Thiolysis of Alkyl- and Aryl-1,2-epoxides in Water Catalyzed by InCl3

Article abstract of DOI:10.1002/1615-4169(200206)344:3/4<379::AID-ADSC379>3.0.CO;2-4

The pH dependence of thiolysis of 1,2-epoxides with thiophenol in water and the influence of a Lewis acid catalyst is investigated. InCl₃ showed a very high efficiency in catalyzing this process at pH 4.0. The regioselectivity of the nucleophilic attack is markedly influenced going from pH 9.0 to pH 4.0. A one-pot procedure running solely in water to prepare trans-2-(phenylsulphinyl)cyclohexan-1-ol is reported starting from epoxycyclohexane, via thiolysis reaction and oxidation with t-butyl hydroperoxide.

Full text of DOI:10.1002/1615-4169(200206)344:3/4<379::AID-ADSC379>3.0.CO;2-4

FULL PAPERS
Thiolysis of Alkyl- and Aryl-1,2-epoxides in Water Catalyzed by
InCl3
Francesco Fringuelli,* Ferdinando Pizzo, Simone Tortoioli, Luigi Vaccaro
¡
Dipartimento di Chimica, Universita di Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy
Fax: ( ‡ 39)-075-5855560, e-mail: frifra@unipg.it
Received: October 31, 2001; Accepted: February 14, 2002
Abstract: The pH dependence of thiolysis of 1,2- prepare trans-2-(phenylsulphinyl)cyclohexan-1-ol is
epoxides with thiophenol in water and the influence reported starting from epoxycyclohexane, via thiolysis
of a Lewis acid catalyst is investigated. InCl3 showed a reaction and oxidation with t-butyl hydroperoxide.
very high efficiency in catalyzing this process at
pH 4.0. The regioselectivity of the nucleophilic attack
is markedly influenced going from pH 9.0 to pH 4.0. Keywords: green chemistry; InCl3; Lewis acid catal-
A one-pot procedure running solely in water to ysis; thiolysis of oxiranes; water
Introduction
meets ™Click Chemistry∫ standards as described by
Sharpless.[11] The use of water as reaction medium
Ring opening of 1,2-epoxides with thiol-derived nucle- facilitates[12] the nucleophilic addition to epoxides
ophiles is a well-established route to b-hydroxy sulfides because (i) it responds to the demand for hydrogen
that has been applied for the preparation of allylic bonding of these substrates, (ii) its high heat capacity is a
alcohols,[1] cyclic sulfides,[2] thioketones[3] and of impor- helpful property for processes scaling-up, and (iii)
tant intermediates for the synthesis of natural products[4] allows the pH to be easily changed and controlled as
and compounds of biological and pharmacological well as the concentration of aqua ion when the process is
interest.[5]
catalyzed by a Lewis acid. Recently, we have shown[10a f]
To date, the thiolysis of 1,2-epoxides has been that the Lewis acid catalysis in water is strongly depend-
performed fundamentally in two ways: by using thio- ent on the pH and by maintaining the pH at a suitable
lates under basic conditions[6,7] or thiols in the presence level it is possible to either control the regioselectivity of
of a variety of activating agents.[9] In the first case, the the reaction or use Lewis acids such as AlCl3, TiCl4 and
reactions occur with good yields in short times under SnCl4 for which anhydrous conditions are recommend-
anhydrous conditions. The second strategy uses differ- ed. The thiolysis of 1,2-epoxides catalyzed by Lewis
ent kinds of promoting agents including alumina,[9a] acids in water as the only solvent and the dependence of
silica gel,[9b] Montmorillonite,[9c] polyethylene glycol,[9d] this reaction on the pH[13] were not previously inves-
and hydrosulfide exchange resin[9e] as heterogeneous tigated.
catalysts, or the more common Lewis acids such as
LnCl3,[9f] CoCl2,[9g] Ti(O-i-Pr)4,[9h, i] (NH4)2Ce(NO3)6,[9j]
LiClO4,[9k] BF3 ¥ Et2O,[9l] SmI2,[9m] and more complex Results and Discussion
Lewis acids such as (salen)chromium[9n] and titanium
complexes,[9o] tricarbonyl(arene)(thiol)chromium com- First, we investigated the thiolysis of epoxycyclohexane
plex,[9p] gallium binaphthoxide complex[9q] and metal (1) with thiophenol in water at different pH values and
tartrates[9r] to carry out enantioselective syntheses. with various Lewis acid salts. The reactions were
Generally in these cases, the reaction times are long performed under heterogeneous conditions at 30 8C in
and the yields are not always good.
