[CpRu(IV)(p-C3H5)(2-quinolinecarboxylato)]PF6 Complex
UPDATES
ringbar. The whole system was evacuated and filled with argon
gas, and then acetone (150 mL) was introduced, resulting in a
pale yellow solution. To this, a solution of 2-quinolinecarboxyl-
ic acid (1.30 g, 7.56 mmol) in acetone (50 mL), prepared in a
similar way, was introduced through a cannula with a slightly
positive argon pressure. After stirring for 30 min at 278C, a sol-
ution of 2-propen-1-ol (520 mL, 7.56 mmol) in acetone (25 mL)
was introduced to the resultingdark reddish solution through a
cannula, and the mixture was stirred for 15 min at 278C. During
this period, the color faded to yellow. The whole mixture was
concentrated to ca. 30 mL, leadingto precipitation of a pale
yellow solid. The supernatant was removed through a cannula,
one end of which was capped by filter paper. The pale yellow
solid remainingin the Schlenk was washed three times with
cold acetone (total 20 mL, 08C) in the same way. Dryingat
0.005 mmHgfor 12 h gave the [CpRu(IV)( p-C3H5)(2-quino-
linecarboxylato)]PF6 complex; yield: 3.93 g(7.50 mmol),
99%); anal. calcd. for C18H16F6NO2PRu: C 41.23, H 3.08, N
nolinecarboxylato)]PF6 (6; 2.3 mg, 4.4 mmol) was placed in an-
other 20-mL Schlenk tube equipped with a Youngꢁs tap under
an argon stream. To this was added the 2a and 2-propen-1-ol
solution through a cannula under an argon stream. The yellow
homogeneous solution was stirred for 3 h in a 708C oil bath.
GC analysis determined the yield of allyl 2-phenylethyl ether
(1a) to be 93%.[11]
Acknowledgements
This work was aided by a Grant-in-Aid for Scientific Research
(No. 14078212) from the Ministry of Education, Science, Sports
and Culture, Japan. We are grateful to Messrs. T. Noda, K. Oya-
ma, and Y. Maeda for their technical support in reaction vessel
production and spectral measurements.
1
2.67; found: C 41.48, H 2.95, N 2.73. The H- and 13C-NMR,
References and Notes
HR-mass, and IR spectra were consistent with those reported
in the previous paper.[6]
´
[1] F. Guibe, Tetrahedron 1997, 53, 13509–13556; T. W.
The complex (100 mg) was kept in a screw-capped vial at
278C for six months. The catalytic activity of the stored com-
plex in the deallylation of 1a was identical to that of freshly pre-
pared 6 (Table 1, entries 1 and 2).
Greene, P. G. M. Wuts, Protective Groups in Organic
Synthesis, 3rd edn., John Wiley & Sons, New York, 1999.
[2] Rh: E. J. Corey, J. W. Suggs, J. Org. Chem. 1973, 38, 3224;
Ir: J. J. Oltvoort, C. A. A. van Boeckel, J. H. de Koning,
J. H. van Boom, Synthesis 1981, 305–308; for a recent pa-
per, see: C. Cadot, P. I. Dalko, J. Cossy, Tetrahedron Lett.
2002, 43, 1839–1841, and references cited therein.
[3] Ni: a) T. Taniguchi, K. Ogasawara, Angew. Chem. Int.
Ed. 1998, 37, 1136–1137; Pd: b) H. Murakami, T. Mina-
mi, F. Ozawa, J. Org. Chem. 2004, 69, 4482–4486; c) H.
Tsukamoto, Y. Kondo, Synlett 2003, 1061–1063;
d) D. R. Vutukuri, P. Bharathi, Z. Yu, K. Rajasekaran,
M.-H. Tran, S. Thayumanavan, J. Org. Chem. 2003, 68,
1146–1149; e) S. Chandrasekhar, C. R. Reddy, R. J.
Rao, Tetrahedron 2001, 57, 3435–3438; f) M. Honda, H.
