F. Cßetin et al. / Journal of Organometallic Chemistry 689 (2004) 154–157
157
used to combine with electrophiles to give coupled
products in moderate yields. The conditions for these
reactions are both mild and extremely accessible. Thus
the N,N-diethylbenzamide derivative (1e) is metallated
at 0 °C over 30 min. In contrast, the traditional proce-
dure for the preparation of orthometallated benzamide
derivatives would involve first orthometallation of N,N-
diethylbenzamide at )78 °C by the use of a sec-BuLi–
TMEDA complex [13]. This would then be followed by
transmetallation reactions [13–15]. These conditions are
clearly less convenient than for our procedure. Fur-
thermore the use of the Li reagent in the initial step
clearly limits the number of functional groups that can
be tolerated. In contrast, our procedure only involves
(3) N,N-diethyl-2-(phenylmethyl)benzamide (5e) [13].
ꢁ
1
1
IR (cm ) 1634, 1428; H NMR 7.10–7.40 (9H, m), 3.95
(2H, br), 3.57 (1H, br), 3.29 (1H, br), 2.76 (2H, br) 1.11
(3H, t, J ¼ 7:1), 0.88 (3H, t, J ¼ 7:1).
Acknowledgements
We thank the Science Faculty of Ege University and
the Scientific and Technical Research Council of Turkey
€
(TUBITAK) for their financial support.
_
the use of Ph CuLi ꢀ LiCN and so such a problem is not
2
inherent. Therefore, we feel strongly that this method
bears further potential for the coupling of certain sen-
sitive and functionally substituted organic com-
pounds where both mild and convenient conditions are
desirable.
References
[
[
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(
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[
[
(
(
(
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3
. Experimental
Oxazoline derivatives were prepared according to the
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for 30 min. A weighed sample of aryl halide (0.25 eq)
was subsequently added dropwise to the mixture. Opti-
mum times and temperatures for these reactions are
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ded dilute NH4Cl solution (Table 1) or electrophile
2
4
(
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[
1
4 (2000) 341.
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(
9] W.E. Parham, C.K. Bradsher, Acc. Chem Res. 15 (1982) 300.
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[
chromatography using Si gel and hexane/ethyl acetate
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[
[
10] A.I. Meyers, B.E. Williams, Tetrahedron Lett. (1978) 223.
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(
1
analysed by IR, and H NMR spectroscopy. All prod-
ucts have been previously prepared and comparisons of
spectroscopic data with literature data were made.
0
(
1) 2-(1,1 -biphenyl)-4,5-dihydro-4,4-dimethyloxazole
ꢁ
1
1
(
(
7
4) [14]. IR (cm ) 1649, 1457; H NMR (CDCl3) d 7.65
1H, d, J ¼ 7:7 Hz) 7.41 (1H, td, J ¼ 7:5, J ¼ 1:4 Hz),
t
d
[12] T.T. Tsou, J.K. Kochi, J. Am. Chem. Soc. 101 (1979) 6319.
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.23–7.35 (7H, m), 3.79 (2H, s), 1.20 (6H,s).
0
[
(
2) 2-(2 -(phenylmethyl)phenyl)-4,5-dihydro-4,4-dimeth-
ꢁ
1
1
[15] J.F. Eaddy, Org. Prep. Proc. Int. 27 (1995) 367.
yloxazole (5a) [17]. IR (cm ) 1640, 1455; H NMR
CDCl3) d 7.68 (1H, dd, J ¼ 7:7, 1.3 Hz) 7.27 (1H, td,
Jt ¼ 7:5, Jd ¼ 1:4 Hz), 7.04–7.20 (7H, m), 4.35 (2H, s),
.85 (2H, s), 1.20 (6H, s).
[
[
16] A.I. Meyers, D.L. Temple, D. Haidukewych, E.D. Mihelich,
J. Org. Chem. 39 (1974) 2787.
(
17] J.M. Kane, C.R. Dalton, N.L. Velago, D. Rampe, Biorg. Med.
Chem. Lett. 5 (1995) 873.
3