the presence of 10 mol % of catalyst. The pH of the
Our continuing interest in organic synthesis per- reaction medium was kept constant for the entire
formed exclusively in water[10] stimulated us to inves- reaction time.[14] Reactions in the absence of salt catalyst
tigate the Lewis acid-catalyzed thiolysis of epoxides in at the same pH were carried out for comparison
aqueous medium.
purposes. Table 1 illustrates the results. trans-2-(Thio-
This is a part of a synthetic strategy that we have phenyl)cyclohexan-1-ol (2) and trans-1,2-cyclohexane-
developed in the azidolysis,[10a] bromolysis,[10b] and diol (3) were the sole reaction products.
iodolysis[10b] in water of alkyl- and aryl-substituted 1,2-
In the absence of Lewis acid catalysts (Table 1,
epoxides and of a,b-epoxycarboxylic acids and that entries 1, 3, 8, 10) the best result (100% of 2 after 3 h)
Adv. Synth. Catal. 2002, 344, No. 3+4
¹ VCH Verlagsgesellschaft mbH, 69451 Weinheim, Germany, 2002 1615-4150/02/3443+4-379 384 $ 17.50+.50/0
379

Francesco Fringuelli et al.
FULL PAPERS
Table 1. Thiolysis by thiophenol of epoxycyclohexane (1) in
water at 30 8C.
Table 2. Thiolysis by thiophenol of 1,2-epoxides 4 10 in
water at 30 8C.
OH
OH
Epoxide
pH
Cat.
t
C[a] α/β[b] Yield[c]
PhSH
O
+
[10 mol %] [min]
[%]
[%]
90
30
55
91
85
SPh
OH
1
2
3
α
9.0
4.0
4.0
none
none
InCl3
120
120
3
99
3/97
O
Entry pH Catalyst
[10 mol %]
t [min] C[a] [%] Products [%][b]
99d 55/45
β
99
55/45
4
2
3
1
2
3
4
5
6
7
2.0 none
2.0 InCl3
4.0 none
4.0 InCl3
15
3
1440
10
240
420
240
99
99
90
99
99
33
37
25
100
94
100
32
75
0
9.0
4.0
4.0
none
none
InCl3
20
720
5
90
99
99
75/25
70/30
97/3
O
α
β
Ph
6
0
5
4.0 Cu(NO3)2
4.0 Sc(OTf)3
4.0 AlCl3
68
27
25
73
75
9.0
4.0
4.0
none
none
InCl3
120
2160
10
90
19
99
2/98
5/95
O
α
β
β
C6H13
87.0 none
0
4895
100
0
13/87 75[e]
6
7
9
10
11
7.0 InCl3
9.0 none
9.0 InCl3
45
180
120
99
99
99
100
100
100
0
0
0
O
9.0
4.0
4.0
none
none
InCl3
120
2160
10
98
60
99
5/95
88
α
30/70
39/61 50[e]
C5H11
[a]
[b]
Reaction conversion.
GC ratios of the products; when the conversion is
quantitative and 2 was the sole reaction product, it was
isolated with 93 95% yield.
O
9.0
4.0
4.0
none
none
InCl3
2880
1440
10
93
98
99
1/99
63/37
65/35
80
50
95
78
60
50
β
α
C4H9
8
O
was achieved, as expected, under basic conditions
(pH 9.0), namely, when a high concentration of phenyl-
thiolate was present (pKa of PhSH ˆ 6.5).[15]
β
9.0
4.0
4.0
none
none
InCl3
20
1440
5
99
99
99
1/99
82/18
88/12
α
9
At pH 2.0, there was a considerable Br˘nsted catalysis
(Table 1, compare the results of entry 1 and entry 8) but
the reaction was not chemoselective and the diol 3 was
the prevailing compound. At pH 2.0 (Table 1, entry 2)
the InCl3-catalyzed reaction was complete after 3 min,
and the absence of diol 3 (Table 1, compare entry 1 with
2) should indicate that the indium ion coordinates both
the epoxide and the nucleophile which is then delivered
to the oxirane carbon. Under these last conditions a
contribution of Br˘nsted catalysis to the formation of 2
cannot be excluded.
