-tartaric acid and p-toluenesulfonic acid monohydrate
(both Reanal, Hungary). For partition coef®cient determi-
nations F-octyl-ethanol (Fluka), F-hexyl-ethanol (PCR),
tri¯uoroethanol and hexa¯uoroisopropyl alcohol (both
Aldrich) reagent grade chemicals were used as received,
while per¯uoro(methylcyclohexane) (Fluorochem, 90%)
was puri®ed by re¯uxing with oleum (40% free SO3, 6 h)
followed by distillation, washing with water, drying
(MgSO4) and distilling to afford 98% purity by GC. Deut-
erated solvents and internal references for NMR analysis
were originated from Merck. Melting points were deter-
mined on a Boetius micromelting point apparatus and are
uncorrected. Sonications were performed using a Realsonic
(RS-I6, 50/100 W) laboratory ultrasound cleaner. The struc-
tures of all products were proved by FT-IR (Bruker IFS 55),
1H-, 13C- and 19F-NMR spectroscopy (Varian INOVA-300,
In a pre-dried, nitrogen purged reaction ¯ask per¯uor-
ohexyl iodide (30.0 g, 67.3 mmol), triallyl borate (4.08 g,
22.4 mmol) and AIBN (0.10 g, 0.61 mmol) were mixed at
room temperature. Continuous stirring and by-pass nitrogen
¯ow was applied during the entire reaction. The temperature
was raised to 708C over 30 min and held at this temperature
for 1 h. An additional amount of AIBN (0.1 g) was added to
the mixture, which was then slowly heated to 808C. After
3 h, a small sample was hydrolyzed and the ether extract was
analyzed by GC (100% conversion). The reaction tempera-
ture was decreased to 70±738C and AIBN (0.1 g) was added
to the mixture. Tributylstannane hydride (20.2 g,
69.4 mmol) was added dropwise over 2 h. Additional AIBN
(0.05 g) was introduced and the temperature was maintained
for 1 h, then heated to 808C for 30 min to complete the
reduction (checked by GC). Finally, distilled water (50 ml)
was added and the reaction mixture was stirred intensively
for 20 min at the same temperature. The mixture was cooled
to room temperature and the organic components were
extracted with diethyl ether (3 Â 50 ml). The ether phase
was washed with water, separated, and dried over Na2SO4,
and the solvent removed by rotary evaporation. The residue
was distilled under reduced pressure (16 mmHg). The
main fraction was collected over a temperature range
of 90±1008C (93.3% purity by GC), the second one at
100±1308C (83.7% purity). Repeated distillation using a
Vigreaux column (b.p. 918C/16 mmHg, in accordance with
1
300 MHz for H) using TMS and CFCl3 as internal stan-
dards. Only 13C-NMR spectra of non¯uorinated carbons
were considered. Mass spectra were determined on a VG
ZAB2-SEQ tandem mass spectrometer using electron
impact (70 eV) for ionization and direct probe for sample
introduction at a source temperature of 180 to 2508C. Mass

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Z. Szlavik et al. / Journal of Fluorine Chemistry 98 (1999) 83±87
86
the literature [23]: 86±888C/12 mmHg) gave 19.0 g of
product 1 (74.7%, 97.1% purity by GC). NMR (CD3OD)
d: 1H: 1.76±1.86 m (2H) [H2-2]; 2.15±2.37 m (2H) [H2-3];
37; 495, 14, M-83; 69, 56,, CF3; 47, 48, OCF; 31, 100, CF.
‡
HRMS (m/z) calculated for C13H7F21O, M ˆ 578.0162,
‡
found M ˆ 578.0154; calculated. for C13H5F20O, (M-
3
‡
‡
3.64 t JHH ˆ 6.0 Hz (2H) [H2-1]; 13C: 24.6 (3JCF < 4 Hz)
H2F) ˆ 557.0021, found (M-H2F) ˆ 557.0026; calcu-
(C-2); 28.9 t (2JCF ˆ 22 Hz) (C-3); 61.7 (C-1); 19F: 81.3 m
(3F) [CF3]; CF2 resonances are 114.1 m (2F), 121.7 m
(2F), 122.7 m (2F), 123.3 m (2F), 126.1 m (2F). FT-IR
(CCl4) ꢀ (cm 1): 3640.3 (OH), 2958.9 (CHas), 2882.7
(CHs), 1240.8, 1207.8 (CF). MS (m/z, I%, M-X): 378,
5.3, M; 377, 21, M-1; 341, 12, M-37; 295, 8.3, M-83;
69, 26, CF3; 47, 51, OCF; 31, 100, CF. HRMS (m/z)
lated for C13H5F20, (M-OH2F) ˆ 541.0072, found (M±
‡
‡
OH2F) ˆ 541.0081; calculated for C13H6F19O, (M±
‡
‡
HF2) ˆ 539.0115, found (M±HF2) ˆ 539.0132.
