Manganese(III) acetate

Manganese Triacetate

Names
IUPAC name Manganese triacetate
Other names Manganese triacetate dihydrate; Manganese(III) acetate dihydrate
Identifiers
CAS Number	19513-05-4 (dihydrate) Y[scifinder] 26935-72-8 (anhydrous) N
3D model (Jmol)	Interactive image
ChemSpider	141084 Y
ECHA InfoCard	100.012.365
PubChem	160554
InChI InChI=1S/3C2H4O2.Mn/c3*1-2(3)4;/h3*1H3,(H,3,4);/q;;;+3/p-3 Y Key: AHSBSUVHXDIAEY-UHFFFAOYSA-K Y InChI=1/3C2H4O2.Mn/c3*1-2(3)4;/h3*1H3,(H,3,4);/q;;;+3/p-3 Key: AHSBSUVHXDIAEY-DFZHHIFOAL
SMILES [Mn+3].O=C([O-])C.[O-]C(=O)C.[O-]C(=O)C
Properties
Chemical formula	C6H9MnO6•2H2O
Molar mass	268.13 g/mol (dihydrate)
Appearance	Brown powder
Density	1.049 g cm−3, liquid; 1.266 g cm−3, solid
Hazards
R-phrases	R36/37/38, R62, R63
S-phrases	S26, S37/39
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Manganese(III) acetate is an chemical compound that is used as an oxidizing agent in organic synthesis and materials science. Like the analogous acetates of iron and chromium, it is an oxygen-centered coordination complex containing three manganese atoms bridged by acetate units. The anhydrous form of this compound crystallizes as a linear coordination polymer, with an additional acetic acid molecule bridging between manganese atoms on consecutive three-manganese clusters. The chemical is therefore not a simple metal acetate ionic compound nor does the actual structure of it reflect the simple "Mn(OAc)₃" chemical formula that is commonly given. It is usually used as the dihydrate, though the anhydrous form is also used in some situations. The dihydrate is prepared by reacting potassium permanganate and manganese(II) acetate in acetic acid; addition of acetic anhydride to the reaction produces the anhydrous form. It is also synthesized by electrochemical method starting from Mn(OAc)₂.

Mangese triacetate has been used as a single electron oxidant. It can oxidize alkenes via addition of acetic acid to form lactones.

This process is thought to proceed via the formation of a •CH₂CO₂H radical intermediate, which then reacts with the alkene, followed by additional oxidation steps and finally ring closure. When the alkene is not symmetric, the major product depends on the nature of the alkene, and is consistent with initial formation of the more stable radical (among the two carbons of the alkene) followed by ring closure onto the more stable conformation of the intermediate.

When reacted with enones, the carbon on the other side of the carbonyl reacts rather than the alkene portion, leading to α'-acetoxy enones. In this process, the carbon next to the carbonyl is oxidized by the manganese, followed by transfer of acetate from the manganese to it.