Acid-promoted direct electrophilic trifluoromethylthiolation of phenols

Article abstract of DOI:10.1039/c4ob02633k

The electrophilic aromatic ring trifluoromethylthiolation of various substituted phenols was accomplished using PhNHSCF₃ (N-trifluoromethylsulfanyl)aniline, (1) in the presence of BF₃·Et₂O (2) or triflic acid as the promoter. The functionalization was exclusively para-selective; phenols unsubstituted in both the ortho- and para positions solely gave the para-substituted SCF₃-products in all cases, while para-substituted phenols gave the ortho-substituted SCF₃-products. 3,4-Dialkyl substituted phenols yielded the corresponding products according to the Mills-Nixon effect, and estrone and estradiol furnished biologically interesting SCF₃-analogues. The highly reactive catechol and pyrogallol substrates gave the expected products smoothly in the presence of BF₃·Et₂O, whereas less reactive phenols required triflic acid. 2-Allylphenol gave the expected p-SCF₃ analogue, which underwent an addition/cyclization sequence and furnished a new di-trifluoromethylthio substituted 2,3-dihydrobenzofuran derivative. Some additional transformations of 4-(trifluoromethylthio)phenol with NBS, NIS, HNO₃, HNO₃/H₂SO₄ and 4-bromobenzyl bromide were performed giving bromo-, iodo-, nitro- and benzyl substituted products. The latter derivative underwent Suzuki-Miyaura coupling with phenylboronic acid.

Full text of DOI:10.1039/c4ob02633k

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Page 1 of 22
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Acid-promoted direct electrophilic trifluoromethylthiolation of phenols
Marjan Jereb* and Kaja Gosak
Department of Organic Chemistry, Faculty of Chemistry and Chemical Technology, Večna pot 113, 1000 Ljubljana, Slovenia
Tel.: (++386) 1 479 8577 Fax: (++386) 1 241 9144, Eꢀmail: marjan.jereb@fkkt.uniꢀlj.si
† Electronic supplementary information (ESI) available: Copies of 1H, 13C and 19F NMR spectra of all products.
Graphical abstract
Textual abstract
Highly selective and effective, acidꢀpromoted, electrophilic trifluoromethylthiolation of phenols is described.
The electrophilic aromatic ring trifluoromethylthiolation of variously substituted phenols was accomplished by
PhNHSCF3 (Nꢀtrifluoromethylsulfanyl)aniline 1 in the presence of BF3·Et2O 2 or triflic acid as promoters. The
functionalization was exclusively paraꢀselective; the phenols bearing unsubstituted both the orthoꢀ and para
positions in all cases solely gave the paraꢀsubstituted SCF3ꢀproducts, while the paraꢀsubstituted phenols gave
the orthoꢀsubstituted SCF3ꢀproducts. 3,4ꢀDialkyl substituted phenols yielded the corresponding products
according to the MillsꢀNixon effect, and estrone and estradiol furnished biologically interesting SCF3ꢀanalogues.
The highly reactive catechol and pyrogallol gave the expected products smoothly in the presence of BF3·Et2O,
whereas less reactive phenols required triflic acid. 2ꢀallylphenol gave the expected pꢀSCF3 analogue, which
underwent addition/cyclization sequence and furnished
a new diꢀtrifluoromethylthio substituted 2,3ꢀ
dihydrobenzofurane derivative. Some additional transformations of 4ꢀ(trifluoromethylthio)phenol with NBS,
NIS, HNO3, HNO3/H2SO4 and 4ꢀbromobenzyl bromide were performed giving bromoꢀ, iodoꢀ, nitroꢀ and benzyl
substituted products. The latter derivative underwent SuzukiꢀMiyaura coupling with phenylboronic acid.
Introduction
The introduction of a fluorine atom or a fluorineꢀcontaining substituent into an organic
molecule often favorably modulates the compounds’ properties, thus making new functional
and advanced materials.1,2,3,4,5,6 The fluorinated organic molecules frequently possess
enhanced stability, binding affinity and biological activity in comparison with their nonꢀ
fluorinated precursors.7,8 The trifluoromethyl group shares an exceedingly important part in
the biologically relevant molecules, and number of the newly introduced trifluoromethylated
substances in the pharmaceutical and medicinal chemistries has been growing considerably.
9,10,11
Consequently, there has been a strong interest in the direct introduction of CF3ꢀ group
1

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into organic molecules regardless of the approach via radical, nucleophilic or electrophilic
mode, thus making trifluoromethylation a current topic of great interest.12,13,14,15,16,17,18,19
An interesting variety of CF3ꢀ group is trifluoromethylthiol group SCF3ꢀ, which considerably
contributes to the enhanced lipophilicity, and is an indispensable moiety in the agrochemistry
and in medicinal chemistry;20 however its introduction received considerably less attention
than CF3ꢀ group. The 2’ꢀSCF3 substituted uridine derivative was found to be a powerful label
for probing structure and function of RNA by 19F NMR spectroscopy.21
Recently, significant progress in the introduction of SCF3 moiety has been achieved.22 The
introduction of the SCF3ꢀ group could be direct with CF3SCl23 or (CF3)2S,24 (extremely
noxious and hazardous gases that are not suitable for nonꢀspecialized laboratories) or indirect
i.e. by interconversion of functional groups25. Nucleophilic and radical sources of SCF3 group
are often copperꢀ26 or silverꢀbased27 metallic reagents, [NH4][SCF3];28 furthermore,
trifluoromethylthiolation can also be realized with a combination of two different sources of
sulfur functionality and CF3 group.29 In particular, the popularity of electrophilic
trifluoromethylthiolation has grown remarkably in the recent years; the new period began
with the work of Billard, Langlois and coworkers.30 They prepared PhNHSCF3 and its
derivatives: an easy handling electrophilic SCF3ꢀtransfer agent into alkenes and alkynes,31
indoles,32 tryptamines,33 organometallic species,34 amines,35 and allyl silanes.36 In addition,
terminal alkynes were trifluoromethylthiolated in the presence of a catalytic amount of base.37
Internal alkynes reacted with PhNHSCF3 yielding the corresponding 3ꢀ((trifluoromethyl)thio
derivatives of indoles,38 benzofuranes, benzothiophenes39 and 1Hꢀisochromenꢀ1ꢀones.40
Similarly, 4ꢀ((trifluoromethyl)thio)ꢀ2Hꢀbenzo[e][1,2]thiazine 1,1ꢀdioxides were efficiently
prepared in the presence of BiCl3 in dichloroethane.41 An interesting trifluoromethanesulfonyl
hypervalent iodonium ylide able to deliver the trifluoromethylthiol group was developed
recently.42
Nꢀ(trifluoromethylthio)succinimide
was
utilized
in
Pdꢀcatalyzed
trifluoromethylthiolation of arenes,43 while an inꢀsitu formed reagent from AgSCF3 and NCS
was employed in functionalization of alkynes.44 A new, thioperoxide45,46 type of electrophilic
trifluoromethylthiolating reagent was able to react with βꢀketoesters, boronic acids,47 alkynes
and aliphatic carboxylic acids,48 giving the corresponding SCF3ꢀsubstituted products. This
thioperoxide reagent in combination with TMSOTf was also found to be a powerful activating
agent of different thioglycosides;49 additionally, the thioperoxide reagent was used in
enantioselective
catalytic
trifluoromethylthiolations50
as
well
as
Nꢀ
trifluoromethylthiophthalimide51 and an AgSCF3/trichloroisocyanuric acid system.52 The
latter system was also utilized in the synthesis of 3ꢀ((trifluoromethyl)thio)ꢀ4Hꢀchromenꢀ4ꢀ
2

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ones.53 Electrophilic trifluoromethylthiolation of various carbonyl compounds54 and
aromatics55 was accomplished by a new Nꢀ((trifluoromethyl)thio)benzenesulfonamide type of
reagent. Nꢀtrifluoromethylthiosaccharin was developed recently and utilized in the
trifluoromethylation of alcohols, amines, thiols, electronꢀrich aromatics, aldehydes, ketones,
acyclic βꢀketoesters and alkynes.56
PhNHSCF3 (Nꢀtrifluoromethylsulfanyl)aniline 1 is a simple and easyꢀhandling electrophilic
reagent for the direct introduction of the SCF3ꢀ group into organic molecules. Its electrophilic
power usually requires activation with appropriate promoters of the Lewis or Brønsted type.
Its reactivity is mostly unexplored, and we decided to test it on phenols, since there are many
biologically relevant phenols i.e. steroids of estrone type, epinephrine, thymol and others. We
report on a direct and remarkably highly regioselective trifluoromethylthiolation of phenols
with PhNHSCF3 in combination with boron trifluoride etherate complex and triflic acid.
Results and disscussion
Initially, the reaction conditions were examined on phenol 3a as a model substrate; the results
are summarized in Table 1. Initially 3a was reacted with 1 without activator, and remained
unreacted (Table 1, entry 1). BF3·Et2O and pꢀTsOH·H2O were found to be rather unpromising
promoters for this reaction (entries 2–5).
Table 1 Optimization of the reaction conditionsa
Entry
Activator
Amount
(equiv.)
Conversion
(%)b
1
2
3
4
5
6
7
8
9
/
/
0
0
0
0
0
0
30
BF3·Et2O
2.5
5
2.5
5
1.5
2
p-TsOH·H2O
CH3SO3H
TfOH
1.2
1.3
91
100 (77)c
a
Conditions: 3a (1 mmol), 1 (1.2–1.3 mmol),
b
activator, DCM (10 mL), 14 h, rt. Conversion
determined by 1H NMR. c Isolated yield.
