Novel mono- and bimetallic organotin() compounds as potential linkers for coordination polymers

The reaction of [2-(O&z.dbd;CH)C 6 H 4 ]Me 2 SnCl ( 2 ), obtained by the hydrolysis of [2-{(CH 2 O) 2 CH}C 6 H 4 ]Me 2 SnCl ( 1 ), with the appropriate diamine, in a 2 : 1 molar ratio, in the absence of a solvent or catalyst, resulted in the bimetallic species ClSnMe 2 [2-C 6 H 4 (4-CH&z.dbd;N-1,1′-C 6 H 4 C 6 H 4 -4′-N&z.dbd;CH)-2′-C 6 H 4 ]Me 2 SnCl ( 4 ) and ClSnMe 2 [2-C 6 H 4 (CH&z.dbd;NCH 2 CH 2 N&z.dbd;CH)-2′-C 6 H 4 ]Me 2 SnCl ( 5 ). The reaction of 2 and 5 with KSCN gave the corresponding isothiocyanates [2-(O&z.dbd;CH)C 6 H 4 ]Me 2 Sn(NCS) ( 3 ) and (SCN)SnMe 2 [2-C 6 H 4 (CH&z.dbd;NCH 2 CH 2 N&z.dbd;CH)-2′-C 6 H 4 ]Me 2 Sn(NCS) ( 6 ). Treating 3 with H 2 NCH 2 CH 2 NH 2 also resulted in the corresponding bimetallic compound 6 . The reaction of 2 with sodium isonicotinate gave [2-(O&z.dbd;CH)C 6 H 4 ]Me 2 SnO(O)CC 5 H 4 N-4 ( 7 ) and the subsequent treatment with ZnTPP (TPP = tetraphenylporphyrinate) led to the isolation of the heterobimetallic complex [{2-(O&z.dbd;CH)C 6 H 4 }Me 2 SnO(O)CC 5 H 4 N-4]ZnTPP ( 8 ). The compounds were characterized by multinuclear NMR spectroscopy and mass spectrometry in solution and IR spectroscopy in the solid state. The molecular structures for compounds 1-6 and 8 were established by single-crystal X-ray diffraction. For all compounds intramolecular O→Sn or N imine →Sn coordination results in hypercoordinated species with a distorted trigonal bipyramidal ( C , E )C 2 SnX core ( E = O, N imine ; X = Cl, N isothiocyanato , O isonicotinato ). In the heterobimetallic complex 8 the zinc atom has a distorted square pyramidal geometry with the N pyridyl atom at the apical position. Organotin( iv ) compounds might be used as linkers for building coordination polymers as suggested by the isolation of [{2-(O&z.dbd;CH)C 6 H 4 }Me 2 SnO(O)CC 5 H 4 N-4]ZnTPP.