cacodyl oxide

{{chembox

| Verifiedfields = changed

| Watchedfields = changed

| verifiedrevid = 417523735

| Name = Cacodyl oxide

| OtherNames = TL-297

| ImageFile = Cacodyl-oxide-3D-bs-17.png

| ImageName = Ball-and-stick model of cacodyl oxide

| ImageFile1 = Me4As2O.png

| ImageName1 = Line structure model of cacodyl oxide

| PIN = Dimethylarsinous anhydride

|Section1={{Chembox Identifiers

| CASNo_Ref = {{cascite|correct|??}}

| CASNo = 503-80-0

| PubChem = 10431

| SMILES = C[As](C)O[As](C)C

| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}

| ChemSpiderID = 10002

| InChI = 1/C4H12As2O/c1-5(2)7-6(3)4/h1-4H3

| InChIKey = LOKPKYSOCCPWIZ-UHFFFAOYAL

| StdInChI_Ref = {{stdinchicite|changed|chemspider}}

| StdInChI = 1S/C4H12As2O/c1-5(2)7-6(3)4/h1-4H3

| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}

| StdInChIKey = LOKPKYSOCCPWIZ-UHFFFAOYSA-N

}}

|Section2={{Chembox Properties

| Formula = C₄H₁₂As₂O

| MolarMass = 255.98 g/mol

| Density =

| MeltingPt =

| BoilingPt =

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Cacodyl oxide is a chemical compound of the formula [(CH₃)₂As]₂O. This organoarsenic compound is primarily of historical significance since it is sometimes considered to be the first organometallic compound synthesized in relatively pure form.{{ cite book | author = Elschenbroich, C. | title = Organometallics | year = 2006 | publisher = Wiley-VCH | location = Weinheim | isbn = 9783527293902 }}{{cite journal | title = Cadet's Fuming Arsenical Liquid and the Cacodyl Compounds of Bunsen | first = D. | last = Seyferth | journal = Organometallics | year = 2001 | volume = 20 | issue = 8 | pages = 1488–1498 | doi = 10.1021/om0101947 | doi-access = free }}

"Cadet's fuming liquid", which is composed of cacodyl and cacodyl oxide, was originally synthesized by heating potassium acetate with arsenic trioxide. It has a disagreeable odor and is toxic.

The molecular structure of [Ph₂As]₂O (Ph = phenyl), the tetraphenyl analogue of cacodyl oxide, has been established by X-ray crystallography.{{cite journal |doi=10.1039/b005269h|title=Group 6 transition metal carbonyl complexes with chalcogen-bridged diarsenic(III) ligands|year=2000|last1=Doerrer|first1=Linda H.|last2=Green|first2=Jennifer C.|last3=Green|first3=Malcolm L. H.|last4=Haiduc|first4=Ionel|last5=Jardine|first5=Christian N.|last6=Pascu|first6=Sofia I.|last7=Silaghi-Dumitrescu|first7=Luminita|last8=Watkin|first8=David J.|journal=Journal of the Chemical Society, Dalton Transactions|issue=19|pages=3347–3355}}