SILVER 1
Ag, THF
Silver
BuBr + BuMgBr (2)
C8H18
25 °C, 5 h
79%
Ag
When supported on Alumina silver effects the coupling of per-
fluoroalkyl iodides with alkenes at high temperatures (eq 3),3 and,
[7440-22-4] Ag (MW 107.87)
in combination with Zinc, it enables the preparation of highly
InChI = 1/Ag
strained alkenes from halogen-bearing precursors (eq 4).4
InChIKey = BQCADISMDOOEFD-UHFFFAOYAU
Ag/Al2O3
C8H17I + H2C=CH2 (3)
C8H17CH2CH2I
125 °C, 11 h
(catalyst for valence isomerizations1 and for coupling reactions
94.5%
involving Grignard reagents,2 alkenes,3 and carbenoid species4)
ć%
Br Cl
Physical Data: white, lustrous, malleable metal; mp 960.5 C.
Solubility: insol most solvents, but see preparation of  soluble
Cl
Ag, Zn
silver below.
THF, ", 10 h 34%
Form Supplied in: widely available as rods, wire, foil, powder, Cl
etc.
Preparative Method:  soluble silver is prepared as follows:
Silver(I) Nitrate (5 mmol) is treated in ether with a 1.0 M solu-
ć%
(4)
tion of Ethylmagnesium Bromide (30 mL) at 0 Cfor 3h; the
supernatant is 7.5 M in soluble silver and stable at refrigerator
temperatures.2
Handling, Storage, and Precautions: the powder is flammable,
and may cause skin and/or eye irritation.
Although the predominant use of silver as a catalyst is in in- 1. Burger, U.; Mazenrod, F., Tetrahedron Lett. 1976, 2885.
dustrial oxidation processes,5 it has found use in laboratory appli- 2. Tamura, M.; Kochi, J., Synthesis 1971, 303.
cations, as in the valence isomerization of benzvalene to benzene
3. von Werner, K., J. Fluorine Chem. 1985, 28, 225.
(eq 1).1 It also enables the smooth coupling of Grignard reagents
4. Kumar, A.; Friedli, F. E.; Hsu, L.; Card, P. J.; Mathur, N.; Shechter, H., J.
with bromides, although both alkyl groups must be the same to Org. Chem. 1991, 56, 1663.
ensure acceptable yields (eq 2).2
5. Margolis, L. Y.; Firsova, A. A., Int. Rev. Phys. Chem. 1989, 8, 1.
Ag, Et2O
T. Howard Black
(1)
Eastern Illinois University, Charleston, IL, USA
Avoid Skin Contact with All Reagents