Preparation of polymer-supported selenocyanates and their application to solid-phase oxyselenenylation-deselenenylation

Article abstract of DOI:10.1055/s-1999-2954

Polymer-supported selenocyanates were readily prepared from substituted- polystyrene resins such as Merrifield resin and aminomethyl-polystyrene resin. Employing these polymer-supported selenocyanates, the corresponding oxyselenenylation-deselenenylation reactions proceeded in the solid-phase.

Full text of DOI:10.1055/s-1999-2954

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760
LETTER
Preparation of Polymer-Supported Selenocyanates and their Application to
Solid-Phase Oxyselenenylation-Deselenenylation
Ken-ichi Fujita,* Katsuhiro Watanabe, Akihiro Oishi, Yoshikazu Ikeda, Yoichi Taguchi
National Institute of Materials and Chemical Research, 1-1, Higashi, Tsukuba, Ibaraki 305-8565, Japan
Fax +81-298-54-4511; E-mail: kfujita@nimc.go.jp
Received 28 August 1999
Polymer-supported selenocyanates were prepared accord-
Abstract: Polymer-supported selenocyanates were readily pre-
ing to Scheme 1. Chloromethyl-polystyrene resin 1 (Mer-
pared from substituted-polystyrene resins such as Merrifield resin
rifield resin, 4.3 mmol/g, crosslinked with 2 %
ported selenocyanates, the corresponding oxyselenenylation-dese- divinylbenzene) was treated with potassium selenocyan-
and aminomethyl-polystyrene resin. Employing these polymer-sup-
lenenylation reactions proceeded in the solid-phase.
ate in N,N-dimethylformamide (DMF) at room tempera-
ture for overnight. Formation of polymer-supported
selenocyanate 2 was indicated by IR spectra showing a
strong stretching vibration of the cyano group at 2149
Key words: polymer-supported selenocyanate, solid-phase synthe-
sis
–
1
cm . Elemental analysis of selenium showed that 2 was
6
obtained in nearly quantitative yield. Similarly, Wang
Solid-phase organic synthesis is a powerful and rapid
method for the preparation of large numbers of structural-
bromo resin 3 (1.05 mmol/g, crosslinked with 1 % divi-
nylbenzene), which possessed a phenoxymethyl linker,
also afforded the corresponding polymer-supported sele-
nocyanate 4 in nearly quantitative yield.7
1
ly distinct molecules. In the case of this technique, the
purification of organic molecules has been greatly simpli-
fied through the use of polymer-resins.
In application to solid-phase synthesis, we have examined
The use of organoselenium reagents in organic synthesis
is now commonly accepted as a powerful tool for intro-
ducing new functional groups into organic substrates un-
2
d
an electrophilic oxyselenenylation reaction, which pro-
ceeds exclusively by mechanism of trans-addition. First,
through the addition of bromine to 2 in dichloromethane
2
der extremely mild reaction condition. Among them,
8
to produce the corresponding selenenylbromide, elemen-
selenocyanate is a useful seleno-introducing reagent that
is employed as both an electrophilic and nucleophilic re-
tal selenium was deposited via the decomposition of 2,
contrary to our expectation. Then, stirring 2 and (E)-4-
3
agent. Very recently, Nicolaou et al. have reported the
phenyl-3-butenoic acid in the presence of copper chloride
preparation of polymer-supported selenenyl bromide
from polystyrene resin and its application to organic syn-
9
(
II) in toluene at 80 °C, the corresponding intramolecular
4
oxyselenenylation (namely, selenolactonization) proceed-
ed in the solid-phase to produce polymer-supported sele-
nolactone 5(n=0) (Scheme 1), indicated by a strong
thesis. Herein, we wish to report the very simple prepara-
5
tion of polymer-supported selenocyanates from
substituted-polystyrene resins such as the readily avail-
able Merrifield resin and aminomethyl-polystyrene resin,
and their application as reagents to the oxyselenenylation-
deselenenylation reaction in the solid-phase. A remark-
able advantage of these polymer-supported selenocyan-
ates is their easy handling and odorless nature, as
compared with non-supported selenocyanates, whose tox-
icity and strong odor is often problematic in the laborato-
ry.
–1
carbonyl stretching vibration at 1776 cm in the IR spec-
trum. Moreover, through the oxidation of 5(n=0) with m-
2
d
chloroperbenzoic acid (m-CPBA), the deselenenylation
product 6 was obtained in fair yield (56 % yield from 2).
However in the case of 4, the corresponding solid-phase
selenolactonization by use of copper chloride (II) did not
proceed smoothly to afford a slight amount of 6.
Scheme 1
Synlett 1999, No. 11, 1760–1762 ISSN 0936-5214 © Thieme Stuttgart · New York