4.2. Esterification procedures
4.2.1. 2R,3R-dihydroxy-succinic acid bis-
(4,4,5,5,6,6,7,7,8,8,9,9,9-tridecafluoro-nonyl)
ester (4)
‡
calculated for C9H7F13O, M ˆ 378.0289, found
‡
M ˆ 378.0298.
In a reaction ¯ask ®tted with a Dean±Stark trap for the
removal of water during the reaction a mixture of 1 (5.00 g,
13.2 mmol), L-tartaric acid (0.795 g, 5.30 mmol) and p-
toluenesulfonic acid monohydrate (0.190 g, 1.00 mmol)
in toluene (50 ml) was re¯uxed at an oil bath of 1458C
for 24 h. Toluene was removed and the residue extracted
with ether and washed twice with distilled water. The ether
layer was separated, dried over Na2SO4 and the solvent
removed. Unreacted 1 was recovered using a short-path
distillation apparatus (0.512 g, 92.5% purity by GC). The
distillation residue was recrystallized from toluene (50 ml),
resulting in 3.72 g product (80.7%), m.p. 78±808C,
4.1.2. 4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-
Heptadecafluoro-undecan-1-ol (2)
In a nitrogen-purged ¯ask per¯uorooctyl iodide (20.0 g,
36.6 mmol), triallyl borate (2.22 g, 12.2 mmol) and AIBN
(0.05 g, 0.30 mmol) were dissolved in isooctane (25 ml) at
room temperature. The addition and dehalogenation proce-
dures using tributylstannane hydride (10.2 g, 35.0 mmol)
were carried out as above (temperature programme, initiator
addition). After hydrolysis with distilled water (50 ml), the
crude product precipitated from the cold isooctane phase. It
was ®ltered, dried and recrystallized twice from isooctane.
Yield: 13.5 g (77.0%, 98.1% purity by GC), m.p. 42±438C,
(in accordance with the literature [24]: 428C). NMR
25
[a]546 ˆ 12.4 (c ˆ 2.50 g/100 ml, F-hexyl-ethanol).
NMR (CD3OD) d: 1H: 1.95±2.08 m (4H) [H2-2]; 2.21±
2.43 m (4H) [H2-3]; 4.24±4.38 m (4H) [Hx,y-1]; 4.59 s
(2H) [H±(CH±O)]; 13C: 21.3 t (3JCF <4 Hz) (C-2); 28.8 t
(2JCF ˆ 22 Hz) (C-3); 65.2 (C-1), 74.1 (C±(CH±O)), 172.9
(C=O); 19F: 81.3 m (3F) [CF3]; CF2 resonances are
114.2 m (2F), 121.7 m (2F), 122.7 m (2F), 123.2
m (2F), 126.1 m (2F). FT-IR (KBr) ꢀ (cm 1): 3540.4
(OH), 2979.3 (CH), 1741.8 (C=O); 1235.8, 1192.6 (CF).
HRMS (FAB, m/z) calculated for C22H17F26O6,
1
(CD3OD) d: H: 1.76±1.86 m (2H) [H2-2]; 2.15±2.37 m
3
(2H) [H2-3]; 3.64 t JHH ˆ 6.0 Hz (2H) [H2-1]; 13C: 24.6
(3JCF < 4 Hz) (C-2); 28.9 t (2JCF ˆ 22 Hz) (C-3); 61.7 (C-
1); 19F: 81.3 m (3F) [CF3]; CF2 resonances are 114.2 m
(2F), 121.7 m (6F), 122.5 m (2F), 123.3 m (2F),
126.1 m (2F). FT-IR (CCl4) ꢀ (cm 1): 3640.3 (OH),
2958.7 (CHas), 2882.8 (CHs), 1242.2, 1215.1 (CF). MS
(m/z, I%, M-X): 478, 3.9, M; 477, 3.7, M-1; 441, 9.3, M-
37; 395, 6.3, M-83; 69, 24, CF3; 47, 22, OCF; 31, 100, CF.
‡
‡
(M ‡ H) ˆ 871.0610, found (M ‡ H) ˆ 871.0591.
‡
HRMS (m/z) calculated for C11H7F17O, M ˆ 478.0225,
‡
found M ˆ 478.0224.
