8000
Y.-G. Lim, B. T. Koo / Tetrahedron Letters 46 (2005) 7997–8001
for coordination. This result showed that a substituent
at meta-position to the coordinated aldimine affected
the reactivity of this alkylation.
T. Tetrahedron Lett. 1999, 40, 7691; (g) Lim, Y.-G.; Han,
J.-S.; Koo, B. T.; Kang, J.-B. Polymer 2000, 41, 4351; (h)
Lim, Y.-G.; Han, J.-S.; Yang, S.-S.; Chun, J. H. Tetra-
hedron Lett. 2001, 42, 4853; (i) Lim, Y.-G.; Lee, K.-H.;
Koo, B. T.; Kang, J.-B. Tetrahedron Lett. 2001, 42, 7609;
To prove this meta-substituent effect, substrate 1d hav-
ing two big alkyl groups at sites 2 and 6 was applied
to this alkylation. This substrate has two alkyl groups
at only meta-position to the aldimine for the coordina-
tion. Substrate 1d did not react with 2a completely
under the same reaction conditions as shown in Scheme
(
j) Lim, Y.-G.; Kang, J.-B.; Lee, K.; Kim, Y. H.
Heteroatom Chem. 2002, 13, 346; (k) Lim, Y.-G.; Han,
J.-S.; Koo, B. T.; Kang, J.-B. J. Mol. Catal. A: Chem.
2
004, 209, 41; (l) Lim, Y.-G.; Koo, B. T. Tetrahedron Lett.
2005, 46, 385.
3. (a) Murai, S.; Kakiuchi, F.; Sekine, S.; Tanaka, Y.;
Kamatani, A.; Sonoda, M.; Chatani, N. Nature 1993, 366,
4
. Consequently, it showed that meta-substituents to the
5
29; (b) Kakiuchi, F.; Sekine, S.; Tanaka, Y.; Kamatani,
aldimine group for the coordination affected to this
alkylation extensively.
A.; Sonoda, M.; Chatani, N.; Murai, S. Bull. Chem. Soc.
Jpn. 1995, 68, 62; (c) Kakiuchi, F.; Tanaka, Y.; Sato, T.;
Chatani, N.; Murai, S. Chem. Lett. 1995, 679; (d) Fujii,
N.; Kakiuchi, F.; Chatani, N.; Murai, S. Chem. Lett. 1996,
The exact mechanism is unclear at this time. However,
we deduced the proposed mechanism from the above
results. The mechanism of this alkylation is proposed
to be similar to that previously reported, except meta-
substitutent effect as shown in Scheme 5. When rhodium
metal coordinates to the nitrogen of two different types
of aldimines, the choice of aldimine by rhodium metal
can be affected by the steric and electronic effects.
In the case of the coordination of the rhodium metal
to the nitrogen of the aldimine having ortho-alkyl group,
the alkyl group, as an electron-donating group, stabi-
lizes the intermediate. But, the one at the opposite side
cannot receive help from the alkyl group. Moreover,
meta-substitutent disturbs the approach of rhodium
metal to the nitrogen of aldimine because of the steric
hindrance between a substituent and a ligand like B. So
the rhodium metal favors the nitrogen of the aldimine
having ortho-alkyl group rather than the one at the other
side to give the intermediate A. And then, the insertion
of alkene into the Rh–H bond in A gives the linear alkyl
rhodium intermediate C according to the anti-Mark-
ovnikov rule. The intermediate C gives the alkylated
product F by reductive elimination. The intermediate
B formed with difficult gives H as a minor product.
9
39; (e) Sonoda, M.; Kakiuchi, F.; Kamatani, A.; Chatani,
N.; Murai, S. Chem. Lett. 1996, 109; (f) Kakiuchi, F.;
Yamauchi, M.; Chatani, N.; Murai, S. Chem. Lett. 1996,
111; (g) Fujii, N.; Kakiuchi, F.; Yamada, A.; Chatani, N.;
Murai, S. Chem. Lett. 1997, 425; (h) Fujii, N.; Kakiuchi,
F.; Yamada, A.; Chatani, N.; Murai, S. Bull. Chem. Soc.
Jpn. 1998, 71, 285; (i) Kakiuchi, F.; Sato, T.; Tsujimoto,
T.; Yamauchi, M.; Chatani, N.; Murai, S. Chem. Lett.
1
998, 1053; (j) Kakiuchi, F.; Sato, T.; Yamauchi, M.;
Chatani, N.; Murai, S. Chem. Lett. 1999, 19; (k) Kakiuchi,
F.; Sonoda, M.; Tsujimoto, T.; Chatani, N.; Murai, S.
Chem. Lett. 1999, 1083; (l) Kakiuchi, F.; Gendre, P. L.;
Yamada, A.; Ohtaki, H.; Murai, S. Tetrahedron: Asym-
metry 2000, 11, 2647; (m) Asaumi, T.; Matsuo, T.;
Fukuyama, T.; Ie, Y.; Kakiuchi, F.; Chatani, N. J. Org.
