Substituent-dependent exchange mechanisms in highly fluxional RSn93− anions

Abstract

119Sn NMR studies show that the RSn9(3-) ions (R=i-Pr, Sn(C6H11)3) are highly fluxional in solution, where the exchange mechanisms involve rapid migration of the R group in the latter but not in the former.

Shuttling P3 from Niobium to Rhodium: The Synthesis and Use of Ph3SnP3(C6H8) as a P3− Synthon

“…This sharp singlet is indicative of whizzing of the Ph 3 Sn moiety about the cyclo-P 3 ring. 1,[10][11][12] Variable temperature NMR spectra obtained as low as −90 • C reveal no locking out of this movement on the NMR time scale.…”

Reactions of exo‐Substituted RSn93− Clusters with Pd: Endohedral Cluster Formation and Oxidative Insertion

“…[23] NMR studies: As previously reported, [38] (Table 3). While the solid-state structure shows that the SnCy 3 exo group is attached to the upper waist of a distorted C 4v -type cluster (Scheme 1), the SnCy 3 moiety does an intramolecular walk around the Sn 9 cluster in solution, while the Sn 9 cluster simultaneously undergoes a diamond-square-diamond exchange that time-averages all nine vertex atoms.…”

“…[26][27][28][29][30][31][32] In particular, the [ 3À clusters, wherein R is an exo-bonded alkyl or posttransition metal group, have been prepared by nucleophilic substitution reactions. [33][34][35][36][37][38] Unlike the multicenter two-electron bonding within the E 9 clusters, the exo substituents are attached to the clusters through two-center, two-electron bonds. The substituents are known to affect the solubilities [25,35] and dynamic properties of the clusters, [38] but the reactivities of these ions have not been studied in detail.…”

“…[33][34][35][36][37][38] Unlike the multicenter two-electron bonding within the E 9 clusters, the exo substituents are attached to the clusters through two-center, two-electron bonds. The substituents are known to affect the solubilities [25,35] and dynamic properties of the clusters, [38] but the reactivities of these ions have not been studied in detail. [33,39] We report here the reaction of [Sn 9 SnCy 3 ] 3À (1) with [Pd-A C H T U N G T R E N N U N G (PPh 3 ) 4 ], which leads to sequential inclusion and oxidative insertion of two Pd atoms to produce [Pd@Sn 9 SnCy 3 ] 3À (2) and [Pd@Sn 9 PdSnCy 3 ] 3À (3), respectively.…”

Synthesis of Nine-atom Deltahedral Zintl Ions of Germanium and their Functionalization with Organic Groups

“…[3][4][5][6] Notable milestones are the oxidative coupling of Ge9 4-clusters to oligomers and infinite chains, 7-19 their metallation, [14][15][16][20][21][22][23][24][25] capping by transition-metal organometallic fragments, 26-34 insertion of a transition-metal atom at the center of the cluster which is sometimes combined with capping and oligomerization, 35-47 addition of main-group organometallic fragments as exo-bonded substituents, 48-50 and functionalization with various organic residues by reactions with organic halides and alkynes. [51][52][53][54][55][56][57][58] This latter development of attaching organic fragments directly to the clusters has opened up a new field, namely organo-Zintl chemistry, that is potentially fertile for further synthetic explorations, and it is the step-by-step procedure for the synthesis of germanium-divinyl clusters described herein. The initial steps outline the synthesis of an intermetallic precursor of K4Ge9 from which the Ge9 4-clusters are extracted later in solution.…”