Mercury(II) acetate

Mercury(II) acetate
Other names mercuric acetate mercuriacetate
Identifiers
CAS number	1600-27-7 Y
ChemSpider	14599 Y
UNII	R0G1MCT8Y5 Y
ChEBI	CHEBI:33211 Y
Jmol-3D images	Image 1
SMILES [Hg+2].[O-]C(=O)C.[O-]C(=O)C
InChI InChI=1S/2C2H4O2.Hg/c2*1-2(3)4;/h2*1H3,(H,3,4);/q;;+2/p-2 Y Key: BRMYZIKAHFEUFJ-UHFFFAOYSA-L Y InChI=1/2C2H4O2.Hg/c2*1-2(3)4;/h2*1H3,(H,3,4);/q;;+2/p-2 Key: BRMYZIKAHFEUFJ-NUQVWONBAS
Properties
Molecular formula	C4H6O4Hg
Molar mass	318.70 g/mol
Appearance	white crystals
Density	3.27 g/cm³, solid
Melting point	179°C (decomposes)
Solubility in water	25 g/100 mL (10°C)
Solubility	soluble in alcohol
Hazards
NFPA 704	0 3 0
Y acetate (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Mercury(II) acetate is the chemical compound with the formula Hg(O₂CCH₃)₂. Commonly abbreviated Hg(OAc)₂, this compound is employed as a reagent to generate organomercury compounds from unsaturated organic precursors.

Structure

Mercury(II) acetate is a crystalline solid consisting of isolated Hg(OAc)₂ molecules with Hg-O distances of 2.07 Å. Three long, weak intermolecular Hg···O bonds of about 2.75 Å are also present, resulting in a slightly distorted square pyramidal coordination geometry at Hg.^[1]

Reactions

Arenes undergo "mercuration" upon treatment with Hg(OAc)₂. The one acetate group that remains on mercury can be displaced by chloride:^[2]

C₆H₅OH + Hg(OAc)₂ → C₆H₄(OH)-2-HgOAc + HOAc

C₆H₄(OH)-2-HgOAc + NaCl → C₆H₄(OH)-2-HgCl + NaOAc

The Hg²⁺ center binds to alkenes, inducing the addition of hydroxide and alkoxide. For example, treatment of methylacrylate with mercuric acetate in methanol gives an α-mercuri ester:^[3]

Hg(OAc)₂ + CH₂=CHCO₂CH₃ + CH₃OH → CH₃OCH₂CH(HgOAc)CO₂CH₃ + HOAc

Mercury(II) has a high affinity for sulfur ligands. Hg(OAc)₂ can be used as a reagent to remove the acetamidomethyl protecting group, which is used to "protect" thiol groups in organic synthesis. Similarly Hg(OAc)₂ is a standard reagent to convert thiocarbonate esters into dithiocarbonates:

(RS)₂C=S + H₂O + Hg(OAc)₂ → (RS)₂C=O + HgS + 2 HOAc

References

1. ^ R. Allmann (1973). Z. Kristallogr., Kristallgeom., Kristallphys., Kristallchem. 138: 366–373. 
2. ^ Whitmore, F. C.; Hanson, E. R. "o-Chloromercuriphenol" Organic Syntheses, Collected Volume 1, p.161 (1941).http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=CV1P0161
3. ^ Carter, H. E.; West, H. D. “dl-Serine” Organic Syntheses, Collected Volume 3, p.774 (1955). http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=CV3P0774