4.2.2. 2R,3R-dihydroxy-succinic acid bis-
(4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-
heptadecafluoro-undecyl) ester (5)
4.1.3. 4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,13-
Heneicosafluoro-tridecan-1-ol (3)
Initial quantities were the following: compound 2 (3.35 g,
7.00 mmol), L-tartaric acid (0.420 g, 2.80 mmol) and p-
toluenesulfonic acid monohydrate (0.133 g, 0.70 mmol)
in toluene (50 ml). The experimental conditions and the
work-up procedure were the same as in the previous case.
The amount of 2 recovered was 0.482 g (GC pure). The
product was recrystallized from toluene. Yield: 2.36 g
The following quantities of reagents were used: per¯uor-
odecyl iodide (10.0 g, 15.5 mmol), triallyl borate (0.941 g,
5.17 mmol) and AIBN (0.03 g, 0.18 mmol) in isooctane
(25 ml). Tributylstannane hydride (4.95 g, 17.0 mmol)
was used for the reduction. The reaction conditions and
work-up procedure were as in the case of compound 2.
Yield: 7.10 g (79.2%, 98.0% purity by GC), m.p. 86±898C.
NMR (CD3OD) ꢁ: 1H: 1.76±1.86 m (2H) [H2-2]; 2.15±2.37
m (2H) [H2-3]; 3.63 t 3JHH ˆ 6.0 Hz (2H) [H2-1]; 13C: 24.6
(3JCF <4 Hz) (C-2); 28.9 t (2JCF ˆ 22 Hz) (C-3); 61.6 (C-1);
19F: 81.2 m (3F) [CF3]; CF2 resonances are 114.1 m
(2F), 121.5 m (10F), 122.5 m (2F), 123.3 m (2F),
126.0 m (2F). FT-IR (CCl4) ꢀ (cm 1): 3639.8 (OH),
2958.5 (CHas), 2872.1 (CHs), 1242.4, 1217.4 (CF). MS
(m/z, I%, M-X): 578, 2.7, M; 577, 7.3, M-1; 541, 25, M-
25
(78.7%), m.p. 109±1108C, [a]546 ˆ 10.9 (c ˆ 2.58 g/
100 ml, F-hexyl-ethanol). NMR ((CF3)2CDOD) d: 1H:
2.05±2.21 m (4H) [H2-2]; 2.21±2.38 m (4H) [H2-3];
4.33±4.47 m (4H) [Hx,y-1]; 4.54 s (2H) [H±(CH±O)];
13C: 21.6 t (3JCF <4 Hz) (C-2); 29.6 (2JCF ˆ 22 Hz) (C-
3); 68.5 (C-1), 74.2 (C±(CH±O)), 174.4 (C=O); 19F: 81.6
m (3F) [CF3]; CF2 resonances are 114.5 m (2F), 121.5 m
(2F), 121.7 m (4F), 122.6 m (2F), 123.4 m (2F),
126.3 m (2F). FT-IR (KBr) ꢀ (cm 1): 3540.6 (OH),

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Z. Szlavik et al. / Journal of Fluorine Chemistry 98 (1999) 83±87
87
2978.1 (CH), 1741.4 (C=O); 1237.5, 1204.8 (CF). HRMS
‡
References
(FAB, m/z) calculated for C26H17F34O6, (M ‡ H) ˆ
‡
 Â
[1] I.T. Horvath, J. Rabai, Science 266 (1994) 72.
[2] D.P. Curran, Angew. Chem., Int. Ed. Engl. 37 (1998) 1175.
[3] B. Cornils, Angew. Chem., Int. Ed. Engl. 36 (1997) 2057.
1071.0482, found (M ‡ H) ˆ 1071.0331.
4.2.3. 2R,3R-dihydroxy-succinic acid bis-
(4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13,13-
heneicosafluoro-tridecyl) ester (6)
[4] A. Studer, S. Hadida, R. Ferritto, S.Y. Kim, P. Jeger, P. Wipf, D.P.
Curran, Science 275 (1997) 823.
[5] A. Studer, D.P. Curran, Tetrahedron 53 (1997) 6681.
Â
[6] I.T. Horvath, Acc. Chem. Res. 31 (1998) 641.
Compound
3
(3.00 g, 5.19 mmol), L-tartaric acid
Â
[7] L. Sole-Violan, B. Devallez, M. Postel, J.G. Riess, New J. Chem. 17
(1993) 581.
