Isolation and characterization of [n-Bu2Sn(OH2)(phen)(OSO2CF3)](O3SCF3) (phen = 1,10-phenanthroline): The missing link

• The study of the reactivity of Bu 2 Sn( μ -OH)(H 2 O)(OSO 2 CF 3 )] 2 ( 1 ) with 1,10 - phenanthroline (phen) was continued in order to complete the identification of the organotin(IV) species involved. • A novel 1,10-phenanthroline derivative of diorganotin(IV) trifluoromethanesulfonate characterized as [ n -Bu 2 Sn(OH 2 )(Phen)(OSO 2 CF 3 )](O 3 SCF 3 ) (4) has been isolated. • The structure of 4 established by XRD on single crystal consists of a mononcationic di- n -butyltin(IV) complex, N,N -chelated by one phen ligand and coordinated by one water molecule and one trifluoromethanesulfonato ligand. • Further additions of phen to a solution of 4 lead to the formation of [ n -Bu 2 Sn( μ -OH)(phen)] 2 (O 3 SCF 3 ) 2 ( 5 ) and [ n -Bu 2 Sn(phen) 2 ](O 3 SCF 3 ) 2 ( 6 ). • Complex 4 can be regarded as a reaction intermediate and considered as the missing link connecting 1 to 5 and 6 . Reaction of [ n -Bu 2 Sn( μ -OH)(H 2 O)(OSO 2 CF 3 )] 2 ( 1 ) with 1,10-phenanthroline (phen) in acetonitrile at room temperature in a 1:0.75 molar ratio leads to the formation of a mixture of three species comprising [{ n -Bu 2 Sn(H 2 O)} 2 O· n -Bu 2 Sn(OH) 2 ](O 3 SCF 3 ) 2 ( 2 ) and [{ n -Bu 2 Sn(OH)(OSO 2 CF 3 )}( n -Bu 2 SnO)] 2 ( 3 ) as well as the title compound [ n -Bu 2 Sn(OH 2 )(phen)(OSO 2 CF 3 )](O 3 SCF 3 ) ( 4 ). Compounds 1, 2 and 3 crystallize in dichloromethane at –20°C, while 4 remains in solution under these conditions. After filtration and by repeating this procedure several times (four in total), it was possible to isolate only 4 . Single-crystals of 4 , suitable for an X-ray diffraction analysis, were grown from a mixture of dichloromethane/toluene. Compound 4 consists of a mononcationic di- n -butyltin(IV) complex, N,N -chelated by one phen ligand and coordinated by one water molecule and one trifluoromethanesulfonato ligand. In the crystal lattice, the individual molecule of 4 are associated in dimers resulting from intermolecular hydrogen-bonding interactions between aqua ligands and trifluoromethasulfonate counteranions. The isolation and characterization of compound 4 provides new insights into the reactivity of 1 with phen.