Iodine-Silver(I) Fluoride

I2-AgF
(I2)

[7553-56-2]  · I2  · Iodine-Silver(I) Fluoride  · (MW 253.80) (AgF)

[7775-41-9]  · AgF  · Iodine-Silver(I) Fluoride  · (MW 126.87)

(source of electrophilic iodine, I+, in electrophilic aromatic substitution reactions;1 IF addition reagent across double bonds;2 mild oxidant which fluoridates selected polycyclic aromatic hydrocarbons via radical cationic intermediates3)

Physical Data: AgF: mp 435 °C; bp 1150 °C; d 5.85 g cm-3.

Solubility: AgF: sol acetonitrile; sparingly sol aromatic and halogenated solvents.

Form Supplied in: AgF: orange and brown chunks.

Handling, Storage, and Precautions: AgF: corrosive, harmful dust, hygroscopic, light sensitive. This reagent should be handled in a fume hood.

Electrophilic Reactions.

Up to 50% yield of an aryl iodide is obtained when Iodine and Silver(I) Fluoride are added to neat, activated aromatic compounds; much poorer yields result if the aromatic compound is weakly activated or deactivated toward electrophilic aromatic substitution (eq 1)1 (see Trifluoroacetyl Hypoiodite for a superior iodinating reagent in electrophilic aromatic substitution reactions). Quantitative trans addition to double bonds is observed when a dilute solution of iodine (or bromine) in benzene is slowly added to a suspension of AgF in a solution of the target alkene in benzene (eq 2).2

Fluorination.

Polycyclic aromatic hydrocarbons with low oxidation potentials are oxidized by the Ag+/Ag redox couple to radical cations which are attacked by a fluoride nucleophile to give low yields (10-50%) of fluorinated products.3


1. Bergmann, E. D.; Shahak, I. JCS 1959, 1418.
2. Hall, L. D.; Jones, D. L. CJC 1973, 51, 2902.
3. O'Malley, R. F.; King, R. F. JOC 1984, 49, 2803.

Ronald G. Brisbois & Randall A. Wanke

Hamline University, St. Paul, MN, USA



Copyright 1995-2000 by John Wiley & Sons, Ltd. All rights reserved.