O
β
9.0
4.0
4.0
none
none
InCl3
1440
1440
5
87
13
99
18/82
34/66
40/60
α
10
[a]
[b]
[c]
[d]
[e]
Reaction conversion.
GC ratios of the products.
Yield of the isolated main reaction product.
30% of diol 3 was present.
The a-adduct was characterized by using a chromatogra-
At pH 4.0 InCl3 is the best catalyst with respect to
Cu(NO3)2, Sc(OTf)3, and AlCl3 (Table 1, entries 4 7),
and in this case the proton catalysis is negligible
(Table 1, compare entries 3 and 4).
phically enriched mixture.
reported procedure[16] and the structures of the products
At pH 7.0 (Table 1, entries 8and 9) InCl is able to of thiolysis were proven by H and 13C NMR analyses
1
3
catalyze the reaction too, although less efficiently, while and comparison with authentic samples.[8a,9g,17] The
it is practically ineffective under more basic conditions hydroxy sulfides from the attack of C-a of 6 and 7 and
(Table 1, entries 10 and 11).
the two sulfide regioisomers resulting from the thiolysis
The investigation was then extended to a variety of of 8 are new compounds and are described in the
unsymmetrical 1,2-epoxides to evaluate the regioselec- experimental section. All reactions were performed
tivity of the reaction. Table 2 illustrates the results of the under heterogeneous conditions. The sole formation of
reactions carried out at 308 and at pH 4.0 in the presence trans-b-hydroxy sulfides from thiolysis of 4 indicates
of 10 mol % of InCl3 and at pH 4.0 and 9.0 in the absence that the reaction is anti diastereoselective. The exper-
of catalyst. The epoxides were prepared by epoxidation imental procedure has been found to be efficacious even
of the corresponding alkenes with MCPBA in pH- on a large scale. The reaction under catalyzed acidic
controlled aqueous medium according to our previously conditions of 5 and the reaction under uncatalyzed basic
380
Adv. Synth. Catal. 2002, 344, 379 384

Thiolysis of Alkyl- and Aryl-1,2-epoxides in Water Catalyzed by InCl3
FULL PAPERS
conditions of 6 have been performed on a 100 mmol in water as the only solvent is strongly affected by the pH
scale without encountering any problems and obtaining and by the presence of Lewis acids. Under basic
the same results than those reported for the 1 mmol conditions (pH 9.0) and without catalyst, the reaction
scale.
is generally slow (up to 48h) and occurs prevalently
The uncatalyzed reaction at pH 9.0 proceeds via an (82 99%) at the less substituted b-carbon of unsym-
SN2 mechanism mainly or exclusively at the less metrical epoxides, except when the substituent is a
substituted b-carbon of all the epoxides with the phenyl group (25%). At pH 4.0 and in the presence of
exception of styrene oxide 5, in which the attack of the 10 mol % of InCl3, the reaction is very fast (3 10 min)
nucleophile is driven predominantly, as expected, at the and a higher amount of a-adduct is observed (13 97%).
benzylic a-carbon by electronic effects. At pH 4.0, in the
These results open the route to the synthesis of
absence of InCl3 the a-regioselectivity of the reaction building blocks of synthetic interest such as allylic
strongly increased and in some cases the b-hydroxy-a- alcohols and ketones (either racemic or enantiopure) by
thiophenyl sulfide was the prevalent product (com- an environmentally benign procedure. Moreover, this is
pounds 4, 8, and 9), but long reaction times (2 À 36 h) a rare case[10e, 21] in which the reaction of a monodentate
were generally required. The presence of 10 mol % of substrate is catalyzed in water alone by a Lewis acid.
InCl3 strongly accelerated the reactions that were
completed within 3 À 10 min and likewise greatly
changed the regioisomeric ratio as compared to the
reactions carried out at pH 9.0. Thus, the a-regioselec-
Experimental Section
tivity of thiolysis of 4, 8, and 9 increased by 40, 186, and
733 times and that of the other epoxides by 3 12 times.