We decided to examine the role of considerably stronger activators, i.e. CH3SO3H (MSA) and
triflic acid (TfOH). MSA was found somewhat better activator (entries 6 and 7), while TfOH
was the promoter of choice (entries 8 and 9). In all cases, 4ꢀtrifluoromethylthiophenol 4a was
obtained, and no ortho substitution was noted. Results of the functionalization of different
phenols are presented in Table 2. 2ꢀmethylphenol 3b and 3ꢀmethylphenol 3c both yielded 4ꢀ
3

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SCF3ꢀsubstituted products 4b and 4c exclusively (Table 2, entries 1 and 2). 4ꢀmethylphenol
3d and 4ꢀiꢀpropylphenol 3e yielded the corresponding 2ꢀSCF3ꢀsubstituted products 4d and 4e
as the sole products. In the cases of 2ꢀtꢀbutylphenol 3f and 4ꢀtꢀbutylphenol 3g, ipso
substitution could have been observed; however, 4ꢀSCF3ꢀ 4f and 2ꢀSCF3ꢀsubstituted product
4g were formed as the sole products (entries 5 and 6). Similarly, 2ꢀbenzylphenol 3h yielded 4ꢀ
SCF3ꢀsubstituted product 4h, while no ipso substitution was observed. 4ꢀphenylphenol 3i was
regioselectively transformed into its 2ꢀSCF3ꢀsubstituted product 4i. Reactions of 2,5ꢀ
dimethylphenol 3j and 2,6ꢀdimethylphenol 3k cleanly furnished their 4ꢀSCF3ꢀsubstituted
derivatives 4j and 4k (entries 9 and 10). 2,3,5ꢀtrimethylphenol 3l and 2,3,6ꢀtrimethylphenol
3m gave their 4ꢀSCF3ꢀsubstituted derivatives 4l and 4m as the sole products (entries 11 and
12).
Table 2 Acidꢀpromoted trifluoromethylthiolation of phenolsa
Entry
1
Reactant
Product
Yield
(%)b
o-cresol 3b
81
79
80
2
3
m-cresol 3c
p-cresol 3d
4
4-i-propylphenol
82
3e
5
6
2-t-butylphenol
64
87
3f
4-t-butylphenol
3g
7
8
9
2-benzylphenol
86
48
90
3h
4-phenylphenol
3i
2,5-
dimethylphenol
3j
4

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10
11
12
13
2,6-
dimethylphenol
3k
91
84
93
83
2,3,5-
trimethylphenol
3l
2,3,6-
trimethylphenol
3m
2,4,6-
trimethylphenol
3n
a
Conditions: 3 (1 mmol), 1 (1.2–1.3 mmol), TfOH (1.2–5
mmol), DCM (10 mL), 14 h, rt. b Isolated yield.
2,4,6ꢀtrimethylphenol 3n was an interesting substrate, because all potentially reacting
positions were substituted. None of the possible ipso adducts was observed, but 2,4,6ꢀ
trimethylꢀ3ꢀtrifluoromethylthiophenol 4n was isolated as a sole product (entry 13).
Next, we examined the reactivity of 3,4ꢀdimethylphenol 5a, 5ꢀindanol 5b and 5,6,7,8ꢀ
tetrahydroꢀ2ꢀnaphthol 5c (Scheme 1).
Scheme 1 The effect of structure of 3,4ꢀdialkyl substituted phenols on trifluoromethylthiolation.
Such compounds possess unequally reactive ortho positions; the phenomenon is known as the
MillsꢀNixon effect.57 5a furnished the expected 6a as the major product, while no 6aa was
detected. Instead, double functionalization took place, yielding 6a’ as a minor product. The
relative distribution ratio 6a/6a’ was 94/6. 5b yielded only one expected product 6b; whereas
no 6bb was detected. 5c reacted in accordance with the anticipated reactivity giving 6c and
6cc in a relative ratio of 56/44. Regioselectivity of trifluoromethylthiolation of 3,4ꢀ
dimethylphenol and 5ꢀindanol is similar to the bromination reaction,58 while bromination of
5,6,7,8ꢀtetrahydroꢀ2ꢀnaphthol was more selective (78/22) than trifluoromethylthiolation.
Nitration of 3,4ꢀdimethylphenol (57/43) and 5ꢀindanol (58/42) with NaNO2/H2O2/H2SO4 was
less regioselective than trifluoromethylthiolation, while nitration was more selective in the
case of 5,6,7,8ꢀtetrahydroꢀ2ꢀnaphthol (63/37).59
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It is known that PhNHSCF3 reacts with alkenes,31 and we examined the reactivity of 2ꢀ
allylphenol 7 due to the two diverse potential reacting sites (Scheme 2).
Scheme 2 Double functionalization of 2ꢀallylphenol with PhNHSCF3.
We established that 7 reacted with 1 in the presence of TfOH as phenol and as alkene, thus
proposing a secondary carbocationic intermediate 8. Reaction proceeded in dichloromethane
in the absence of a good nucleophile, and phenolic oxygen atom took part in an
intramolecular cyclization thus producing a fiveꢀmembered product 9 as a novel type of
trifluoromethylthiolated product. It appears that the stability of 8 was of crucial importance
for the reaction selectivity. The other possible sixꢀmembered isomeric product originating
from the reversed addition of PhNHSCF3 to the double bond that would have generated a
primary carbocation, was not observed. The structure of 9 was confirmed with NMR
spectroscopy, and the key experiment was DEPT 135. The carbon atom attached to the –SCF3
group appeared as a quartet in the same phase with the second aliphatic signal, whereas the
third aliphatic signal was in an opposite phase. This was a clear indication that –SCF3 group
was attached to the CH2ꢀ, and not to the CHꢀ group.
The reactivity of highly reactive bicyclicꢀ and alkoxyꢀ and hydroxyphenols with PhNHSCF3
is summarized in Table 3.
a
Table 3 Reactivity of the highly electronꢀrich phenols with PhNHSCF3
Entry
1
Reactant
Product
Yield
(%)b
2-methoxy-4-
97
methylphenol 10a
2
2,6-dimethoxyphenol
84
10b
6

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OH
3
4
5,6,7,8-
tetrahydronaphth-1-ol
10c
93
SCF3
OH
95
1-naphthol 10d
2-naphthol 10e
SCF3
5
6
7
82
2,7-
dihidroxynaphthalene
10f
86
79
2',6'-
dihydroxyacetophenone
10g
8
9
catechol 10h
70
88
4-methylcatechol 10i
10
11
resorcinol 10j
pyrogallol 10k
80
60
a Conditions: 10 (1 mmol), 1 (1.2–1.3 mmol), TfOH (1.3–4 mmol) or
2 (2–3 mmol), DCM (10 mL), 14 h, rt. b Isolated yield.
2ꢀmethoxyꢀ4ꢀmethylphenol 10a produced 6ꢀSCF3 analogue 11a as a sole product, while 2,6ꢀ
dimethoxyphenol 10b selectively yielded its 3ꢀSCF3 derivative 11b (Table 3, entries 1 and 2).
5,6,7,8,ꢀtetrahydroꢀ1ꢀnaphthol 10c was regioselectively transformed into its 4ꢀSCF3 analogue
11c in good yield. Transformation of 1ꢀnaphthol 10d and 2ꢀnaphthol 10e was completely
selective in both cases. The former led to its 4ꢀSCF3 derivative 11d, whereas the latter to its 1ꢀ
SCF3 analogue 11e (entries 4 and 5). Additionally, 2,7ꢀdihydroxynaphthalene 10f was tested
due to the possibility of double functionalization. Indeed, 1,8ꢀdiSCF3 derivative 11f was
isolated as a single product in good yield. 2’,6’ꢀdihydroxyacetophenone 10g was smoothly
converted into its 3ꢀSCF3 derivative 11g (entry 7). In continuation, some naturally occurring
phenols were successfully transformed into their trifluoromethylthio analogues. Catechol 10h
selectively produced its 4ꢀSCF3 derivative 11h, and 4ꢀmethylcatechol 10i yielded its 5ꢀSCF3
derivative 11i exclusively (entries 8 and 9). Functionalization of resorcinol 10j smoothly
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afforded its 4ꢀSCF3 analogue 11j in a good yield. Highly oxidationꢀprone pyrogallol 10k was
also efficiently transformed into its 3ꢀSCF3 derivative 11k (entry 11). It could be concluded
that the reaction system PhNHSCF3/activator is compatible with highly electronꢀrich phenols
and the introduction of ꢀSCF3 groups took place efficiently without noticeable portion of
oxidation.
In addition, we tested some of the biologically relevant molecules possessing the phenolic
functionality (Scheme 3). 3,4ꢀ(methylenedioxy)phenol 12a as highly reactive substance
afforded the corresponding 6ꢀSCF3 derivative 13a as a sole product. The reaction was
completed in 20 minutes, and the product 13a was obtained in good yield. 6ꢀhydroxyꢀ1,3ꢀ
benzoxathiolꢀ2ꢀone 12b was successfully converted into its 5ꢀSCF3 derivative 13b in spite of
an acidꢀsensitive oxathiolone functional group. This is a good demonstration that the acidic
reaction system is also compatible with the sensitive functionalities. Thymol 12c was
effectively transformed into its 4ꢀSCF3 derivative 13c in high yield. Estrone 12d and estradiol
12e are important steroid hormones bearing the phenolic functionality. Both were
regioselectively transformed into the corresponding oꢀSCF3 analogues 13d, 13dd, 13e and
13ee (Scheme 4).
OH
OH
PhNHSCF3, TfOH
DCM, 0.33 - 14 h, rt
R
R
SCF3
12a - 12c
13a - 13c
F3CS
F3CS
O
S
O
O
O
HO
HO
13a (65 %)
13b (64 %)
OH
13c (98%)
SCF3
Scheme 3 Reactivity of some biologically active phenols with PhNHSCF3.
Regioselectivity of functionalization of estrone is similar to the nitration reaction; however,
the selectivity was higher in the case of nitration.59
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Scheme 4 Electrophilic trifluoromethylthiolation of estrogenic hormones with PhNHSCF3.
