[563-63-3] · C2H3AgO2 · Silver(I) Acetate · (MW 166.92)
Alternate Names: silver acetate; silver monoacetate.
Physical Data: d 3.26 g cm-3.
Solubility: sol in 100 parts of cold water, 35 parts of boiling water; freely sol dil nitric acid.
Form Supplied in: white to slightly grayish lustrous needles or crystal powder.
Handling, Storage, and Precautions: causes irritation to skin, eyes, mucous membranes, and upper respiratory tract. May cause discoloration of skin and deep tissues. In case of contact with skin or eyes, immediately rinse with copious amounts of water. Light sensitive. Store in cool dry place. Incompatible with strong oxidizing agents and strong acids. May discolor on exposure to light.
Alcohols that have a hydrogen in the d-position can be cyclized with silver acetate and Bromine (eq 1). The ring closure occurs via an intermediate hypobromite. The reaction can be run under a variety of conditions (presence/absence of light, acidity, solvent, temperature). Because of this variety and the products formed, there has been some disagreement about the role silver plays in the hypobromite decomposition.1
Regioselective ring contractions are possible via bromination of cyclobutyl ketones. The intermediate bromo ketone, when treated with silver acetate in acetic acid (120 °C, 6 h), affords a mixture of the cyclopropyl ketone and the acetoxy ketone (57% and 28% isolated yield, respectively, eq 2).2
Ring expansions and chain extensions are observed when gem-dihalocyclopropanes, derived from alkenes, are treated with silver acetate and acetic acid (eqs 3 and 4).3
When meso-stilbene dibromide is heated with silver acetate under anhydrous conditions, the product is the meso-diol diacetate (eq 5). However, when the starting material is heated for 10 min on a steam bath with silver acetate, acetic acid, and water, a significant amount of (±)-diol monoacetate is formed.4
There has been extensive reporting of the use of silver acetate for direct nucleophilic substitution.5 3-Chloroindolenines react with silver acetate to give the product of direct displacement (eq 6). This is in contrast to reactions with softer nucleophiles (I-, PhS-, PO3) which give the parent indole.6
Reacting p-cyclohexenylpalladium complexes with stoichiometric amounts of silver acetate, and then with carbon monoxide and benzene, produces the diastereoisomerically pure (>95%) allylic acetate (yield 70%) (eq 7).7
Halofluorocyclopropanes are opened with silver acetate in acetic acid (eq 8).8 Arenes can be oxidized with silver acetate in the presence of 2,2´-bipyridine and potassium peroxydisulfate in high yields (eq 9).9
Acetyl hypobromite is generated when a bromine/carbon tetrachloride solution is added to a stirred suspension of silver acetate in carbon tetrachloride. This solution can then be used in the conversion of alkenes to bromohydrin acetates (eq 10).10
The Simmons-Smith reagent is generated by adding granular Zinc to a hot solution of silver acetate in acetic acid (eq 11). The Zinc/Silver Couple is decanted and washed with acetic acid and ether. The addition of a small amount of silver wool assures stabilization. Silyl enol ethers can be cyclopropanated using this reagent in good to moderate yields (ca. 75%). Acid hydrolysis can be avoided by the addition of an amine to the mixture.11 An example of the use of this reagent is in the conversion of 2,3-bis(trimethylsiloxy)-1,3-butadiene to the bicyclopropyl derivative (eq 12).12
Sulfenamides can be synthesized by a metal-assisted reaction with disulfides and amines (eq 13).13 Conjugated dienols can be synthesized in a highly chemo-, regio-, and stereoselective manner from vinylic halides and allylic alcohols (eq 14). Silver acetate (or silver carbonate) and a catalytic amount of Palladium(II) Acetate in DMF are the preferred conditions. The reaction is very attractive because it requires only one functionalized alkene reactant and the addition of the vinylic group only occurs at the terminal carbon of the allylic alcohol.14
N-Bromoacetamide-Silver Acetate-Acetic Acid;
Mary K. Balmer & Brian A. Roden
Abbott Laboratories, North Chicago, IL, USA