LETTER
1913
Polystyrene-Supported Selenosulfonates: Efficient Reagents for Regio- and
Stereocontrolled Synthesis of Vinyl Sulfones
P
olystyrene-Suppo
a
rted
S
eleno
o
sulfonates Qian,a Xian Huang*a,b
a
Department of Chemistry, Zhejiang University (Campus Xixi), Hangzhou 310028, P. R. China
b
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences,
Shanghai 200032, P. R. China
Fax +86(571)88807077; E-mail: huangx @mail.hz.zj.cn
Received 17 September 2001
SOCl2
Abstract: Two novel polystyrene-supported selenosulfonates re-
agents have been developed. As reagents for boron trifluoride cata-
lyzed or AIBN catalyzed addition to olefins were successfully
demonstrated and have been used for regioselective synthesis of vi-
nyl sulfones.
SeCl
2
SeCH3
1
ArSO2Na
ArSO2Na
Key words: solid-phase synthesis, selenosulfonate, polymer re-
agent, vinyl sulfone
SeBr
4
SeSO2Ar
3
3a Ar = Ph
3b Ar =
CH3
= polystyrene
Solid-phase reactions play an important role in parallel
synthesis and combinatorial chemistry, particularly in the
area of medicinal chemistry, where their potential has
emerged as a result of the possibility of automation.1 Vi-
nyl sulfones ( , -unsaturated sulfones) have now become
generally accepted useful intermediates in organic synthe-
sis. Thus vinyl sulfones serve efficiently as both Michael
acceptors and partners in cycloaddition reaction.
Scheme 1
nate or sodium toluenesulfinate in DMF at room tempera-
ture to afford resin 3 (elemental analysis S, 1.12 mmol/g).6
Resin 3 can also been prepared by reaction of resin 4 (el-
emental analysis Br, 1.71 mmol/g)4 with sodium benzene-
sulfinate or sodium toluenesulfinate in DMF at room
temperature (elemental analysis S, 1.33 mmol/g).
Back and co-workers reported3 that the selenosulfonation
of unsymmetrical olefins catalyzed by boron trifluoride
evidently results chiefly or exclusively in Markovnikov
addition. We first examined the selenosulfonation of ole-
fins by the resin 3 in the presence of the boron trifluoride
at room temperature (Scheme 2). Thus the resin 3, cyclo-
hexene and a catalytic amount of boron trifluoride ether-
ate were stirred at room temperature for 40 h, then the
mixture was filtered. The obtained resin 6 may be convert-
ed to 1-p-toluenesulfonylcyclohexene by hydrogen perox-
ide in good yield.7 Results are shown in Table 1.
Many methods for preparing vinyl sulfones have been de-
veloped.2 Among these methods the method for ionic and
radical addition of selenosulfonate to alkenes and alkynes
is more important.3 This convenient method can introduce
two synthetically versatile functionalities, sulfone and se-
lenide, into a given unsaturated substrate in one step. Or-
ganoselenium reagents, however, typically have a foul
smell and are quite toxic, which is often problematic in or-
ganic synthesis.
Our research group has been interested in the application
of organo- selenium reagents in the organic synthesis for
many years. Now we wish to report the preparation of
polystyrene-supported selenosufonates and their applica-
tion for regio and stereocontrolled synthesis of vinyl sul-
fones. A distinct advantage of the new polymer reagents
is the convenience of handling and odorless nature as
compared to the non-polymer-supported reagents. The
preparation of the polystyrene-supported benzeneselenos-
ulfonate and tolueneseleno-sulfonate is described in
Scheme 1.
R1
H
R2
H
BF3 Et2O
r.t.
Se
R1
R2
+
SeSO2Ar
3
SO2Ar
5
6
H2O2
R2
Ar = Ph,
CH3
R1
H
SO2Ar
Resin 1, prepared by literature route,4 reacted with thio-
nylchloride to give resin 2 (elemental analysis Cl, 1.8
mmol/g),5 which was treated with sodium benzenesulfi-
7
Scheme 2
In contrast to the selenosulfonation of olefins by ionic ad-
dition, radical additions of resin 3 to olefins performed by
AIBN catalyasis led to the highly regioselective formation
Synlett 2001, No. 12, 30 11 2001. Article Identifier:
1437-2096,E;2001,0,12,1913,1916,ftx,en;Y19101ST.pdf.
© Georg Thieme Verlag Stuttgart · New York
ISSN 0936-5214