In addition, some further functionalizations of 4ꢀ(trifluoromethylthio)phenol 4a were studied
(Scheme 5). The strong electronꢀwithdrawing nature of the trifluoromethylthio group
significantly influences the reactivity of such compounds. 4a was nitrated with 65% HNO3
under solventꢀfree reaction conditions in 14 hours at 30–40°C, selectively yielding monoꢀ
nitrated product 14, and no overꢀnitration took place. The reason for the perfect selectivity is
that dinitration required considerably more rigorous reaction conditions to occur: 70–80° C
and the presence of concentrated sulfuric acid. Dinitrophenol derivative 15 was isolated in a
78% yield. The introduction of halogens is highly significant because of the possibility of
additional reactions, particularly various crossꢀcouplings. Bromination of 4a with NBS in 1ꢀ
methylꢀ3ꢀbutylimidazolium tetrafluoroborate [Bmim]BF4 in the presence of small amount of
water60 afforded dibromo analogue 16 in 94% yield. Iodination was performed using the same
reaction medium, producing diiodo derivative 17. Preparation of diphenyl ether derivative 18
was accomplished using tꢀBuOK and diphenyliodonium triflate61 in THF.
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Scheme 5 Reactivity of 4ꢀ(trifluoromethylthio)phenol 4a with different reagents
Finally, 4a was converted into its 4ꢀbromobenzyl ether 19, which reacted with phenyl boronic
acid in the presence of Pd(OAc)2 and PPh3 yielding a crossꢀcoupled derivative 20 in a good
yield.
A detailed reaction mechanism is not known; however, the most likely reaction pathway is an
electrophilic one. The reaction selectivity paraꢀ and orthoꢀ is one of the strong arguments in
favor of the electrophilic pathway. Reagent PhNHSCF3 1 is principally an amine and
relatively a weak electrophilic reagent. The strong Brønsted acid TfOH seemingly protonated
1, thus forming a corresponding salt with considerably more pronounced polarization between
nitrogen and sulfur atom. The strong electron deficiency of nitrogen atom presumably tends to
attract the electron density; thus making a weaker bond C–S and stronger sulfur electrophile
able to react with phenols (Scheme 6).
Scheme 6 A plausible reaction mechanism
10

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Trifluoromethylthiolation of mꢀcresol in the presence of a free radical TEMPO62,63 took place
the same as without TEMPO. This is another indication that radical pathway is not very likely
to be a chief reaction course.
Conclusions
In summary, we have developed a new, highly regioselelective and efficient method for the
trifluoromethylthiolation of phenols. The reaction pathway is most likely to be an
electrophilic substitution. The method is suitable for nonꢀspecialized laboratories because the
transformation was accomplished with PhNHSCF3 and without extremely noxious CF3SCl
and (CF3)2S. An additional advantage was operational simplicity; specifically, reactions were
performed with nonꢀdried dichloromethane in an air atmosphere at room temperature. The
reaction selectivity was remarkably high; when both paraꢀ and orthoꢀ sites were
unsubstituted, only paraꢀ functionalization took place. When the paraꢀ position was already
substituted, the functionalization of the orthoꢀ site took place, and no ipsoꢀsubstitution was
noted. The reaction conditions were also demonstrated to be compatible with the acid
sensitive i.e. thioxolone moiety.
Experimental Section
General information
All transformations were carried out in untreated dichloromethane under an air atmosphere
with stirring at room temperature. Starting phenols and other chemicals were obtained from
commercial sources; PhNHSCF3 1 was prepared using the literature procedure.30 Crude
products were purified by column chromatography on silica gel (63–200 ꢁm, 70–230 mesh
ASTM; Fluka). TLC was performed on Merckꢀ60ꢀF254 plates using mixtures of hexane and
diethyl ether. The melting points were determined in openꢀcapillaries on Büchi 535 apparatus
1
19
and are uncorrected. All products were characterized with H, 13C and F NMR spectra, IR,
1
HRMS and/or elemental analysis, and also with the melting points when solid. The H and
13C NMR spectra were recorded on Bruker Avance 300 DPX and Bruker Avance III 500
instruments, while 19F NMR spectra were only recorded on the latter instrument. Chemical
shifts are reported in δ (ppm) values relative to δ = 7.26 ppm in CDCl3 and δ = 2.05 ppm in
1
acetoneꢀd6 for H NMR, and to the central line of CDCl3 (δ = 77.00 ppm) and to the central
line of acetoneꢀd6 (δ = 30.83 ppm) for 13C NMR. 19F NMR spectra are referenced to CFCl3 (δ
= 0.00 ppm).
Representative procedure of acid-promoted trifluoromethylthiolaton of phenols
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To a solution of phenol (1 mmol or 0.5 mmol in the case of steroids) in dichloromethane (10
mL), PhNHSCF3 (1.2–1.3 equiv.) was added and the corresponding amount of triflic acid
(1.2–5 equiv.) or BF3·Et2O (2–3 equiv.). The resulting mixture was stirred at room
temperature up to 16 h. In most cases, the starting phenol was fully consumed, as determined
by TLC. The reaction mixture was diluted with 10 ml of dichloromethane, washed with 10%
solution of NaHCO3, water and dried over anhydrous Na2SO4. Crude reaction mixture was
subjected to column chromatography after removal of solvent. In numerous cases, it was only
‘filtration’ over silica gel, because of excellent reaction selectivity.
Reactivity of 4a with different reagents
a) Reaction with HNO3
To 4ꢀ(trifluoromethylthio)phenol 4a (0.4 mmol, 77 mg) HNO3 (65%, 1.6 mmol, 156 mg) was
added and the resulting reaction mixture was stirred at 30–40°C overnight. TLC revealed the
full consumption of 4a. The reaction mixture was cooled to room temperature, and product
was extracted three times with 5 mL of dichloromethane, two times with water, and dried
over anhydrous Na2SO4. Pure product 14 (84 mg, 87%) was obtained as a yellow solid after
column chromatography (hexane/diethyl ether).
b) Reaction with HNO3/H2SO4
HNO3 (65%, 1.6 mmol, 156 mg) was added to 4a (0.4 mmol, 77 mg) and the resulting
reaction mixture was stirred at 30–40 °C overnight. TLC revealed the full consumption of 4a.
HNO3 (65%, 1.6 mmol, 156 mg) and concentrated H2SO4 (98%, 0.8 mmol, 80 mg) were
added and reaction mixture was stirred at 70–80 °C overnight. TLC showed disappearance of
mononitro product. The reaction mixture was cooled to room temperature, and the product
was extracted three times with 5 mL of dichloromethane and brine. The organic phase was
dried over anhydrous Na2SO4, and solvent evaporated. After column chromatography
(hexane/diethyl ether) pure product 15 (88 mg, 77%) was obtained as a yellow solid.
c) Reaction with NBS in [Bmim]BF4
Reaction was performed according to the reported procedure.60 4a (0.3 mmol, 58 mg) reacted
with Nꢀbromosuccinimide (0.72 mmol, 128 mg) in 20 minutes. Crude reaction mixture was
chromatographed (hexane/diethyl ether), and yellowish solid product 16 (98 mg, 94%) was
obtained.
d) Reaction60 with NIS in [Bmim]BF4
The same reaction procedure and amounts as in the case of NBS. From 4a (0.3 mmol, 58 mg)
after column chromatography 17 (120 mg, 90%) was obtained as a grey solid.
e) Reaction with Ph2IOTf/t-BuOK
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Transformation was performed according to the literature.61 A solution of 4a (0.4 mmol, 77
mg) in dry THF (1 mL) under argon atmosphere was cooled to 0 °C and tꢀBuOK (0.5 mmol,
56 mg) was added, and the mixture was stirred for 15 minutes at 0 °C. The reaction mixture
was warmed to 40 °C, diphenyliodonium triflate (0.6 mmol, 258 mg) was added and the
mixture stirred for three hours at 40 °C. The crude product was chromatographed
(hexane/diethyl ether), and a colorless oily product 18 (69 mg, 64%) was obtained.
f) Reaction with 4-bromobenzyl bromide/K2CO3
A mixture of 4a (0.4 mmol, 77 mg), 4ꢀbromobenzyl bromide (0.4 mmol, 100 mg) and K2CO3
(0.48 mmol, 66 mg) was stirred one hour at 80 °C in acetonitrile. TLC showed consumption
of the starting phenol 4a. A reaction mixture was cooled to room temperature, and the solvent
was removed under vacuum. The product was extracted three times with 5 mL of
dichloromethane, with water and dried over anhydrous Na2SO4. A solvent was removed and
the product chromatographed (hexane/diethyl ether), thus giving bright yellow product 19
(137 mg, 95%).
g) Suzuki-Miyaura coupling
Phenylboronic acid (0.275 mmol, 33 mg) was added to a solution of 18 (0.25 mmol, 90 mg)
in isopropanol (5 mL) and purged with argon for 10 minutes. Pd(OAc)2 (0.022 mmol, 5 mg),
triphenylphosphine (0.095 mmol, 25 mg), a degassed solution of K2CO3 (1.5 mL, 2M) and
deionized water (1 mL) were added consecutively. The resulting mixture was stirred for 1
hour at reflux temperature, and TLC showed consumption of 18. The mixture was cooled,
concentrated under vacuum, diluted with dichloromethane (10 mL) and water (10 mL). After
separation of phases, the aqueous phase was additionally extracted three times with 5 mL of
dichloromethane. The combined organic phase was dried over anhydrous Na2SO4, filtered and
solvent removed. The crude product was chromatographed (hexane/diethyl ether), thus
yielding white solid 20 (66 mg, 73%).
Spectroscopic and analytic data
°
4ꢀ(Trifluoromethylthio)phenol 4a.56 Colorless solid; mp 52.9–53.5 C; (1 mmol 3a, 1.3 mmol PhNHSCF3, 1.3
mmol TfOH); 1H NMR (500 MHz, CDCl3): δ 5.23 (br s, 1H), 6.84–6.90 (m, 2H), 7.51–7.57 (m, 2H); 13C NMR
(125 MHz, CDCl3): δ 115.2 (q, J = 2.0 Hz), 116.5, 129.5 (q, J = 308.1 Hz), 138.6, 158.0; 19F NMR (470 MHz,
CDCl3): δ ꢀ44.4 (s, SCF3); IR: 3221, 1670, 1584, 1493, 1436, 1364, 1346, 1226, 1083, 826, 754, 650 cmꢀ1; ESIꢀ
HRMS m/z calcd for C7H4F3OS (M−H)− 192.9935, found 192.9945.