(0.312 g, 2.08 mmol) and p-toluenesulfonic acid monohy-
drate (0.095 g, 0.50 mmol) in toluene (30 ml). The experi-
mental conditions were the same as described above. The
mixture was cooled to room temperature. The solidi®ed
mixture was ®ltered and sonicated in 50 ml of methanol for
10 min. The solid was ®ltered and the sonication procedure
was repeated with another 50 ml of methanol. The crude
product was ®ltered again and dried. From the combined
®ltrates, 0.211 g 3 was recovered (97.6% purity by GC). The
dry product was recrystallized from boiling toluene. Yield:
[8] D.P. Curran, M. Hoshino, J. Org. Chem. 61 (1996) 6480.
[9] L.J. Alvey, D. Rutherford, J.J.J. Juliette, J.A. Gladysz, J. Org. Chem.
63 (1998) 6302.
Â
[10] V. Herrera, P.J.F. de Rege, I.T. Horvath, T.L. Husebo, R.P. Hughes,
Inorg. Chem. Commun. 1 (1998) 197.
Â
Â
Â
Â
[11] J. Rabai, Z. Szlavik, G. Halasz, L.E. Kiss, A. Csampai, L. Varga,
15th International Symposium on Fluorine Chemistry, Vancouver,
Canada, August, 1997, Abstract, In(1) C-7.
Â
È
[12] L.E. Kiss, J. Rabai, L. Varga, I. Kovesdi, Synlett. (1998) 1243.
[13] G. Pozzi, F. Cinato, F. Montanari, S. Quici, J. Chem. Soc., Chem.
Commun. (1998) 877.
25
2.09 g (79.0%), m.p. 133±1348C, [a]546 ˆ 8.68 (c ˆ
[14] R.A. Johnson, K.B. Sharpless, in: I. Ojima (Ed.), Catalytic
Asymmetric Synthesis, VCH, New York, 1993, pp. 103±158.
[15] N.O. Brace, J. Fluorine Chem. 20 (1982) 313.
2.42 g/100 ml, F-hexyl-ethanol). NMR ((CF3)2CDOD) d:
1H: 2.05±2.35 m (8H) [H2-2 and H2-3]; 4.33±4.48 m (4H)
[Hx,y-1]; 4.54 s (2H) [H±(CH±O)]; 13C: 21.6 t (3JCF <4 Hz)
(C-2); 29.5 (2JCF ˆ 22 Hz) (C-3); 68.5 (C-1), 74.1 (C±(CH±
O)), 174.4 (C=O); 19F: 81.6 m (3F) [CF3]; CF2 resonances
are 114.5 m (2F), 121.5 m (10F), 122.6 m (2F),
123.5 m (2F), 126.3 m (2F). FT-IR (KBr) ꢀ (cm 1):
3540.7 (OH), 2966.1 (CH), 1743.2 (C=O); 1210.0 (CF).
HRMS (FAB, m/z) calculated for C30H17F42O6,
[16] M. Kotora, M. Hajek, B. Ameduri, B. Boutevin, J. Fluorine Chem.
68 (1994) 49.
[17] Y. Ding, G. Zhao, W. Huang, Tetrahedron Lett. 34 (1993) 1321.
[18] J.D. Park, F.F. Rogers, J.R. Lacher, J. Org. Chem. 26 (1961) 2089.
[19] du Pont de Nemours, Chem. Abstr. 96 (1982) 51826; Jpn. Kokai
Tokkyo Koho JP 81,125,394 (1981), US Appl. 119,148 (1980).
[20] S.E. Krahler (du Pont de Nemours), Chem. Abstr. 102 (1985)
221011; US 4,489,006 (1984).
‡
‡
 Â
[21] I.T. Horvath, G. Kiss, R.A. Cook, J.E. Bond, P.A. Stevens, J. Rabai,
(M ‡ H) ˆ 1271.0354, found (M ‡ 1) ˆ 1271.0308.
E.J. Mozeleski, J. Am. Chem. Soc. 120 (1998) 3133.
Â
Â
[22] I.T. Horvath, J. Rabai (Exxon Research and Engineering Co.), Chem.
Abstr. 123 (1995) 87349; US 5,463,082 (1995).
[23] N.O. Brace, L.W. Marshall, C.J. Pinson, G. Wingerden, J. Org.
Chem. 49 (1984) 2361.
Acknowledgements
[24] J.O. Metzger, R. Mahler, A. Schmidt, Liebigs Ann. Org. Bioorg.
Chem. 5 (1996) 693.
This work was supported by the Hungarian Scienti®c
Research Foundation (OTKA No. T 022169).