LETTER
Preparation of Polymer-Supported Selenocyanates and their Application
1761
Scheme 2
We also prepared polymer-supported arylselenocyanates, References and Notes
whose selenocyano groups are directly attached to the ar-
(
1) (a) Obrecht, D.; Villalgordo, A. M. Solid-Supported
Combinatorial and Parallel Synthesis of Small-Molecular
omatic ring (Scheme 2). Stirring either arylselenocyanate
1
0
7
or 8 and aminomethyl-polystyrene resin (2.0 mmol/g,
crosslinked with 3 % divinylbenzene) in the presence of
-ethyl-1-[3-(dimethylamino)propyl]carbodiimide hy-
drochloride (EDC HCl) and 1-hydroxybenzotriazole
HOBt) in dichloromethane,11 the corresponding poly-
mer-supported arylselenocyanates 9 and 10 were obtained
Weight Compound Libraries; Pergamon Press: Oxford, 1998.
(b) Booth, S.; Hermkens, P. H. H.; Ottenheijm, H. C. J.; Rees,
D. C. Tetrahedron 1998, 54, 15385. (c) Thompson, L. A.;
Ellman, J. A. Chem. Rev. 1996, 96, 555. (d) Fruchtel, J. S.;
Jung, G. Angew. Chem., Int. Ed. Engl. 1996, 35, 17.
3
.
(
(
2) (a) Liotta, D. Ed. Organoselenium Chemistry; Wiley: London,
1
987. (b) Paulmier, C. Ed. Selenium Reagents and
Intermediates in Organic Synthesis; Pergamon Press: Oxford,
986. (c) Reich, H. J. J. Org. Chem., 1974, 39, 428 .
1
2
respectively in nearly quantitative yield. In this type of
polymer-supported selenocyanate, the corresponding se-
lenenyl bromide 11, which acted as an electrophilic re-
agent, was easily prepared by the addition of bromine.
Furthermore, after the removal of excess bromine, the cor-
responding solid-phase selenolactonization of (E)-4-phe-
nyl-3-butenoic acid proceeded in dichloromethane. Also
in this case, subsequent deselenenylation reaction with m-
CPBA proceeded smoothly to provide 6 in decent yield
1
(d) Nicolaou, K. C.; Seitz, S. P.; Sipio, W. J.; Blount, J. F.
J. Am. Chem. Soc. 1979, 101, 3884. (e) Nicolaou, K. C.;
Magolda, R. L.; Sipio, W. J.; Barnette, W. E.; Lysenko, Z.;
Joullie, M. M. J. Am. Chem. Soc., 1980, 102, 3784.
(f) Hayama, T.; Tomoda, S.; Takeuchi, Y.; Nomura, Y.
Tetrahedron Lett., 1982, 23, 4733. (g) Tomoda, S.; Usuki, Y.;
Fujita, K.; Iwaoka, M. Rev. Heteroatom Chem., 1991, 4, 249.
(
h) Fujita, K. J. Syn. Org. Chem., Jpn. 1996, 54, 166.
(
33 % yield from 9, 46 % yield from 10).
(3) (a) Paquette, L. A. Ed. Encyclopedia of Reagents for Organic
Synthesis; John Wiley & Sons: Chichester, 1995; p 4019.
Moreover, in the case of using 10 and 4-pentenoic acid,
the corresponding solid-phase selenolactonization pro-
ceeded smoothly to afford 12 (Scheme 3). However, fol-
lowed by reduction with triphenyltin hydride (Ph SnH),
the corresponding deselenenylation product 13 was ob-
(
1
b) Sevrin, M.; Krief, A. J. Chem. Soc., Chem. Commun.,
980, 656. (c) Tomoda, S.; Takeuchi, Y.; Nomura, Y. Chem.
Lett., 1982, 1733.
1
3
(4) Nicolaou, K. C.; Pastor, J.; Barluenga, S.; Winssinger, N.
Chem. Commun. 1998, 1947.
3
(
5) Previous related report: Michels, R.; Kato, M.; Heitz, W.
Makromol. Chem. 1976, 177, 2311.
tained in low yield probably due to unexpected side-reac-
tion of amide linker with Ph SnH (20 % yield from 10).
3
(
6) 2: pale yellow beads; IR (KBr): 3025, 2922, 2149, 1707, 1510,
–
1
We are currently trying to apply this method to other reac-
tions and to the asymmetric version. The results will be re-
ported in due course.
1451, 1422, 1190, 700, 596 cm ; Anal Calcd: C, 64.17; H,
5.05; N, 4.63; Se, 26.14 %. Found: C, 64.19; H, 4.96; N, 4.01;
Se, 24.21 %.
(
(
7) 4: pale yellow beads; IR (KBr): 3027, 2924, 2149, 1605, 1510,
–
1
1
1
248, 1175, 1017, 758 cm ; Anal Calcd: C, 82.16; H, 6.69; N,
.43; Se, 8.08 %. Found: C, 81.51; H, 6.83; N, 1.30; Se, 7.74
%.
8) Behaghel, O.; Seibert, H. Ber. 1933, 66, 708.
Scheme 3
Synlett 1999, No. 11, 1760–1762 ISSN 0936-5214 © Thieme Stuttgart · New York