The rationalization of the strong catalytic effect of
InCl3 and the increased a-regioselectivity requires
General Remarks
All chemicals were purchased and used without any further
purification. GC analyses were performed with an SPB-5 fused
silica capillary column (30 m, 0.25 mm diameter) an ™on
column∫ injector system, a FID detector, and hydrogen as
the carrier gas. GC/MS analyses were carried out with 70 eV
electron energy. Column chromatographies were performed
on silica gel (0.040 0.062 mm). 1H and 13C NMR spectra were
recorded at 200, 101.2, 50.6 MHz respectively, in CDCl3 as
solvent with TMS as internal standard. Epoxides 1, 5, and 6 are
commercially available, epoxides 4, 7, 8, 9, and 10 were
synthesized by oxidation of the corresponding alkene with m-
chloroperoxybenzoic acid (MCPBA).[16] In a typical procedure
MCPBA (77%; 22 mmol) was added to an aqueous suspension
of the alkene (20 mmol) in 130 mL of 0.3 N aqueous NaHCO3
at 0 8C over 10 min. The heterogeneous mixture was stirred for
further investigations. At present, these results can be
3‡
justified considering that the aqua species In(H2O)6
,
present in high concentration at pH 4.0,[18] coordinates
to the epoxide resulting in a considerable positive
charge on the more substituted a-carbon, thereby
favoring the nucleophilic attack according to an SN2-
borderline mechanism.
The metal-complexation of epoxide probably causes a
greater polarization of more substituted a-carbon of
oxirane than that produced by protonation. The regio-
selectivities of the ring-opening observed in the proton-
and indium-catalyzed reactions are roughly the same,
indicating that the charge density ratio on C-a and C-b
of protonated epoxide is very similar to that of indium-
complexed epoxide.
Several years ago, we reported that sulfoxides can be
easily prepared with excellent yields by oxidation of
sulfides with t-butyl hydroperoxide in water under acidic
conditions.[19] Coupling that procedure with the thiolysis
reported here, b-hydroxyphenyl sulfoxides can be
prepared from epoxides by a one-pot procedure[20] in
aqueous medium. For example, the trans-2-(phenyl-
sulfinyl)-cyclohexane-1-ol was obtained as a 7:3 mixture
of two sulfoxide diasteroisomers[1a] from epoxycyclo-
hexane (1) in quantitative yield. The procedure does not
require any organic co-solvent since the sulfoxides
precipitated from the aqueous medium and were
isolated by simple filtration.
2
4 h and then extracted with Et2O (4 Â 40 mL); the organic
phase was washed two times with a cold 1.5 M aqueous solution
of NaOH, dried (Na2SO4) and concentrated under reduced
pressure furnishing the epoxide in 80 90% yield. The hydroxy
sulfides arising from thiolysis of 1,[9a,17b] 4,[17a,17b] 5,[17b,9g] 9,[17c,17d]
10,[17e,17f] and those coming from the attack at C-b of 6,[8a] 7,[17g]
are known compounds.
The hydroxy sulfides from the attack at C-a of 6 and 7 and
the two sulfides regioisomers resulting from the thiolysis of 8
are new compounds.
Thiolysis of 1,2-Epoxides in the Absence of InCl3
In a flask thermostatted at 30 8C, equipped with a magnetic
stirrer and pH-stat apparatus, thiophenol (0.15 mL, 1.5 mmol)
was dissolved in water (2.0 mL). The resulting pH was 4.5. By
adding some drops of a concentrated aqueous solution of
H2SO4 or NaOH the pH was adjusted at the desired value. The
epoxide (1.0 mmol) was added under stirring and the pH was
kept constant at the fixed value by adding a 10% aqueous
H2SO4 solution. After the times reported in Tables some drops
of concentrated NaOH solution were added and the mixture
Conclusion
In summary, the reactivity and regioselectivity of
thiolysis of alkyl- and aryl-1,2-epoxides with thiophenol was extracted with Et2O (3 Â 2 mL). The combined organic
Adv. Synth. Catal. 2002, 344, 379 384
381

Francesco Fringuelli et al.
FULL PAPERS
1
layers were dried and evaporated under reduced pressure to
give the b-hydroxy sulfide which was purified by column
chromatography.