2ꢀMethylꢀ4ꢀ(trifluoromethylthio)phenol 4b. Yellow, viscous liquid; (1 mmol 3b, 1.3 mmol PhNHSCF3, 1.3
mmol TfOH); 1H NMR (500 MHz, CDCl3): δ 2.26 (s, 3H), 5.07 (br s, 1H), 6.79 (d, J = 8.3 Hz, 1H), 7.38 (dd, J
= 8.3, 1.8 Hz, 1H), 7.42 (d, J = 1.8 Hz, 1H); 13C NMR (125 MHz, CDCl3): δ 15.6, 114.7 (q, J = 1.7 Hz), 115.9,
125.3, 129.6 (q, J = 308.1 Hz), 136.0, 139.4, 156.3; 19F NMR (470 MHz, CDCl3): δ ꢀ44.4 (s, SCF3); IR: 3409,
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1588, 1495, 1401, 1261, 1087, 891, 814, 755 cmꢀ1; ESIꢀHRMS m/z calcd for C8H6F3OS (M−H)− 207.0097,
found 207.0095.
3ꢀMethylꢀ4ꢀ(trifluoromethylthio)phenol 4c. Orange, viscous liquid; (1 mmol 3c, 1.3 mmol PhNHSCF3, 1.2 mmol
TfOH); 1H NMR (500 MHz, CDCl3): δ 2.49 (s, 3H), 5.13 (br s, 1H), 6.70 (dd, J = 8.4, 2.7 Hz, 1H), 6.80 (d, J =
2.7 Hz, 1H), 7.53 (d, J = 8.4 Hz, 1H); 13C NMR (125 MHz, CDCl3): δ 21.3, 114.1, 114.8 (q, J = 1.5 Hz), 117.8,
129.8 (q, J = 308.6 Hz), 140.3, 146.4, 158.1; 19F NMR (470 MHz, CDCl3): δ ꢀ44.0 (s, SCF3); IR: 3348, 1594,
1575, 1480, 1453, 1294, 1240, 1098, 1046, 947, 857, 812, 754, 731 cmꢀ1; ESIꢀHRMS m/z calcd for C8H6F3OS
(M−H)− 207.0097, found 207.0095.
°
4ꢀMethylꢀ2ꢀ(trifluoromethylthio)phenol 4d. Light yellow solid; mp 42.5–43.1 C; (1 mmol 3d, 1.3 mmol
PhNHSCF3, 2 mmol TfOH); 1H NMR (500 MHz, CDCl3): δ 2.30 (s, 3H), 6.14 (s, 1H), 6.97 (d, J = 8.4 Hz, 1H),
7.24 (dd, J = 8.4, 1.7 Hz, 1H), 7.36 (d, J = 1.7 Hz, 1H); 13C NMR (125 MHz, CDCl3): δ 20.2, 107.7 (q, J = 1.2
Hz), 115.9, 128.7 (q, J = 310.5 Hz), 130.9, 135.1, 138.0, 155.9; 19F NMR (470 MHz, CDCl3): δ ꢀ43.4 (s, SCF3);
IR: 3417, 1489, 1136, 1097, 1055, 825 cmꢀ1; ESIꢀHRMS m/z calcd for C8H6F3OS (M−H)− 207.0097, found
207.0094.
4ꢀIsopropylꢀ2ꢀ(trifluoromethylthio)phenol 4e. White solid; mp 36.8–37.4 °C; (1 mmol 3e, 1.3 mmol PhNHSCF3,
2.0 mmol TfOH); 1H NMR (500 MHz, CDCl3): δ 1.23 (d, J = 6.9 Hz, 6H), 2.87 (septet, J = 6.9 Hz, 1H), 6.15 (br
s, 1H), 7.00 (d, J = 8.5 Hz, 1H), 7.30 (dd, J = 8.5, 2.1 Hz, 1H), 7.40 (d, J = 2.1 Hz, 1H) ; 13C NMR (125 MHz,
CDCl3): δ 24.0, 33.1, 107.7 (q, J = 1.2 Hz), 115.9, 128.8 (q, J = 310.5 Hz), 132.5, 135.6, 142.0, 156.0; 19F NMR
(470 MHz, CDCl3): δ ꢀ43.4 (s, SCF3); IR: 3429, 3410, 1487, 1467, 1456, 1283, 1183, 1103, 832, 728 cmꢀ1; ESIꢀ
HRMS m/z calcd for C10H10F3OS (M−H)− 235.0410, found 235.0409.
2ꢀtertꢀbutylꢀ4ꢀ(trifluoromethylthio)phenol 4f. Yellow, viscous liquid; (1 mmol 3f, 1.3 mmol PhNHSCF3, 1.2
mmol TfOH); 1H NMR (300 MHz, CDCl3): δ 1.41 (s, 9H), 5.15 (br s, 1H), 6.69 (d, J = 8.2 Hz, 1H), 7.37 (dd, J
= 8.2, 2.2 Hz, 1H), 7.53 (d, J = 2.2 Hz, 1H); 13C NMR (125 MHz, CDCl3): δ 29.3, 34.7, 114.8 (d, J = 1.8 Hz),
117.5, 129.7 (q, J = 308.1 Hz), 135.7, 136.0, 137.6, 156.7; 19F NMR (470 MHz, CDCl3): δ ꢀ44.4 (s, SCF3); IR:
3408, 2962, 1587, 1494, 1260, 1113, 1097, 1080, 815, 755 cmꢀ1; ESIꢀHRMS m/z calcd for C11H12F3OS (M−H)−
249.0566, found 249.0566.
4ꢀtertꢀbutylꢀ2ꢀ(trifluoromethylthio)phenol 4g. Yellow, viscous liquid; (1 mmol 3g, 1.3 mmol PhNHSCF3, 2
mmol TfOH) ; 1H NMR (300 MHz, CDCl3): δ 1.30 (s, 9H), 6.14 (br s, 1H), 7.00 (d, J = 8.6 Hz, 1H), 7.47 (dd, J
= 8.6, 2.4, Hz, 1H), 7.54 (d, J = 2.4 Hz, 1H); 13C NMR (125 MHz, CDCl3): δ 31.3, 34.2, 107.5 (q, J = 1.1 Hz),
115.6, 128.8 (q, J = 310.5 Hz), 131.6, 134.7, 144.5, 155.8; 19F NMR (470 MHz, CDCl3): δ ꢀ43.4 (s, SCF3); IR:
3507, 1490, 1365, 1103, 822, 755 cmꢀ1; ESIꢀHRMS m/z calcd for C11H12F3OS (M−H)− 249.0561, found
249.0566.
2ꢀBenzylꢀ4ꢀ(trifluoromethylthio)phenol 4h. Yellow, viscous liquid; (1 mmol 3h, 1.3 mmol PhNHSCF3, 1.5
1
mmol TfOH); H NMR (500 MHz, CDCl3): δ 3.98 (s, 2H), 5.12 (br s, 1H), 6.77–6.81 (m, 1H), 7.18–7.26 (m,
3H), 7.28–7.33 (m, 2H), 7.39–7.44 (m, 2H); 13C NMR (125 MHz, CDCl3): δ 36.2, 115.1 (q, J = 1.9 Hz), 116.8,
126.7, 128.5, 128.6, 128.8, 129.6 (q, J = 308.1 Hz), 136.6, 138.8, 139.4, 156.3; 19F NMR (470 MHz, CDCl3): δ ꢀ
44.4 (s, SCF3); IR: 3523, 1587, 1494, 1453, 1411, 1091, 823, 729, 697 cmꢀ1; ESIꢀHRMS m/z calcd for
C14H10F3OS (M−H)− 283.0410, found 283.0410.
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3ꢀ(Trifluoromethylthio)biphenylꢀ4ꢀol 4i. White solid; mp 101.6–101.9 °C; (1 mmol 3i, 1.3 mmol PhNHSCF3, 1.3
mmol TfOH); 1H NMR (300 MHz, CDCl3): δ 6.32 (br s, 1H), 7.16 (d, J = 8.5 Hz, 1H), 7.32–7.40 (m, 1H), 7.40–
7.49 (m, 2H), 7.50–7.58 (m, 2H), 7.68 (dd, J = 8.5, 2.2 Hz, 1H), 7.81 (d, J = 2.2 Hz, 1H) ; 13C NMR (125 MHz,
CDCl3): δ 108.7 (q, J = 1.2 Hz), 116.6, 126.7, 127.4, 128.7 (q, J = 310.7 Hz), 128.9, 133.0, 134.9, 136.5, 139.2,
157.4; 19F NMR (470 MHz, CDCl3): δ ꢀ43.2 (s, SCF3); IR: 3408, 1602, 1473, 1334, 1194, 1155, 1132, 1100,
1055, 895, 860, 763, 738, 700 cmꢀ1; ESIꢀHRMS m/z calcd for C13H8F3OS (M−H)− 269.0253, found 269.0253.
2,5ꢀDimethylꢀ4ꢀ(trifluoromethylthio)phenol 4j. Yellow, viscous liquid; (1 mmol 3j, 1.3 mmol PhNHSCF3, 1.3
1
mmol TfOH); H NMR (300 MHz, CDCl3): δ 2.22 (s, 3H), 2.45 (s, 3H), 4.91 (br s, 1H), 6.73 (s, 1H), 7.41 (s,
1H); 13C NMR (75 MHz, CDCl3): δ 15.0, 20.8, 114.3 (q, J = 1.6 Hz), 117.3, 122.6, 129.9 (q, J = 308.7 Hz),
141.1, 143.6, 156.4; 19F NMR (470 MHz, CDCl3): δ ꢀ44.0 (s, SCF3); IR: 3602, 3412, 2866, 1395, 1377, 1256,
1222, 1094, 1017, 892, 852, 754, 625 cmꢀ1; ESIꢀHRMS m/z calcd for C9H8F3OS (M−H)− 221.0253, found
221.0255.