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K.-i. Fujita et al.
LETTER
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1
(
9) Toshimitsu, A.; Aoai, T.; Uemura, S.; Okano, M. J. Org.
Chem. 1980, 45, 1953.
10) 7 and 8 were prepared from the corresponding amino
1605, 1510, 1248, 1175, 1017, 758 cm ; Anal Calcd: C,
77.14; H, 6.47; N, 3.73; Se, 10.52 %. Found: C, 76.52; H,
6.68; N, 3.32; Se, 9.05 %.
(
derivatives by diazotization followed by reaction with
potassium selenocyanate.
(13) Clive, D. L. J.; Chittattu, G, J.; Farina, V.; Kiel, W. A.;
Menchen, S. M.; Russell, C. G.; Singh, A.; Wong, C. K.;
Curtis, N. J. J. Am. Chem. Soc. 1980, 102, 4438.
(
(
11) Carpino, L. A. J. Am. Chem. Soc. 1993, 115, 4397.
12) 9: pale yellow beads; IR (KBr): 3025, 2920, 2155, 1649, 1491,
–
1
1
3
1
451, 1296, 754, 698 cm ; Anal Calcd: C, 76.64; H, 6.00; N,
.95; Se, 11.14 %. Found: C, 75.46; H, 6.11; N, 4.02; Se,
0.61 %. 10: pale yellow beads; IR (KBr): 3025, 2922, 2149,
Article Identifier:
1437-2096,E;1999,0,11,1760,1762,ftx,en;Y16899ST.pdf
Synlett 1999, No. 11, 1760–1762 ISSN 0936-5214 © Thieme Stuttgart · New York