The effect of substituents of the 1,10-phenanthroline ligand on the nature of diorgnotin(IV) complexes formation

•Six new diorgnotin(IV) complexes have been synthesized and fully characterized.•The effect of phenanthroline substituents on the nature of complex is investigated.•The reaction of R2Sn(NCS)2 with phenanthroline led to the formation of adducts.•Organotin salt produced in reaction of dimethylphenanthroline with (CH3)2Sn(NCS)2.

The adduct formation between dimethyl- and dibuthyltin diisothiocyanate and 1,10-phenanthroline and 2,9-dimethyl-1,10-phenanthroline were investigated. It was found that the reaction of R2Sn(NCS)2 (R = Me, n-Bu) with 1,10-phenanthroline in a 1:1 M ratio led to the formation of simple adducts of [Me2Sn(NCS)2(phen)]·CH3CN (1) and [Bu2Sn(NCS)2(phen)] (2), for R = Me and R = n-Bu, respectively. However, the reaction of 2,9-dimethyl-1,10-phenanthroline with R2Sn(NCS)2 (R = Me, n-Bu), instead of adducts, resulted in the formation of an organostannate salt, (C14H13N2)2[Me2Sn(NCS)4] (3), and dimeric stannoxane, [Me2(NCS)SnOSnMe2OCH3]2 (4), for R = Me and (C14H13N2)NCS (5), and [Bu2(NCS)SnOSnR2OBu]2 (6), for R = n-Bu. Single crystal X-ray structural analyses were carried out for complexes 1, 3, 4, and 5. The crystal structures results of 1, 3, 4, and 5 along with the 1H, 13C and 119Sn NMR and IR spectroscopic measurements of all the products are used to discuss the effect of the substituent of 1,10-phenanthroline on complex formation. The results show that the central tin atom of the stannate salt (3) is not bonded to the two N donor atoms of the ligand species, and the moderately bulky substituent at the 2 and 9 positions of 1,10-phenanthroline ligand exerts a profound influence on the nature of the complexes and their formation.

Graphical abstractThe reaction of R2Sn(NCS)2with 1,10-phenanthroline led to the formation of simple adduct, and the reaction of 2,9-dimethyl-1,10-phenanthroline with R2Sn(NCS)2 (R = Me, n-Bu), instead of adducts, resulted in the formation of an organostannate salt, (C14H13N2)2[Me2Sn(NCS)4], and [Me2(NCS)SnOSnMe2OCH3]2, for R = Me and (C14H13N2)NCS and [Bu2(NCS)SnOSnR2OBu]2 for R = n-Bu.Figure optionsDownload full-size imageDownload as PowerPoint slide