2,6ꢀDimethylꢀ4ꢀ(trifluoromethylthio)phenol 4k. Yellow solid; mp 40.4–42.7 °C; (1 mmol 3k, 1.3 mmol
1
PhNHSCF3, 1.3 mmol TfOH); H NMR (500 MHz, CDCl3): δ 2.26 (s, 6H), 4.91 (br s, 1H), 7.28 (s, 2H); 13C
NMR (125 MHz, CDCl3): δ 15.7, 113.9 (q, J = 1.8 Hz), 124.3, 129.7 (q, J = 308.0 Hz), 137.0, 154.7; 19F NMR
(470 MHz, CDCl3): δ ꢀ44.4 (s, SCF3); IR: 3613, 3449, 1586, 1473, 1330, 1153, 1093, 876, 754, 730 cmꢀ1; ESIꢀ
HRMS m/z calcd for C9H8F3OS (M−H)− 221.0253, found 221.0253.
2,3,5ꢀTrimethylꢀ4ꢀ(trifluoromethylthio)phenol 4l. White solid; mp 82.1–82.4 °C; (1 mmol 3l, 1.3 mmol
PhNHSCF3, 1.3 mmol TfOH); 1H NMR (500 MHz, CDCl3): δ 2.19 (s, 3H), 2.50 (s, 3H), 2.55 (s, 3H), 5.02 (br s,
1H), 6.64 (s, 1H); 13C NMR (125 MHz, CDCl3): δ 12.5, 19.1, 22.3, 115.0 (q, J = 1.2 Hz), 115.1, 121.7, 130.1 (q,
J = 309.5 Hz), 144.0, 145.8, 155.5; 19F NMR (470 MHz, CDCl3): δ ꢀ43.5 (s, SCF3); IR: 3321, 1690, 1575, 1446,
1298, 1097, 1076, 858, 846, 753 cmꢀ1; ESIꢀHRMS m/z calcd for C10H10F3OS (M−H)− 235.0410, found
235.0411.
°
2,3,6ꢀTrimethylꢀ4ꢀ(trifluoromethylthio)phenol 4m. Yellow solid; mp 51.6–54.2 C (1 mmol 3m, 1.3 mmol
PhNHSCF3, 1.2 mmol TfOH); 1H NMR (300 MHz, CDCl3): δ 2.22 (s, 3H), 2.23 (s, 3H), 2.48 (s, 3H), 4.89 (br s,
1H), 7.35 (s, 1H); 13C NMR (125 MHz, CDCl3): δ 12.7, 15.5, 18.2, 114.2 (q, J = 1.5 Hz), 121.1, 123.4, 129.9 (q,
J = 308.6 Hz), 138.0, 142.0, 154.6; 19F NMR (470 MHz, CDCl3): δ ꢀ44.3 (s, SCF3); IR: 3477, 1465, 1400, 1213,
1184, 1144, 1100, 1020, 909, 754 cmꢀ1; ESIꢀHRMS m/z calcd for C10H10F3OS (M−H)− 235.0410, found
235.0412.
°
2,4,6ꢀTrimethylꢀ3ꢀ(trifluoromethylthio)phenol 4n. Light yellow solid; mp 75.5–76.4 C; (1 mmol 3n, 1.3 mmol
1
PhNHSCF3, 5 mmol TfOH); H NMR (300 MHz, CDCl3): δ 2.25 (s, 3H), 2.48 (s, 3H), 2.51 (s, 3H), 4.62 (br s,
1H), 6.99 (s, 1H); 13C NMR (75 MHz, CDCl3): δ 14.9, 16.1, 21.6, 121.3 (q, J = 1.4 Hz), 126.9, 130.1, 130.1 (q, J
= 309.4 Hz), 130.2, 137.0, 150.8; 19F NMR (470 MHz, CDCl3): δ ꢀ42.8 (s, SCF3); IR: 3365, 1470, 1378, 1299,
1151, 1096, 998, 871, 801, 753 cmꢀ1; ESIꢀHRMS m/z calcd for C10H10F3OS (M−H)− 235.0410, found 235.0408.
4,5ꢀDimethylꢀ2ꢀ(trifluoromethylthio)phenol 6a. White solid; mp 65.6–65.8 °C (1 mmol 5a, 1.3 mmol
1
PhNHSCF3, 1.2 mmol TfOH); H NMR (300 MHz, CDCl3): δ 2.20 (s, 3H), 2.26 (s, 3H), 6.06 (s, 1H), 6.88 (s,
1H), 7.30 (s, 1H); 13C NMR (125 MHz, CDCl3): δ 18.6, 20.1, 104.5 (q, J = 1.2 Hz), 117.0, 128.8 (q, J = 310.6
Hz), 129.9, 138.2, 144.0, 156.0; 19F NMR (470 MHz, CDCl3): δ ꢀ43.8 (s, SCF3); IR: 3398, 3372, 1480, 1313,
1210, 1145, 1101, 1022, 871 cmꢀ1; ESIꢀHRMS m/z calcd for C9H8F3OS (M−H)− 221.0253, found 221.0250.
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°
3,4ꢀDimethylꢀ2,6ꢀbis(trifluoromethylthio)phenol 6a'. White solid; mp 48.5–48.9 C; (1 mmol 5a, 1.3 mmol
1
PhNHSCF3, 1.2 mmol TfOH); H NMR (300 MHz, CDCl3): δ 2.28 (s, 3H), 2.53 (s, 3H), 6.86 (s, 1H), 7.53 (s,
1H); 13C NMR (75 MHz, CDCl3): δ 19.0, 20.1, 107.0 (q, J = 1.7 Hz), 110.9 (q, J = 1.3 Hz), 128.9 (q, J = 311.3
Hz), 129.1 (q, J = 310.1 Hz), 130.6, 142.7, 149.1, 158.7; 19F NMR (470 MHz, CDCl3): δ ꢀ42.6 (s, SCF3); ꢀ43.2
(s, SCF3); IR: 3455, 1440, 1391, 1271, 1092, 904, 755, 671 cmꢀ1; Anal Calcd for C10H8F6OS2: C, 37.27; H, 2.50.
Found: C, 37.41; H, 2.48.
°
6ꢀ(Trifluoromethylthio)ꢀ2,3ꢀdihydroꢀ1Hꢀindenꢀ5ꢀol 6b. White solid; mp 73.7–74.5 C; (1 mmol 5b, 1.3 mmol
1
PhNHSCF3, 3 mmol BF3·Et2O); H NMR (500 MHz, CDCl3): δ 2.09 (quintet, J = 7.4 Hz, 2H), 2.85 (t, J = 7.4
Hz, 2H), 2.90 (t, J = 7.4 Hz, 2H), 6.19 (br s, 1H), 6.94 (s, 1H), 7.37 (s, 1H); 13C NMR (125 MHz, CDCl3): δ
25.7, 31.7, 33.3, 105.1 (q, J = 1.2 Hz), 111.8, 128.8 (q, J = 310.7 Hz), 133.0, 137.3, 152.0, 156.6; 19F NMR (470
MHz, CDCl3): δ ꢀ43.9 (s, SCF3); IR: 3418, 3401, 1471, 1440, 1430, 1330, 1129, 1103, 897, 879 cmꢀ1; ESIꢀ
HRMS m/z calcd for C10H8F3OS (M−H)− 233.0248, found 233.0253.
°
3ꢀ(Trifluoromethylthio)ꢀ5,6,7,8ꢀtetrahydronaphthalenꢀ2ꢀol 6c. White solid; mp 52.8–53.0 C; (1 mmol 5c, 1.3
1
mmol PhNHSCF3, 3 mmol BF3·Et2O); H NMR (500 MHz, CDCl3): δ 1.74–1.81 (m, 4H), 2.67–2.73 (m, 2H),
2.73–2.79 (m, 2H), 6.03 (br s, 1H), 6.78 (s, 1H), 7.25 (s, 1H); 13C NMR (125 MHz, CDCl3): δ 22.6, 22.9, 28.3,
29.6, 105.0 (q, J = 1.1 Hz), 115.8, 128.8 (q, J = 310.5 Hz), 130.6, 138.2, 144.4, 155.4; 19F NMR (470 MHz,
CDCl3): δ ꢀ43.7 (s, SCF3); IR: 3411, 2941, 2857, 1612, 1564, 1476, 1210, 1129, 1099, 1031, 863, 754 cmꢀ1; ESIꢀ
HRMS m/z calcd for C11H10F3OS (M−H)− 247.0410, found 247.0411.
°
1ꢀ(Trifluoromethylthio)ꢀ5,6,7,8ꢀtetrahydronaphthalenꢀ2ꢀol 6cc. White solid; mp 49.3–49.5 C; (1 mmol 5c, 1.3
1
mmol PhNHSCF3, 3 mmol BF3·Et2O); H NMR (500 MHz, CDCl3): δ 1.72–1.85 (m, 4H), 2.69–2.74 (m, 2H),
2.92–2.97 (m, 2H), 6.39 (s, 1H), 6.87 (d, J = 8.4 Hz, 1H), 7.15 (d, J = 8.4 Hz, 1H); 13C NMR (125 MHz, CDCl3):
δ 22.5, 22.9, 28.8, 29.1, 107.8, 113.1, 128.9 (q, J = 311.7 Hz), 130.6, 134.9, 143.2, 156.6; 19F NMR (470 MHz,
CDCl3): δ ꢀ42.2 (s, SCF3); IR: 3422, 2938, 1592, 1579, 1471, 1430, 1303, 1204, 1146, 1128, 1094, 832, 818,
752, 734 cmꢀ1; ESIꢀHRMS m/z calcd for C11H10F3OS (M−H)− 247.0410, found 247.0410.
