Isolation of 1,4‐Diarsinine‐1,4‐diide and 1,4‐Diarsinine Derivatives

1,4‐Diarsinine‐1,4‐diide compound [(ADCPh)As]2 (5) (ADCPh={C(DippN)}2CPh, Dipp=2,6‐iPr2C6H3) with a planar C4As2 ring fused between two 1,3‐imidazole scaffolds has been isolated as a red crystalline solid. Compound 5, formally comprising an 8π‐electron C4As2 ring, is antiaromatic and undergoes 2e‐oxidation with AgOTf to form the 6π‐electron aromatic system [(ADCPh)As]2(OTf)2 (6). KC8 reduction of a hypervalent arsenic heterocycle 4 affords the 1,4‐diarsinine‐1,4‐diide 5 as a red crystalline solid. The C4As2 ring of 5, formally comprising 8 π‐electrons, is planar and exhibits antiaromatic character. Two‐electron oxidation of 5 with AgOTf gives the 6π‐electron C4As2‐compound 6, which is an aromatic system.