A number of stannylene complexes with different M: Sn ratios were obtained using various metals and substituents at the tin atom. The structures of the complexes were examined. A reaction of CpMn(CO)₂THF with (Ph₄As)⁺(SnCl₃)⁻ gave the ionic complex [Ph₄As]⁺[CpMn(CO)₂SnCl₃]⁻ (I). The action of C₆F₅MgBr on the complex C₅H₅Mn(CO)(NO)SnCl₃ produced C₅H₅Mn(CO)(NO)Sn(C₆F₅)₃ (II). Replacement of the Cl ions in the complex [CpFe(CO)₂]₂SnCl₂ by phenylacetylenide groups gave rise to the neutral complex [CpFe(CO)₂]₂Sn(C≡CPh)₂ (III). A reaction of (Dppm)PtCl₂ (Dppm is 1,1-bis(diphenylphosphino)methane) with SnCl₂ · 2H₂O in the presence of diglyme yielded the ionic complex [η³-CH₃O(CH₂)₂O(CH₂)₂OCH₃)SnCl]⁺[(η ²-Dppm)Pt(SnCl₃)₃]⁻ (IV). Transmetalation in a reaction of [(Dppe)₂CoCl][SnCl₃] · PhBr (Dppe is 1,2-bis(diphenylphosphino)ethane) with (Dcpd)PtCl₂ (Dcpd is dicyclopentadiene) in the presence of SnCl₂ afforded the ionic complex [Pt(Dppe)₂]₃[Pt(SnCl₃)₅]₂ (V). Structures I–V were identified by X-ray diffraction. In these structures, the formally single bonds between the atoms of transition metals M (Mn, Fe, and Pt) and Main Group heavy elements (Sn and P) having vacant d orbitals are appreciably shortened. The M-Sn bond length in complexes II and III are virtually independent of the substituents at the tin atom and the Pt-Sn bond length in complexes IV and V is virtually independent of the Pt: Sn ratio.

Reactions of cymantrenecarboxylic acid (CO)₃MnC₅H₄COOH (CymCOOH) with Ni(II) and Co(II) pivalates in boiling THF followed by extraction of the products with diethyl ether or benzene and treatment with triphenylphosphine gave the binuclear complexes LM(CymCOO)₄ML (M = Ni (I) and Co (II); L = PPh₃). Treatment of the benzene extract of the intermediate cobalt cymantrenecarboxylate with 2,6-lutidine (L’) yielded the trinuclear complex L’Co(CymCOO)₃Co(CymCOO)₃CoL’ (III). Complex I is antiferromagnetic; μ_eff decreases from 3.7 to 0.9 μ_B in a temperature range from 300 to 2 K. Structures I-III were identified using X-ray diffraction. The frameworks of complexes I and II are like Chinese lanterns, having four carboxylate bridges and axial ligands L (Ni-P, 2.358(1) Å; Co-P, 2.412(2) Å). The metal atoms are not bonded to each other (Ni…Ni, 2.7583(9) Å; Co…Co, 2808 (2) Å). In complex III, either terminal Co atom is coordinated to one ligand L’ (Co-N, 2.059(2) Å). The Co atoms form a linear chain showing no M-M bonds (Co…Co, 3.346(1) Å), in which either terminal Co atom is linked with the central Co atom by three carboxylate bridges (on average, Co_centr-O, 2.164 Å; CO_term-O, 2.094 Å). In one of three carboxylate groups, only one carboxylate O atom serves as a bridge, while the other is bonded to the terminal Co atom only (Co_term-O, 2.094 and 2.389 Å); so this carboxylate group is a bridging and chelating ligand.