5ꢀ(Trifluoromethylthio)ꢀ2ꢀ((trifluoromethylthio)methyl)ꢀ2,3ꢀdihydrobenzofuran 9. Yellow, viscous liquid; (1
mmol 7, 2.5 mmol PhNHSCF3, 4 mmol TfOH); 1H NMR (500 MHz, CDCl3): δ 3.08 (dd, J = 16.1, 6.6 Hz, 1H),
3.16 (dd, J = 14.0, 6.3 Hz, 1H), 3.28 (dd, J = 14.0, 6.3 Hz, 1H), 3.46 (dd, J = 16.1, 9.2 Hz, 1H), 5.05–5.13 (m,
1H), 6.82 (d, J = 8.1 Hz, 1H), 7.42–7.47 (m, 2H); 13C NMR (125 MHz, CDCl3): δ 34.2, 81.6, 110.7, 115.2 (d, J
= 1.9 Hz), 127.4, 129.6 (q, J = 308.2 Hz), 130.7 (q, J = 306.4 Hz), 133.6, 137.9, 161.3; 19F NMR (470 MHz,
CDCl3): δ ꢀ41.4 (s, SCF3); ꢀ44.5 (s, SCF3); IR: 1604, 1589, 1474, 1237, 1092, 974, 819, 755 cmꢀ1; Anal Calcd for
C11H8F6OS2: C, 39.52; H: 2.41. Found: C, 39.30; H, 2.34.
°
2ꢀMethoxyꢀ4ꢀmethylꢀ5ꢀ(trifluoromethylthio)phenol 11a. Light yellow solid; mp 51.9–52.1 C; (1 mmol 10a, 1.3
1
mmol PhNHSCF3, 1.3 mmol TfOH); H NMR (500 MHz, CDCl3): δ 2.47 (s, 3H), 3.91 (s, 3H), 5.49 (br s, 1H),
6.79 (s, 1H), 7.21 (s, 1H); 13C NMR (125 MHz, CDCl3): δ 20.8, 55.9, 112.6, 114.4 (q, J = 1.5 Hz), 123.6, 129.8
(q, J = 308.8 Hz), 136.7, 143.8, 148.9; 19F NMR (470 MHz, CDCl3): δ ꢀ43.7 (s, SCF3); IR: 3343, 1580, 1266,
1135, 1100, 1043, 872, 850, 817, 753 cmꢀ1; ESIꢀHRMS m/z calcd for C9H8F3O2S (M−H)− 237.0203, found
237.0200.
°
2,6ꢀDimethoxyꢀ3ꢀ(trifluoromethylthio)phenol 11b. Brown solid; mp 44.7–46.5 C; (1 mmol 10b, 1.3 mmol
PhNHSCF3, 1.3 mmol TfOH); 1H NMR (500 MHz, CDCl3): δ 3.93 (s, 3H), 3.97 (s, 3H), 5.66 (br s, 1H), 6.69 (d,
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J = 8.7 Hz, 1H), 7.16 (d, J = 8.7 Hz, 1H); 13C NMR (125 MHz, CDCl3): δ 56.3, 61.2, 106.7, 109.5 (d, J = 1.8
Hz), 129.0, 129.4 (q, J = 308.7 Hz), 139.2, 148.9, 150.5; 19F NMR (470 MHz, CDCl3): δ ꢀ43.6 (s, SCF3); IR:
3523, 3371, 1594, 1489, 1469, 1439, 1294, 1219, 1083, 892, 796 cmꢀ1; ESIꢀHRMS m/z calcd for C9H8F3O3S
(M−H)− 253.0152, found 253.0151.
°
4ꢀ(Trifluoromethylthio)ꢀ5,6,7,8ꢀtetrahydronaphthalenꢀ1ꢀol 11c. Grey solid; mp 65.2–67.5 C; (1 mmol 10c, 1.3
1
mmol PhNHSCF3, 3 mmol BF3·Et2O); H NMR (500 MHz, CDCl3): δ 1.76–1.86 (m, 4H), 2.61–2.67 (m, 2H),
2.93–2.99 (m, 2H), 5.04 (br s, 1H), 6.66 (d, J = 8.3 Hz, 1H), 7.42 (d, J = 8.3 Hz, 1H); 13C NMR (125 MHz,
CDCl3): δ 22.0, 22.5, 23.2, 28.9, 112.8, 114.7 (q, J = 1.5 Hz), 125.3, 129.8 (q, J = 308.7 Hz), 137.1, 144.7,
156.1; 19F NMR (470 MHz, CDCl3): δ ꢀ43.8 (s, SCF3); IR: 3590, 3461, 1573, 1456, 1440, 1416, 1073, 1029,
819, 805, 750 cmꢀ1; ESIꢀHRMS m/z calcd for C11H10F3OS (M−H)− 247.0410, found 247.0411.
°
4ꢀ(Trifluoromethylthio)naphthalenꢀ1ꢀol 11d. Gray solid; mp 64.8–67.2 C; (1 mmol 10d, 1.3 mmol PhNHSCF3,
1
3 mmol BF3·Et2O); H NMR (300 MHz, CDCl3): δ 6.84 (d, J = 7.9 Hz, 1H), 7.54–7.61 (m, 1H), 7.64–7.71 (m,
1H), 7.82 (d, J = 7.9 Hz, 1H), 8.23 – 8.29 (dd, J = 8.3, 0.5 Hz, 1H), 8.47– 8.53 (m, 1H); 13C NMR (125 MHz,
CDCl3): δ 108.6, 112.5 (q, J = 1.5 Hz), 122.3, 125.1, 125.9, 126.0, 128.2, 129.6 (q, J = 309.5 Hz), 136.7, 138.7,
155.0; 19F NMR (470 MHz, CDCl3): δ ꢀ43.8 (s, SCF3); IR: 3346, 1591, 1569, 1510, 1348, 1158, 1092, 1047,
830, 763, 753 cmꢀ1; ESIꢀHRMS m/z calcd for C11H6F3OS (M−H)− 243.0097, found 243.0096.
°
1ꢀ(Trifluoromethylthio)naphthalenꢀ2ꢀol 11e. Light yellow solid; mp 91.8–92.2 C (lit.56 88.8–90.7 °C); (1 mmol
10e, 1.3 mmol PhNHSCF3, 1.3 mmol TfOH); 1H NMR (300 MHz, CDCl3): δ 6.92 (br s, 1H), 7.30 (d, J = 9.0 Hz,
1H), 7.39–7.47 (m, 1H), 7.58–7.67 (m, 1H), 7.77–7.85 (m, 1H), 7.95 (d, J = 9.0 Hz, 1H), 8.30–8.36 (d, J = 8.4
Hz, 1H); 13C NMR (75 MHz, CDCl3): δ 100.8 (q, J = 0.6 Hz), 117.1, 124.3, 124.4, 128.4, 128.5, 128.8 (q, J =
312.8 Hz), 129.4, 134.9, 135.8, 158.4; 19F NMR (470 MHz, CDCl3): δ ꢀ42.3 (s, SCF3); IR: 3415, 1618, 1591,
1569, 1462, 1384, 1196, 1146, 1125, 1101, 1029, 867, 772, 655 cmꢀ1; ESIꢀHRMS m/z calcd for C11H6F3OS
(M−H)− 243.0097, found 243.0097.
°
1,8ꢀbis(trifluoromethylthio)naphthaleneꢀ2,7ꢀdiol 11f. Light orange solid; mp 90.3–91.4 C; (1 mmol 10f, 2.4
PhNHSCF3, 4.0 mmol TfOH); 1H NMR (500 MHz, CDCl3): δ 7.25 (d, J = 8.8 Hz, 2H), 7.71 (s, 2H), 7.87 (d, J =
8.8 Hz, 2H); 13C NMR (125 MHz, CDCl3): δ 99.9, 115.0, 125.9, 128.5 (q, J = 312.8 Hz), 136.5, 137.2, 161.7; 19
F
NMR (470 MHz, CDCl3): δ ꢀ43.5 (s, SCF3); IR: 3411, 1607, 1514, 1430, 1355, 1155, 1084, 841, 752 cmꢀ1; ESIꢀ
HRMS m/z calcd for C12H5F6O2S2 (M−H)− 358.9641, found 358.9650.
°
1ꢀ(2,6ꢀDihydroxyꢀ3ꢀ(trifluoromethylthio)phenyl)ethanone 11g. Yellow solid; mp 114.7–117.5 C; (1 mmol 10g,
1.3 mmol PhNHSCF3, 1.3 mmol TfOH); 1H NMR (300 MHz, CDCl3): δ 2.77 (s, 3H), 6.60 (d, J = 8.8 Hz, 1H),
7.58 (br s, 1H), 7.61 (d, J = 8.8 Hz, 1H), 13.40 (br s, 1H); 13C NMR (75 MHz, CDCl3): δ 33.5, 98.2 (q, J = 1.5
Hz), 110.0, 111.9, 128.4 (q, J = 311.7 Hz), 144.1, 160.7, 168.1, 204.9; 19F NMR (470 MHz, CDCl3): δ ꢀ44.4 (s,
SCF3); IR: 3343, 1622, 1581, 1472, 1440, 1373, 1245, 1235, 1158, 1120, 1097, 1042, 963, 903, 819, 656 cmꢀ1;
ESIꢀHRMS m/z calcd for C9H6F3O3S (M−H)− 250.9995, found 250.9994.
4ꢀ(Trifluoromethylthio)benzeneꢀ1,2ꢀdiol 11h. White solid; mp 67.8–69.0 °C; (1 mmol 10h, 1.3 mmol
1
PhNHSCF3, 2.0 mmol BF3·Et2O); H NMR (500 MHz, CDCl3): δ 5.60 (br s, 1H), 5.78 (br s, 1H), 6.90 (d, J =
8.2 Hz, 1H), 7.14 (dd, J = 8.2, 1.8 Hz, 1H), 7.18 (d, J = 1.8 Hz, 1H); 13C NMR (125 MHz, CDCl3): δ 115.1 (q, J
= 2.0 Hz), 116.0, 123.3, 129.5 (q, J = 308.2 Hz), 130.5, 143.6, 146.4; 19F NMR (470 MHz, CDCl3): δ ꢀ44.3 (s,
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SCF3); IR: 3533, 3486, 3349, 1593, 1507, 1276, 1245, 1124, 1100, 811, 782 cmꢀ1; ESIꢀHRMS m/z calcd for
C7H4F3O2S (M−H)− 208.9890, found 208.9889.