Morita, I. Nagakura, J. Org. Chem. 1997, 62, 8932–
8936; g) R. Beugelmans, S. Bourdet, A. Bigot, J. Zhu,
Tetrahedron Lett. 1994, 35, 4349–4350; Os: h) P. I. Kitov,
D. R. Bundle, Org. Lett. 2001, 3, 2835–2838.
Deallylation
[CpRu(p-C3H5)(2-quinolinecarboxylato)]PF6 (6; 1.9 mg,
3.7 mmol) was placed in a 20-mL Schlenk tube under an argon
stream. To this was added a mixture of allyl 2-phenylethyl ether
(1a; 0.300 g, 1.85 mmol) and methanol (3.4 mL) which was de-
gassed three times by the freeze-thaw method via a cannula.
The yellow solution was stirred for 3 h at 308C. GC analysis de-
termined the yield of 2-phenylethanol (2a) to be >99%.[11] The
reaction mixture was concentrated under reduced pressure to
give a crude product, which was separated by chromatography
on silica gel (AP 300, 15 g; eluent, 7:3 hexane–ethyl acetate) to
1
give pure 2a; yield: 0.225 g(99%). H NMR (600 MHz, CDCl3):
d¼2.88 (t, 2H, J¼6.42 Hz, C6H5CH2), 3.87 (t, 2H, J¼6.42 Hz,
CH2CH2OH), 7.23–7.34 (m, 5H, aromatic).
[4] S. Tanaka, H. Saburi, Y. Ishibashi, M. Kitamura, Org.
Lett. 2004, 6, 1873–1875.
[5] For allyl ester cleavage using 3 and triphenylphosphine,
see: M. Kitamura, S. Tanaka, M. Yoshimura, J. Org.
Chem. 2002, 67, 4975–4977.
[6] H. Saburi, S. Tanaka, M. Kitamura, Angew. Chem. Int.
Ed. 2005, 44, 1730–1732.
[7] Other example of activation of allyl alcohol by use of Pd
complex, see: F. Ozawa, T. Ishiyama, S. Yamamoto, S.
Kawagishi, H. Murakami, M. Yoshifuji, Organometallics
2004, 23, 1698–1707; see also ref.[3b]
Allylation
No solvent system: 2-Phenylethan-1-ol (2a; 0.782 g, 6.40 mmol)
and 2-propen-1-ol (0.372 g, 6.40 mmol) were placed in a 20-mL
Schlenk tube equipped with a Youngꢁs tap, and the whole mix-
ture was degassed three times by the freeze-thaw method.
[CpRu(p-C3H5)(2-quinolinecarboxylato)]PF6 (1.7 mg, 3.2 mmol)
was placed in another 20-mL Schlenk tube equipped with a
Youngꢁs tap under an argon stream. To this was added the 2a
and 2-propen-1-ol mixture through a cannula under an argon
stream. The yellow homogeneous mixture was stirred at
708C for 6 h. GC analysis determined the yield of allyl 2-phe-
nylethyl ether (1a) to be 92%.[11]
[8] The Ru(II) complex consistingof [CpRu(II)(CH CN)3]-
3
PF6 and 2-quinolinecarboxylic acid decomposes under
aerobic conditions, leadingto deactivation of the cata-
lyst.
[9] For the original papers on the donor-acceptor bifunction-
al catalyst, see: R. Noyori, M. Kitamura, Angew. Chem.
Int. Ed. Engl. 1991, 30, 49–69; M. Kitamura, S. Suga,
K. Kawai, R. Noyori, J. Am. Chem. Soc. 1986, 108,
6071–6072.
CH2Cl2 system: 2-Phenylethan-1-ol (2a; 0.268 g,
2.19 mmol), 2-propen-1-ol (0.127 g, 2.19 mmol), and dichloro-
methane (4.0 mL) were placed in a 20-mL Schlenk tube equip-
ped with a Youngꢁs tap, and the whole mixture was degassed
three times by the freeze-thaw method. [CpRu(p-C3H5)(2-qui-
Adv. Synth. Catal. 2006, 348, 375 – 378
ꢀ 2006 Wiley-VCH VerlagGmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
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