Structural characteristics of 2-halo-1,3,2-dithiarsenic compounds and tris-(pentafluorophenylthio)-arsen

The combination of various dithiols and AsX3 (X = F, Cl) produces the series of cyclized halo-arsenic dithiolate compounds: 2-chloro-1,3,2-dithiarsolane [AsCl(SCH2CH2S)] (1), 2-iodo-1,3,2-dithiarsolane [AsI(SCH2CH2S)] (2), 2-chloro-1,3,2-dithiarsenane [AsCl(SCH2CH2CH2S)] (3), 2-iodo-1,3,2-dithiarsenane [AsI(SCH2CH2CH2S)] (4), 3-chloro-4H,7H-5,6-benz-1,3,2-dithiarsepine [AsCl(SCH2)2(C6H4)] (5), 1,2-bis-dithiarsolan-2-ylmercapto-ethane [As2(SCH2CH2S)2(SCH2CH2S)] (6) and tris-(pentafluorophenylthio)-arsen [As(SC6F5)3] (7). The geometry around As for these compounds is best described as trigonal pyramidal with varying degrees of distortion. Compound 1 crystallizes in two polymorphic forms with similar structural parameters. The compounds have been characterized by IR, 1H, 19F, and 13C NMR, X-ray crystallography and GC–MS.