°
4ꢀMethylꢀ5ꢀ(trifluoromethylthio)benzeneꢀ1,2ꢀdiol 11i. White solid; mp 71.1–71.5 C; (1 mmol 10i, 1.3 mmol
1
PhNHSCF3, 2.0 mmol BF3·Et2O); H NMR (500 MHz, CDCl3): δ 2.42 (s, 1H), 5.25 (br s, 1H), 5.61 (br s, 1H),
6.84 (s, 1H), 7.17 (s, 1H); 13C NMR (125 MHz, CDCl3): δ 20.4, 113.9 (q, J = 1.6 Hz), 117.5, 124.8, 129.8 (q, J =
308.8 Hz), 138.1, 141.3, 146.6; 19F NMR (470 MHz, CDCl3): δ ꢀ43.9 (s, SCF3); IR: 3284, 1593, 1508, 1447,
1272, 1094, 875, 866, 816 cmꢀ1; ESIꢀHRMS m/z calcd for C8H6F3O2S (M−H)− 223.0046, found 223.0045.
4ꢀ(Trifluoromethylthio)benzeneꢀ1,3ꢀdiol 11j. White solid; mp 48.5–49.7 °C; (1 mmol 10j, 1.3 mmol PhNHSCF3,
1
3.0 mmol BF3·Et2O); H NMR (300 MHz, CDCl3): δ 5.16 (br s, 1H), 6.30 (br s, 1H), 6.47 (dd, J = 8.5, 2.7 Hz,
1H), 6.54 (d, J = 2.7 Hz, 1H), 7.43 (d, J = 8.5 Hz, 1H); 13C NMR (125 MHz, CDCl3): δ 99.6 (q, J = 1.1 Hz),
102.9, 109.6, 128.6 (q, J = 310.9 Hz), 139.4, 159.4, 160.8; 19F NMR (470 MHz, CDCl3): δ ꢀ44.5 (s, SCF3); IR:
3645, 3492, 3338, 1592, 1473, 1324, 1134, 1094, 1057, 968, 843, 809 cmꢀ1; ESIꢀHRMS m/z calcd for
C7H4F3O2S (M−H)− 208.9890, found 208.9889.
4ꢀ(Trifluoromethylthio)benzeneꢀ1,2,3ꢀtriol 11k. Brown solid; mp 82.0–84.9 °C; (1 mmol 10k, 1.3 mmol
PhNHSCF3, 2.0 mmol BF3·Et2O); 1H NMR (300 MHz, CDCl3/acetone): δ 6.47 (d, J = 8.6 Hz, 1H), 6.92 (d, J =
8.6 Hz, 1H); 13C NMR (75 MHz, CDCl3/acetone): δ 99.2 (q, J = 1.7 Hz), 108.4, 128.9 (q, J = 310.2 Hz), 129.4,
131.9, 147.0, 148.5; 19F NMR (470 MHz, CDCl3/acetone): δ ꢀ44.3 (s, SCF3); IR: 3507, 3484, 3397, 3218, 1601,
1503, 1460, 1291, 1267, 1090, 1007, 888, 800, 754, 657 cmꢀ1; ESIꢀHRMS m/z calcd for C7H4F3O3S (M−H)−
224.9839, found 224.9838.
°
6ꢀ(Trifluoromethylthio)benzo[d][1,3]dioxolꢀ5ꢀol 13a. Light yellow solid; mp 82.2–82.7 C; (1 mmol 12a, 1.3
1
mmol PhNHSCF3, 1.3 mmol TfOH); H NMR (500 MHz, CDCl3): δ 5.99 (s, 2H), 6.18 (br s, 1H), 6.59 (s, 1H),
6.94 (s, 1H); 13C NMR (75 MHz, CDCl3): δ 97.7, 102.0, 115.0, 128.6 (q, J = 311.5 Hz), 142.0, 152.7, 154.9; 19
F
NMR (470 MHz, CDCl3): δ ꢀ44.5 (s, SCF3); IR: 3433, 1614, 1496, 1470, 1160, 1099, 1030, 930, 871, 830, 754,
713 cmꢀ1; ESIꢀHRMS m/z calcd for C8H4F3O3S (M−H)− 236.9839, found 236.9840.
°
6ꢀHydroxyꢀ5ꢀ(trifluoromethylthio)benzo[d][1,3]oxathiolꢀ2ꢀone 13b. Light yellow solid; mp 128.9–131.7 C; (1
mmol 12b, 1.3 mmol PhNHSCF3, 4.0 mmol TfOH); 1H NMR (500 MHz, Acetoneꢀd6): δ 7.12 (s, 1H), 7.96 (s,
1H), 9.93 (br s, 1H); 13C NMR (125 MHz, Acetone): δ 102.4, 108.6 (q, J = 1.5 Hz), 115.7, 131.5 (q, J = 308.4
Hz), 134.3, 153.7, 161.7, 170.6; 19F NMR (470 MHz, Acetoneꢀd6): δ ꢀ43.0 (s, SCF3); IR: 3416, 1732, 1603,
1454, 1428, 1327, 1145, 1090, 1032, 1013, 881, 865 cmꢀ1; ESIꢀHRMS m/z calcd for C8H2F3O3S2 (M−H)−
266.9403, found 266.9404.
2ꢀIsopropylꢀ5ꢀmethylꢀ4ꢀ(trifluoromethylthio)phenol 13c. Colorless, viscous liquid; (1.0 mmol 12c, 1.3 mmol
1
PhNHSCF3, 2.0 mmol TfOH); H NMR (500 MHz, CDCl3): δ 1.25 (d, J = 6.9 Hz, 6H), 2.44 (s, 3H), 3.14
(septet, J = 6.9 Hz, 1H), 4.95 (br s, 1H), 6.70 (s, 1H), 7.44 (s, 1H); 13C NMR (75 MHz, CDCl3): δ 20.7, 22.4,
26.8, 114.7 (q, J = 1.7 Hz), 117.7, 129.9 (q, J = 308.7 Hz), 133.4, 137.1, 143.1, 155.4; 19F NMR (470 MHz,
CDCl3): δ ꢀ44.0 (s, SCF3); IR: 3422, 1397, 1256, 1152, 1095, 1070, 736 cmꢀ1; ESIꢀHRMS m/z calcd for
C11H12F3OS (M−H)− 249.0566, found 249.0567.
(13S)ꢀ13ꢀMethylꢀ2ꢀ(trifluoromethylthio)ꢀ7,8,9,11,12,13,14,15,16,17ꢀdecahydroꢀ6Hꢀcyclopenta[a]phenanthreneꢀ
°
1
3,17ꢀdiol 13d. White solid; mp 96.1–98.9 C; (0.5 mmol 12d; 0.65 mmol PhNHSCF3, 0.65 mmol TfOH); H
NMR (300 MHz, CDCl3): δ 0.79 (s, 3H), 1.10–1.60 (m, 8H), 1.63–1.77 (m, 1H), 1.83–2.02 (m, 2H), 2.06–2.22
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(m, 2H), 2.24–2.35 (m, 1H), 2.81–2.91 (m, 2H), 3.74 (t, J = 8.4 Hz, 1H), 6.04 (br s, 1H), 6.79 (s, 1H), 7.44 (s,
1H); 13C NMR (125 MHz, CDCl3): δ 11.0, 23.1, 26.2, 26.8, 29.6, 30.5, 36.5, 38.4, 43.2, 43.6, 49.9, 81.8, 105.1
(q, J = 0.9 Hz), 115.8, 128.8 (q, J = 310.6 Hz), 134.1, 135.0, 144.2, 155.6; 19F NMR (470 MHz, CDCl3): δ ꢀ43.7
(s, SCF3); IR: 3318, 2921, 2867, 1560, 1447, 1102, 1055, 1011, 797 cmꢀ1; ESIꢀHRMS m/z calcd for
C19H22F3O2S (M−H)− 371.1298, found 371.1303.
(13S)ꢀ13ꢀMethylꢀ4ꢀ(trifluoromethylthio)ꢀ7,8,9,11,12,13,14,15,16,17ꢀdecahydroꢀ6Hꢀcyclopenta[a]phenanthreneꢀ
°
1
3,17ꢀdiol 13dd. White solid; mp 84.8–87.5 C; (0.5 mmol 12d; 0.65 mmol PhNHSCF3, 0.65 mmol TfOH); H
NMR (500 MHz, CDCl3): δ 0.78 (s, 3H), 1.14–1.22 (m, 1H), 1.23–1.43 (m, 5H), 1.43–1.55 (m, 2H), 1.67–1.76
(m, 1H), 1.92–2.00 (m, 2H), 2.08–2.22 (m, 2H), 2.25–2.33 (m, 1H), 2.84–2.95 (m, 1H), 3.14–3.22 (m, 1H), 3.74
(t, J = 8.5 Hz, 1H), 6.43 (br s, 1H), 6.91 (d, J = 8.6 Hz 1H), 7.40 (d, J = 8.6 Hz 1H); 13C NMR (125 MHz,
CDCl3): δ 11.0, 23.0, 26.4, 27.0, 29.2, 30.6, 36.6, 38.0, 43.2, 44.1, 49.9, 81.8, 108.0, 113.0, 128.9 (q, J = 311.8
Hz), 131.1, 134.0, 143.2, 156.5; 19F NMR (470 MHz, CDCl3): δ ꢀ42.0 (s, SCF3); IR: 3645, 3455, 2938, 2857,
1572, 1352, 1156, 1114, 1098, 1009, 821, 802, 755 cmꢀ1; ESIꢀHRMS m/z calcd for C19H22F3O2S (M−H)−
371.1298, found 371.1307.
