Subvalent Group 4B metal alkyls and amides. Part 9. Germanium and tin alkene analogues, the dimetallenes M₂R₄[M = Ge or Sn, R = CH(SiMe₃)₂]: X-ray structures, molecular orbital calculations for M₂H₄, and trends in the series M₂R′₄[M = C, Si, Ge, or Sn; R′= R, Ph, C₆H₂Me₃-2,4,6, or C₆H₃Et₂-2,6]

Synthesis, Characterization and Real Molecule DFT Calculations for Neutral Organogallium(I) Aryl Dimers and Monomers: Weakness of GalliumGallium Bonds in Digallenes and Digallynes

“…Complexes 7 and 8 dissociate to monomers in hydrocarbon solution and their electronic spectra closely resemble those of 10 and 11 as well as those of [Ar' GaGaAr'] (Ar' = C 6 H 3 -2,6(C 6 H 3 -2,6-iPr 3 ) 2 ) and [(GaAr*) n ] (Ar*= C 6 H 3 -2,6(C 6 H 2 -2,4,6-iPr 3 ) 2 ). The calculations showed that the binding energies of the compounds are weak, resemble closedshell interactions and average % 5 kcal mol…”

“…The synthesis [1] and structural characterization [2] of the di-A C H T U N G T R E N N U N G stannene [R 2 SnSnR 2 ] (R= CHA C H T U N G T R E N N U N G (SiMe 3 ) 2 ) in the 1970 s was a watershed event for the study of multiple bonding between main group elements. The tin pyramidal coordination observed and the lack of significant tin À tin bond shortening relative to a single bond were in sharp contrast to the planar structure of its carbon based alkene analogues, which have much shorter C=C bonds.…”

Reactions of bis[bis(trimethylsilyl)methyl]germylene and the corresponding stannylene with diazidosilanes

“…ble by reactions of silylenes (R2Si:), germylenes (R2Ge:), and stannylenes (R,Sn:) with azides (Equation 1). In a recent article [4,5], we reported preparation of N-(azidosily1)germanimines by conversion of bis[bis(trimethylsilyl)methyl]germylene (1) [6] with di-tert-butyl-and dimesityldiazidosilane and reactions of 1 with dimethyl-and diphenyldiazidosilane. Herein, we wish to report the synthesis and structural features of the stable N -(azidosily1)stannanimine (5) which was obtained by treatment of the corresponding stannylene (2) with di-tert-butyldiazidosilane (3) and also the corresponding N-(azidosily1)germanimine (4) prepared and studied in an analogous manner.…”

Parent Heavy Methylenes: Chemical Tricks to Access Isolable Complexes of Elusive H2E: Species (E=Ge and Sn)

“…However, the introduction of sterically congesting substituents at the metal centers can bring about higher kinetic stabilization of the E = E bonds, which has led to the astonishingly facile isolation of stable disilenes, digermenes, and distannes. [2][3][4] Moreover, the latter groundbreaking work by Lappert et al [4] has stimulated the synthesis of a vast number of isolable dimetallenes, including an air-stable disilene, which was reported recently by Tamao and coworkers.…”