A C3-chiral lithium triamidostannate(II) containing a SnLi bond

Reactions of Phenyllithium with the Stannylene Ar*SnPh (Ar* = C6H3-2,6-Trip2; Trip = C6H2-2,4,6-Pri3) and the Synthesis of the Distannylstannylene Sn(SnPh2Ar*)2: Contrasting Behavior in Methyl and Phenyl Derivatives

“…A partial X-ray crystal structure, which was marred by severe disorder problems in the LiSnPh 2 Ar* moiety and the solvating ether, showed that lithium was coordinated to tin, to an aryl ring in an η 6 -fashion, and to an ether oxygen. The Li−Sn contact is approximately 2.78 Å long, which may be compared to the longer distances of 2.871(7) Å in Li(PMDETA)SnPh 3 , 2.89(4) Å in (THF) 3 LiSn{N(SiMe 3 ) 2 CH 2 } 3 CH 3 , 2.93(5) Å in (THF) 3 Li{N(p-Tol)SiMe 2 } 3 CH, and 3.06(2) Å in (THF) 3 LiSn{N(1-naphthyl)SiMe 2 } 3 CH . It seems likely that the Li−Sn distance in 1 is shorter than those in the Lewis base-complexed molecules because the complexation of lithium by three Lewis base atoms is probably a more effective coordination array than the single Lewis base and an η 6 -aryl coordination in 1 .…”

“…The Li-Sn contact is approximately 2.78 Å long, which may be compared to the longer distances of 2.871(7) Å in Li(PMDETA)SnPh 3 , 9 2.89(4) Å in (THF) 3 LiSn{N(SiMe 3 ) 2 CH 2 } 3 CH 3 , 10 2.93(5) Å in (THF) 3 Li{N(p-Tol)SiMe 2 } 3 CH, 10 and 3.06(2) Å in (THF) 3 -LiSn{N(1-naphthyl)SiMe 2 } 3 CH. 11 It seems likely that the Li-Sn distance in 1 is shorter than those in the Lewis base-complexed molecules because the complexation of lithium by three Lewis base atoms is probably a more effective coordination array than the single Lewis base and an η 6 -aryl coordination in 1. In contrast there is an extremely short Li-Sn distance of 2.685(8) Å in the methyl-substituted species LiAr*MeSnSn-Me 2 Ar* 2 , which is probably due to the chelating action of a flanking aryl ring of the Ar* ligand The latter also possesses a large 7 Li-119 Sn coupling of 736 Hz, whereas 1 has a corresponding value of 580 Hz.…”

Syntheses and Structural Characterization of the Heavier Alkali-Metal Stannates Bearing the Tripodal Triamino Framework: Structural Trends in the Series of [MeSi{SiMe2N(4-CH3C6H4)}3Sn][M] (M = Na, K, Rb)

“…We recently began to study the structural details of anionic tripodal triaminostannates(II) and their use as “ligands” in transition-metal chemistry. − In this paper, we report the synthesis and structural characterization of a novel trisilylsilane-derived hexaaminodistannane and its conversion by reductive cleavage to the corresponding heavier alkali-metal (sodium, potassium, rubidium) stannates(II). This allowed us to conduct a systematic, comparative structural study of the interactions between the group 1 cations and the stannate cages.…”