J. Am. Chem. Soc. 1999, 121, 5819-5820
5819
Nickel on Charcoal (“Ni/C”): An Expedient and
Inexpensive Heterogeneous Catalyst for
Cross-Couplings between Aryl Chlorides and
Organometallics. I. Functionalized Organozinc
Reagents
Table 1. Reactions of Aryl Chlorides with Functionalized Zinc
Reagents Catalyzed by Ni/C
Bruce H. Lipshutz* and Peter A. Blomgren
Department of Chemistry
UniVersity of California
Santa Barbara, California 93106
ReceiVed February 11, 1999
Although organopalladium chemistry continues to offer a
wealth of impressive opportunities for the elaboration of molecular
1
architecture, as with any metal, there are limitations. Within the
group 10 triad, processes mediated by organonickel complexes
have begun to claim an increasing share of the carbon-carbon
bond-forming spotlight normally reserved for its southern neigh-
2
3a
3b
bor. Such inveterate “name” reactions as Negishi, Suzuki, and
Stille3 couplings, among others, which historically are Pd(0)-
c
3d
driven, are now being scanned with varying levels of success
4
under Ni(0) catalysis. Aside from the many virtues of nickel (e.g.,
its low cost, usually greater reactivity, etc.), essentially all of its
5
known C-C-bond forming chemistry takes place in solution. In
this report, we disclose the first successful, seemingly general,
use of in situ generated nickel(0) on charcoal (“Ni/C”) as an
efficient heterogeneous catalyst for mediating carbon-carbon
bond constructions involving chloroarenes and functionalized
organozinc reagents.
6
3 2
Nickel(II) is best impregnated on carbon using Ni(NO )
together with a commercial source of charcoal that is of high
7
surface area. Admixture of the charcoal, e.g., together with 5
mol % by weight of an aqueous solution of this nickel salt,
a
b
Fully characterized by IR, NMR, MS, and HRMS data. Isolated,
chromatographically purified materials. c EtOAc was used as the solvent
due to the poor solubility of the zinc reagent in THF.
*
Corresponding author. Telephone: 805-893-2521. Fax: 805-893-8265.
E-mail: lipshutz@chem.ucsb.edu.
1) Tsuji, J. Palladium Reagents and Catalysis; John Wiley and Sons
Ltd.: Chichester, 1995.
2) New Developments in Organonickel Chemistry. Tetrahedron Symposium-
(
followed by evaporation of the water, washing with water and
THF, and then drying under vacuum at room temperature, affords
Ni(II)/C. Although this black powdery material was originally
shown to be reduced to Ni(0) by heating to 400 °C, more recently
it has been found that such treatment adversely alters the texture
(
in-Print, Number 69; Lipshutz, B. H., Luh, T.-Y., Eds.; Tetrahedron 1998,
5
4, 1021-1316.
8
(
3) (a) Negishi, E.; King, A. O.; Okukado, N. J. Org. Chem. 1977, 42,
1
821. (b) Miyaura, N.; Suzuki, A. Chem. ReV. 1995, 95, 2457. (c) Stille, J.
K. Angew. Chem., Int. Ed. Engl. 1986, 25, 508. (d) Sonogashira, K.; Tohda,
Y.; Hagihara, N. Tetrahedron Lett. 1975, 4467.
(4) (a) Brenner, E.; Fort, Y. Tetrahedron Lett. 1998, 39, 5359; Indolese,
(8) Procedure for preparing Ni(II)/C: Darco activated carbon [KB 100
2
3
A. F. ibid. 1997, 38, 3513. (b) Saito, S.; Oh-tani, S.; Miyaura, N. J. Org.
Chem. 1998, 63, 8024. (c) Mann, G.; Hartwig, J. F. ibid. 1997, 62, 5413;
Shirakawa, E.; Yamasaki, K.; Hiyama, T. J. Chem. Soc., Perkin Trans. 1 1997,
mesh, lot No. 05031AR, surface area 1500 m /g, pore volume 1.5 cm /g, <30%
H
2
O] (5.00 g) was dried under vacuum (100 °C, 0.5 mmHg) for 12 h to yield
O (75 mL) was
3.75 g of dried material (for weight purposes only). H
2
1
7, 2449; Saito, S.; Oh-tani, S.; Miyaura, N. J. Org. Chem. 1997, 62, 8024.
deoxygenated by vigorously bubbling argon through the liquid for 2 h and
was added to a 100-mL round-bottom flask containing the dried carbon and
(
d) Quesnelle, C. A.; Familoni, O. B.; Snieckus, V. Synlett 1994, 349. (e)
Littke, A. F.; Fu, G. C. Angew. Chem., Int. 1998, 37, 3387. (f) Old, D. W.;
Wolfe, J. P.; Buchwald, S. L. J. Am. Chem. Soc. 1998, 120, 9722. (g) Lipshutz,
B. H.; Blomgren, P. A.; Kim, S.-K. Tetrahedron Lett. 1999, 40, 197. (h) Miller,
J. A.; Farrell, R. P. ibid. 1998, 39, 6441. (i) Nan, Y.; Yang, Z. ibid. 1999, 40,
an efficient magnetic stir bar. Ni(NO
in H
3 2
) ‚6H
2
O (545 mg, 1.87 mmol) dissolved
O (5 mL, deoxygenated) was then added to the stirring suspension and
2
the mixture heated in a sand bath equilibrated at 170 °C. The water was allowed
to distill under an atmosphere of argon until the mixture was dry. The sand
bath was then cooled, undistilled, degassed THF (50 mL) was introduced,
and the mixture was placed in a sand bath equilibrated to 100 °C, and the
liquid was distilled under Ar. The black solid was then washed with degassed
3
321. (j) Galland, J. C.; Savignac, M.; Genet, J. P. ibid. 1999, 40, 2323.
5) For related chemistry using nanostructured nickel clusters, see: Reetz,
M. T.; Breinbauer, R.; Wedemann, P.; Binger, P. Tetrahedron 1998, 54, 1233.
6) Use of alternative Ni(II) salts, e.g., NiCl , did not lead to an active
catalyst as most of the metal was easily washed off the charcoal.
7) Gil, A.; Gandia, L. M.; Montes, M. J. Phys. Chem. Sol. 1997, 58(7),
079; Gandia, L. M.; Montes, M. J. Catal. 1994, 145, 276-288; Garcia, M.
D.; Marales, I. F.; Garzon, F. J. L. Appl. Catal. A 1994, 112, 75.
(
(
2
H
2
O (3 × 100 mL) and distilled THF (2 × 100 mL) and then dried under
vacuum (0.5 mmHg) at 100 °C with stirring for 12 h. Evaporation of the
filtrates led to recovery of 113 mg (0.39 mmol) of Ni(II). Thus, 0.27 g (1.48
mmol) Ni(II) was adsorbed onto 3.75 g of charcoal, leading to 1.48 mmol/
4.02 g (total weight) or 0.37 mmol Ni(II)/g C.
(
1
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0.1021/ja990432d CCC: $18.00 © 1999 American Chemical Society
Published on Web 06/06/1999