(s) cmÀ1; H NMR (200 MHz, CDCl3): d ˆ 0.87 (t, J ˆ 6.9 Hz,
3H, H-7), 1.23 (s, 3H, Me), 1.26 (s, 3H, Me), 1.3 1.5 (m, 6H, H-
4, -5, -6), 2.70 (br s, 1H, OH), 3.03 (dd, J ˆ 10.9, 1.9 Hz, 1H, H-
3), 7.14
7.3 (m, 3H, H-aromatic), 7.4
7.5 (m, 2H, H-
aromatic); 13C NMR (50.6 MHz, CDCl3): d ˆ 13.9, 22.5, 25.9,
27.1, 30.5, 32.3, 65.4, 73.1, 126.4, 128.9, 130.7, 137.4; MS (EI,
‡
Thiolysis of 1,2-Epoxides in the Presence of InCl3 at
pH 4.0
70 eV): m/z ˆ 238(M , 11), 180 (83), 123 (41), 110 (100), 59
(46), 43 (26); anal. calcd. for C14H22OS (238.14): C 70.54, H 9.30,
S 13.45%; found: C 70.49, H 9.28, S 13.37%.
In a flask thermostatted at 30 8C, equipped with a magnetic
stirrer and pH-stat apparatus, thiophenol (0.15 mL, 1.5 mmol)
and 1.0 mL of a 0.1 M aqueous solution of the InCl3 (0.1 mmol)
were added to 0.7 mL of water. The resulting pH was 1.8. By
addition of 100 mL of an aqueous 0.5 M solution of NaOH the
pH was brought at 4.0. The epoxide (1.0 mmol) was then added
under stirring and the pH was kept constant at the fixed value
by adding a 10% aqueous H2SO4 solution. After the times
reported in Tables the reaction mixture was worked-up as
above.
Scale-Up of Thiolysis of Epoxides 5 and 6
The thiolysis under catalyzed acidic conditions of 5 and that
under uncatalyzed basic conditions of 6 have been performed
on a 100 mmol scale following the above described exper-
imental procedures and obtaining the same yields and selec-
tivities reported in Table 2 but with longer reaction times
(10 min and 4 h, respectively).
2-(Thiophenyl)octan-1-ol: Prepared under acidic conditions
(pH ˆ 4.0, InCl3) from 6. The chromatographic purification of
this product is difficult because it is present at 13% in the
reaction mixture. It is identified by using an enriched mixture
obtained by column chromatography on silica gel eluting with
95/5, n-hexane/EtOAc; yield: see Table 2. 1H NMR (200 MHz,
CDCl3): d ˆ 0.87 (t, J ˆ 6.4 Hz, 3H, H-8), 1.27 1.54 (m, 10H,
H-3, -4, -5, -6, -7), 1.87 (br s, 1H, OH), 3.13 3.17 (m, 1H, H-2),
3.52 (dd, J ˆ 11.5, 6.3 Hz, 1H, H-1a), 3.62, (dd, J ˆ 11.5, 5.0 Hz,
1H, H-1b), 7.19 7.41 (m, 5H, H-aromatic); 13C NMR
(101.2 MHz, CDCl3): d ˆ 14.0, 22.5, 26.9, 29.1, 31.2, 31.6, 52.5,
63.8, 127.3, 128.9, 132.7, 133.7.
One-Pot Synthesis of trans-2-(Phenylsulfinyl)-
cyclohexan-1-ol
In a flask thermostatted at 30 8C, equipped with a magnetic
stirrer and pH-stat apparatus, thiophenol (0.3 mL, 3.0 mmol)
and 2.0 mL of aqueous 0.1 M InCl3 (0.2 mmol) were dissolved
in 2.0 mL of water. The resulting pH value was 1.8. By the
addition of 100 mL of an aqueous 5 M solution of NaOH the pH
was adjusted at 4.0. Epoxide 1 (0.2 mL, 2.0 mmol) was added.
During the reaction the pH was kept constant by adding a 10%
aqueous solution of H2SO4. After 10 min 70% aqueous
solution of t-butyl hydroperoxide (1.5 mL, 12 mmol) was
added, the pH adjusted to 4.0 and the resulting mixture heated
at 70 8C for 4 hours. The mixture was cooled to room temper-
ature and filtered to give the hydroxy sulfoxides in quantitative
yield as a mixture of two diastereoisomers: major isomer
(70%): 1H NMR (CDCl3, 200 MHz): d ˆ 0.90 1.53 (m, 6H, H-
3, -4,
-5), 1.56 1.82 (br m, 2H, H-1), 2.70 2.83 (ddd, J ˆ 4.4, 9.7,
11.9 Hz, 1H, H-2), 4.06 (m, 1H, H-1), 7.49 7.55 (m, 3H, H-
aromatic), 7.67 7.72 (m, 2H, H-aromatic); minor isomer
(30%): 1H NMR (CDCl3, 200 MHz): d ˆ 0.90 1.53 (m, 6H, H-
3, -4, -5), 2.03 2.20 (br m, 2H, H-1), 2.60 (dd, J ˆ 15.7, 10.0 Hz,
1H, H-2), 3.92 (m, 1H, H-1), 7.49 7.55 (m, 3H, H-aromatic),
7.67 7.72 (m, 2H, H-aromatic).