(13S)ꢀ3ꢀHydroxyꢀ13ꢀmethylꢀ2ꢀ(trifluoromethylthio)ꢀ7,8,9,11,12,13,15,16ꢀoctahydroꢀ6Hꢀ
cyclopenta[a]phenanthrenꢀ17(14H)ꢀone 13e. White solid; mp 160.4–160.9 °C; (0.5 mmol 12e, 0.65 mmol
1
PhNHSCF3, 0.65 mmol TfOH); H NMR (300 MHz, CDCl3): δ 0.92 (s, 3H), 1.34–1.74 (m, 6H), 1.90–2.30 (m,
5H), 2.34–2.43 (m, 1H), 2.45–2.58 (m, 1H), 2.85– 2.97 (m, 2H), 6.09 (br s, 1H), 6.81 (s, 1H), 7.44 (s, 1H); 13C
NMR (75 MHz, CDCl3): δ 13.8, 21.5, 25.8, 26.2, 29.5, 31.4, 35.8, 37.9, 43.6, 47.9, 50.4, 105.4 (q, J = 1.2 Hz),
115.9, 128.8 (q, J = 310.6 Hz), 133.5, 135.0, 143.9, 155.8, 220.5; 19F NMR (470 MHz, CDCl3): δ ꢀ43.7 (s,
SCF3); IR: 3323, 1723, 1601, 1502, 1410, 1103, 895, 877, 674 cmꢀ1; ESIꢀHRMS m/z calcd for C19H20F3O2S
(M−H)− 369.1142, found 369.1141.
(13S)ꢀ3ꢀHydroxyꢀ13ꢀmethylꢀ4ꢀ(trifluoromethylthio)ꢀ7,8,9,11,12,13,15,16ꢀoctahydroꢀ6Hꢀ
°
cyclopenta[a]phenanthrenꢀ17(14H)ꢀone 13ee. White solid; mp 171.7–172.7 C; (0.5 mmol 12e, 0.65 mmol
1
PhNHSCF3, 0.65 mmol TfOH); H NMR (500 MHz, CDCl3): δ 0.92 (s, 3H), 1.37–1.58 (m, 5H), 1.59–1.70 (m,
1H), 1.93–2.00 (m, 1H), 2.02–2.11 (m, 2H), 2.11–2.20 (m, 1H), 2.21–2.29 (m, 1H), 2.34–2.42 (m, 1H), 2.48–
2.66 (m, 1H), 2.89–3.00 (m, 1H), 3.21–3.28 (m, 1H), 6.44 (br s, 1H), 6.92 (d, J = 8.7 Hz, 1H), 7.40 (d, J = 8.7
Hz, 1H); 13C NMR (125 MHz, CDCl3): δ 13.8, 21.5, 26.0, 26.3, 29.0, 31.5, 35.8, 37.5, 44.1, 47.9, 50.3, 108.0,
113.2, 128.9 (q, J = 311.8 Hz), 131.1, 133.4, 143.0, 156.7, 220.7; 19F NMR (470 MHz, CDCl3): δ ꢀ41.9 (s,
SCF3); IR: 3396, 1732, 1471, 1154, 1118, 1092, 824, 754 cmꢀ1; ESIꢀHRMS m/z calcd for C19H20F3O2S (M−H)−
369.1142, found 369.1143.
°
1
2ꢀNitroꢀ4ꢀ(trifluoromethylthio)phenol 14. Yellow solid; mp 51.6–52.9 C; H NMR (300 MHz, CDCl3): δ 7.25
(d, J = 8.8 Hz, 1H), 7.84 (dd, J = 8.8, 2.2 Hz, 1H), 8.45 (d, J = 2.2 Hz, 1H), 10.77 (s, 1H); 13C NMR (75 MHz,
CDCl3): δ 115.7 (q, J = 2.3 Hz), 121.5, 129.1 (q, J = 308.8 Hz), 133.6, 133.7, 144.8, 156.9; 19F NMR (470 MHz,
CDCl3): δ ꢀ43.7 (s, SCF3); IR: 3256, 1614, 1519, 1474, 1413, 1316, 1243, 1150, 1108, 1088, 1072, 848, 672 cmꢀ
1; ESIꢀHRMS m/z calcd for C7H3F3NO3S (M−H)− 237.9791, found 237.9792.
°
1
2,6ꢀDinitroꢀ4ꢀ(trifluoromethylthio)phenol 15. Yellow solid; decomp., 170 C; H NMR (500 MHz, Acetoneꢀd6):
δ 8.38 (s, 2H); 13C NMR (125 MHz, Acetoneꢀd6): δ 106.8, 131.3 (q, J = 308.0 Hz), 140.1, 143.5, 158.4; 19F
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NMR (470 MHz, Acetoneꢀd6): δ ꢀ44.0 (s, SCF3); IR: 3438, 3091, 1624, 1527, 1338, 1252, 1136, 1090, 913, 776,
724, 683 cmꢀ1; ESIꢀHRMS m/z calcd for C7H2F3N2O5S (M−H)− 282.9642, found 282.9643.
°
1
2,6ꢀDibromoꢀ4ꢀ(trifluoromethylthio)phenol 16. Yellow solid; mp 51.3–53.4 C; H NMR (500 MHz, CDCl3): δ
6.23 (br s, 1H), 7.77 (s, 2H); 13C NMR (125 MHz, CDCl3): δ 110.2, 117.2 (q, J = 2.2 Hz), 129.1 (q, J = 308.9
Hz), 139.7, 152.1; 19F NMR (470 MHz, CDCl3): δ ꢀ43.8 (s, SCF3); IR: 3459, 1452, 1383, 1325, 1159, 1094, 877,
735, 709 cmꢀ1; ESIꢀHRMS m/z calcd for C7H2Br2F3OS (M−H)− 348.8151, found 348.8152.
°
1
2,6ꢀDiiodoꢀ4ꢀ(trifluoromethylthio)phenol 17. Gray solid; mp 86.0–87.6 C; H NMR (300 MHz, CDCl3): δ 6.05
(br s, 1H), 7.97 (s, 2H); 13C NMR (125 MHz, CDCl3): δ 82.2, 118.3 (q, J = 2.0 Hz), 129.1 (q, J = 308.9 Hz),
146.7, 156.1; 19F NMR (470 MHz, CDCl3): δ ꢀ43.8 (s, SCF3); IR: 3439, 1440, 1375, 1302, 1105, 895, 753, 699
cmꢀ1; ESIꢀHRMS m/z calcd for C7H2F3I2OS (M−H)− 444.7873, found 444.7883.
1
(4ꢀPhenoxyphenyl)(trifluoromethyl)sulfane 18. Colorless, viscous liquid; H NMR (300 MHz, CDCl3): δ 6.96–
7.03 (m, 2H), 7.04–7.10 (m, 2H), 7.16–7.23 (m, 1H), 7.35–7.44 (m, 2H), 7.56–7.63 (m, 2H); 13C NMR (125
MHz, CDCl3): δ 117.2 (q, J = 1.9 Hz), 118.6, 120.1, 124.6, 129.5 (q, J = 308.2 Hz), 130.0, 138.3, 155.5, 160.4;
19F NMR (470 MHz, CDCl3): δ ꢀ44.1 (s, SCF3); IR: 1581, 1485, 1240, 1110, 1081, 869, 834, 754, 692 cmꢀ1;
Anal Calcd for C13H9F3OS: C, 57.77; H, 3.36. Found: C, 57.73; H, 3.09.
°
1
(4ꢀ(4ꢀBromobenzyloxy)phenyl)(trifluoromethyl)sulfane 19. Light yellow solid; mp 54.8–55.5 C; H NMR (500
MHz, CDCl3): δ 5.04 (s, 2H), 6.96 – 7.00 (m, 2H), 7.30 (d, J = 8.3 Hz, 2H), 7.53 (d, J = 8.3 Hz, 2H), 7.56 – 7.60
(m, 2H); 13C NMR (125 MHz, CDCl3): δ 69.4, 115.4 (q, J = 1.9 Hz), 115.8, 122.2, 129.1, 129.6 (q, J = 308.2
Hz), 131.8, 135.2, 138.3, 160.7; 19F NMR (470 MHz, CDCl3): δ ꢀ44.3 (s, SCF3); IR: 1590, 1494, 1453, 1411,
1377, 1251, 1107, 1088, 1042, 1012, 831, 809, 799, cmꢀ1; ESIꢀHRMS m/z calcd for C14H9BrF3OS (M−H)−
360.9515, found 360.9522.
°
1
(4ꢀ(Biphenylꢀ4ꢀylmethoxy)phenyl)(trifluoromethyl)sulfane 20. White solid; mp 107.0–108.4 C; H NMR (300
MHz, CDCl3): δ 5.14 (s, 2H), 7.01–7.07 (m, 2H), 7.33–7.41 (m, 1H), 7.42–7.54 (m, 4H), 7.57–7. 67 (m, 6H);
13C NMR (125 MHz, CDCl3): δ 69.9, 115.2 (q, J = 1.9 Hz), 115.8, 127.1, 127.5, 128.0, 128.8, 129.6 (q, J =
308.2 Hz), 135.1, 138.3, 140.6, 141.3, 161.0; 19F NMR (470 MHz, CDCl3): δ ꢀ44.3 (s, SCF3); IR: 1589, 1491,
1380, 1247, 1106, 1083, 1028, 1005, 826, 763, 700 cmꢀ1; ESIꢀHRMS m/z calcd for C20H14F3OS (M−H)−
359.0723, found 359.0720.
Acknowledgement
Mrs. T. Stipanovič and Prof. B. Stanovnik for the elemental combustion analyses, Dr. D.
Urankar and Prof. J. Košmrlj for HRMS, and Ministry of Higher Education, Science and
Technology (P1ꢀ0134) for financial support are gratefully acknowledged.
References
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DOI: 10.1039/C4OB02633K
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