Condensation Reaction of Dimethyltin(IV) Oxide with 2‐(2,3‐Dichloroanilino)benzoic Acid Synthesis and Study of a Novel Dimeric Tetraorganodistannoxane

The novel symmetric dimeric tetraorganodistannoxane [(Me 2 Sn) 4 (DCPA) 2 )O 2 (OH) 2 ] ( 2 ) and [(Me 2 Sn) 4 (DCPA) 2 )O 2 (OC 2 H 5 ) 2 ] ( 3 ) where HDCPA is 2‐(2,3‐dichloroanilino)benzoic acid ( 1 ) have been prepared. The crystal structure of 3 has been determined by X‐ray crystallography. Three distannoxane rings are present to the centrosymmetric dimeric tetraorganodistannoxane by virtue of μ 3 ‐oxo form the central R 4 Sn 2 O 2 core with a planar Sn 2 O 2 ring, resulting in a ladder type structural motif. Five‐coordinated tin atoms are present in the distannoxane dimer. The ligands act as monodentate agents, thus rendering the tin atom five‐coordinated. Significant π → π stacking interactions and intramolecular hydrogen bonds stabilize the structure 3 . The polar imino hydrogen atom participates in intramolecular hydrogen bonds. The formation of the dimeric distannoxanes 2 and 3 represent a ladder‐type carboxylates in which the insertion of a μ 2 ‐OH or a μ 2 ‐OC 2 H 5 group occurs. This unusual result can be interpreted in terms of a competition between the strength different donors, in which the –OH or the –OC 2 H 5 groups show higher donor capacity than the carboxylato group of DCPA.