2-Methyl-2-(thiophenyl)-heptan-1-ol: Prepared under acid-
ic conditions (pH ˆ 4.0, InCl3) from 7. It is identified by using
an enriched mixture obtained by chromatography on silica gel
and purified by chromatography on silica gel, eluting with 95/5
petroleum ether/ Et2O: oil; yield: see Table 2. 1H NMR (CDCl3,
200 MHz) d ˆ 0.86 0.93 (t, J ˆ 6.8Hz, 3H, H-7), 1.14 (s, 3H,
Me), 1.20 1.55 (m, 8H, H-3, -4, -5, -6), 2.20 (s, 1H, OH), 3.20
3.25 (m, 2H, H-1), 7.26 7.39 (m, 3H, H-aromatic), 7.46 7.51
(m, 2H, H-aromatic); 13C NMR (CDCl3, 50.6 MHz): d ˆ 14.0,
22.1, 22.6, 23.5, 36.9, 55.8, 66.9, 67.9, 126.2, 128.9, 129.1, 130.2;
‡
MS (EI, 70 eV): m/z ˆ 238(M , 2), 218(90), 185 (17), 154 (20),
109 (100), 65 (45); anal. calcd. for C14H22OS (238.14): C 70.54,
H 9.30, S 13.45%; found: C 70.48, H 9.29 S 13.51%.
2-Methyl-2-(thiophenyl)-heptan-3-ol: Prepared under acid-
ic conditions (pH ˆ 4.0, InCl3) from 8 and purified by column
chromatography on silica gel eluting with 95/5, n-hexane/
EtOAc: oil; yield: 50%. IR (CHCl3): n ˆ 3488 (w), 3067 (w),
2961 (s), 1462 (m), 1390 (m), 1304 (m), 1272 (m), 1057 (w) cmÀ1;
1H NMR (200 MHz, CDCl3): d ˆ 0.90 (t, J ˆ 6.9 Hz, 3H, H-7),
1.21 (s, 3H, Me), 1.26 (s, 3H, Me), 1.3 1.6 (m, 6H, H-4, -5, -6),
2.97 (s, 1H, OH), 3.28(d, J ˆ 8.6 Hz, 1H, H-3), 7.2 7.4 (m, 3H,
Acknowledgements
¡
The Ministero dell×Universita e della Ricerca Scientifica e
Tecnologica (MURST), the Consiglio Nazionale delle Ricerche
H-aromatic), 7.5
7.6 (m, 2H, H-aromatic); 13C NMR
¡
(CNR) and the Universita di Perugia are thanked for financial
(50.6 MHz, CDCl3): d ˆ 14.1, 22.0, 22.8, 25.9, 29.5, 30.2, 55.7,
support. The Consorzio Interuniversitario Nazionale Metodo-
logie e Processi Innovativi di Sintesi (CINMPIS) is thanked for
scholarship accorded to Dr. Simone Tortoioli.
‡
75.1, 128.7, 129.1, 130.5, 137.4; MS (EI, 70 eV): m/z ˆ 238(M ,
9), 151 (100), 110 (89), 69 (26), 43 (12); anal. calcd. for C14H22OS
(238.14): C 70.54, H, 9.30, S 13.45%; found: C 70.58, H 9.36, S
13.35%.
2-Methyl-3-(thiophenyl)-heptan-2-ol: Prepared under acid-
ic conditions (pH ˆ 4.0, InCl3) from 8 and purified by column
chromatography on silica gel eluting with 95/5, n-hexane/
EtOAc: oil; yield: 80%. IR (CHCl3): n ˆ 3497 (w), 2929 (s),
1467 (m), 1373 (m), 1337 (m), 1256 (m), 1166 (w), 1114 (s), 1093
References and Notes
¬
¬
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382
Adv. Synth. Catal. 2002, 344, 379 384

Thiolysis of Alkyl- and Aryl-1,2-epoxides in Water Catalyzed by InCl3
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