Addukte schwefelhaltiger Heteroaromaten mit SbCl3 Untersuchungen zur Bildung und Kristallstruktur von 2,2′-Dithienyl · 2 SbCl3 und Benzo[b]thiophen · 2 SbCl3

Adducts of Sulfur-containing Hetero Aromates with SbCl₃: Studies on Formation and Crystal Structure of 2,2′-Dithienyl · 2 SbCl₃ and Benzo[b]thiophene · 2 SbCl₃ Whereas the system 2,2′-dithienyl—SbCl₃ because of irreversible thermal decomposition reactions could not be studied by DTA, this method applied to the system benzo[b]thiophene—SbCl₃ yielded a quasibinary behaviour and the existence of a compound benzo[b]thiophene · 2SbCl_3. melting congruently at 71.2°C. Crystals of this adduct and that of analogue composition 2,2′-dithienyl · 2SbCl₃ were obtained from solution. Their structures were determined by X-ray diffraction as those of bπ-v complexes. They are compared with other Menshutkin complexes. The π…?Sb interactions are indicated by distances between the planes of the planar hetero aromates and the Sb atoms located in a transoid way above both single rings of 316 (dithienyl adduct) and 325 pm (benzothiophene adduct). There is no particular coordinative bond formation by the S atoms. The intermolecular linking in the SbCl₃ partial structures is described.