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 abstractthe synthesis of heteroatom analogues of the cyclopentadienyl anion cp is a fascinating and challenging field of research . 
 the replacement of methine moieties by phosphorus is well investigated for the synthesis of mono , tri and pentaphospholyl ligands . on the other hand , 
 arsenic derivatives are rare and 1,2,4triarsolyl and tetraarsolyl salts are unknown . herein , we report on the synthesis of cs[e3c2(trip)2 ] ( 1  a : e = p ; 1  b : e = as ; trip=2,4,6triisopropylphenyl ) and cs[e4c(trip ) ] ( 2  a : e = p ; 2  b : e = as ) . compound 1  b represents the first 1,2,4triarsolyl and 2  b the first tetraarsolyl anion . 
 all salts are obtained in onepot syntheses using e(sime3)3 , 2,4,6triisopropylbenzoyl chloride and csf . 
 the products 1  a2  c4h8o2 , 2  aet2o and 2  b3  c4h8o2 were characterized by xray structural analysis , which revealed planar heterocycles . 
 nucleusindependent chemical shifts ( nics ) confirmed the aromaticity of these anions . 
 notably , compound 2  aet2o is only the second tetraphospholyl ligand which is structurally characterized . 
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