Chem. 2004, 69, 4433.
4. (a) Jun, C.-H.; Hong, J.-B.; Kim, Y.-H.; Chung, K.-Y.
Angew. Chem., Int. Ed. 2000, 39, 3440; (b) Jun, C.-H.;
Moon, C. W.; Lee, D.-Y. Chem. Eur. J. 2002, 8, 2423; (c)
Lim, S.-G.; Lee, J. H.; Moon, C. W.; Hong, J.-B.; Jun,
C.-H. Org. Lett. 2003, 5, 2759.
. (a) Tan, K. L.; Park, S.; Ellman, J. A.; Bergman, R. G.
J. Org. Chem. 2004, 69, 7329; (b) Wiedemann, S. H.;
Bergman, R. G.; Ellman, J. A. Org. Lett. 2004, 6, 1685; (c)
Thalji, R. K.; Ellman, J. A.; Bergman, R. G. J. Am. Chem.
Soc. 2004, 126, 7192.
5
In conclusion, we have found that terephthaldialdimine
6. Trost, B. M.; Imi, K.; Davies, I. W. J. Am. Chem. Soc.
1995, 117, 5371.
1
a reacted with alkenes to give 2,6-dialkylated products
7
. Lenges, C. P.; Brookhart, M. J. Am. Chem. Soc. 1999, 121,
616.
selectively in moderate to high isolated yields. In the
case of terephthaldialdimine 1b having a substituent at
site 2 in the phenyl ring, the alkylation takes place selec-
tively at site 6 in the phenyl ring. In this alkylation, a
meta-substituent affected the reactivity significantly
because of the steric hindrance.
6
8
. (a) Guari, Y.; Sabo-Etienne, S.; Chaudret, B. J. Am.
Chem. Soc. 1998, 120, 4228; (b) Guari, Y.; Castellanos, A.;
Sabo-Etienne, S.; Chaudret, B. J. Mol. Catal. A: Chem.
2
004, 212, 77.
9
. (a) Miura, M.; Tsuda, T.; Satoh, T.; Pivsa-Art, S.;
Nomura, M. J. Org. Chem. 1998, 63, 5211; (b) Satoh,
T.; Nishinaka, Y.; Miura, M.; Nomura, M. Chem. Lett.
1999, 615.
References and notes
1
0. Matsumoto, T.; Taube, D. J.; Periana, R. A.; Taube, H.;
1
2
. (a) Ritleng, V.; Sirlin, C.; Pfeffer, M. Chem. Rev. 2002,
02, 1731; (b) Guari, Y.; Sabo-Etienne, S.; Chaudret, B.
Eur. J. Inorg. Chem. 1999, 1047; (c) Kakiuchi, F.; Murai,
S. Acc. Chem. Res. 2002, 35, 826; (d) Kakiuchi, F.;
Chatani, N. Adv. Synth. Catal. 2003, 345, 1077.
. (a) Lim, Y.-G.; Kim, Y. H.; Kang, J.-B. J. Chem. Soc.,
Chem. Commun. 1994, 2267; (b) Lim, Y.-G.; Kang, J.-B.;
Kim, Y. H. Chem. Commun. 1996, 585; (c) Lim, Y.-G.;
Kang, J.-B.; Kim, Y. H. J. Chem. Soc., Perkin Trans. 1
Yoshida, H. J. Am. Chem. Soc. 2000, 122, 7414.
11. Bi, S.; Lin, Z.; Jordan, R. F. Organometallics 2004, 23,
1
4882.
12. Krebs, F. C.; Jørgensen, M. Macromolecules 2003, 36, 4374.
1
13. Selected analytical data. Compound 4a:
(600 MHz, CDCl
4-CHO), 7.58 (s, 2H, 3,5-Hs in Ar), 2.91–2.94 (m, 4H,
a-CH to Ar), 1.46–1.50 (m, 4H, b-CH to Ar), 0.99
(s, 18H, CH ); C NMR (150 MHz, CDCl ) 193.36,
H NMR
) 10.59 (s, 1H, 1-CHO), 10.02 (s, 1H,
3
2
2
1
3
3
3
1
996, 2201; (d) Lim, Y.-G.; Kang, J.-B.; Kim, Y. H. J.
192.01, 146.92, 138.42, 136.90, 129.51, 46.89, 30.86,
29.19, 28.78; IR (KBr, neat, cm ) 2954 (s), 2905 (m),
2867 (m), 1696 (vs, C@O), 1571 (w), 1466 (m), 1365 (m),
1247 (w), 1186 (m), 876 (w), 809 (w), 755 (w); MS (m/z)
À1
Chem. Soc. Perkin. Trans. 1 1998, 699; (e) Lim, Y.-G.;
Han, J.-S.; Koo, B. T.; Kang, J.-B. Bull. Korean Chem.
Soc. 1999, 20, 1097; (f) Lim, Y.-G.; Kang, J.-B.; Koo, B.