The first complete crystal structure of a stannatrane. Trimeric methyl(2,2',2"-nitrilotriethoxy)stannane hexahydrate

Abstract

An X-ray analysis of the 1 -methylstannatrane hexahydrate [MeSnfOCHjCHj^N^-ó^O (4) revealed a trimeric formulation. It crystallizes in the monoclinic space group C2/c (Z = 4) with a = 9.206 (3) Á, b = 13.774 (5) Á, c = 26.581 (4) Á, and ß = 93.33 (2)°. The structure refined to R = 0.074 and Rw = 0.086. The trimeric unit is disordered about a twofold axis, which passes through the central Sn atom. The geometry around this central atom closely approximates a pentagonal bipyramid. The two crystallographically equivalent end tin atoms have distorted-octahedral geometries. Strong association of the three monomeric methylstannatrane units formally leading to the trimer is suggested by the short Sn-0 bond lengths involved. These have values of 2.11 (1) and 2.21 (1) A, as compared to corresponding values within the monomers of 2.17 (1) and 2.23 (1) A, respectively. The solid-state structure agrees with solution NMR data suggesting its retention in solution. The trimeric unit is indicated in solution as is the presence of three nonequivalent tin centers. The structure of 4 is compared with other seven-coordinated tin compounds. The six water molecules of 4 appear hydrogen bonded to each other, forming hexagonal rings that contain inversion centers. Additional hydrogen bonding binds the rings to adjacent molecules of 4.

The First Examples of a Crown Ether Intramolecularly Encapsulating Mono‐ and Diorganotin Dications: Synthesis and Structures of [PhSnCH2([16]crown‐5)][ClO4]2 and [HOSnCH2([16]crown‐5)][Y]2 (Y=ClO4, CF3SO3)

“…Both values are low‐frequency shifted and the first one falls in the range of the heptacoordinated diorganotin compound [(Bu 2 Sn) 3 O(Hpurpurine) 2 ] ( δ =−416 ppm)82 with a SnC 2 O 5 substituent pattern and of R 2 Sn(dib) (R=Me, δ =−437 ppm; R= n Bu, δ =−441 ppm; dib=dianion of diacetylpyridine bis(benzoyl)hydrazone)83 with a SnC 2 O 2 N 3 substituent pattern. The second one is even more low‐frequency shifted and close to the chemical shifts of δ =−537 and −561 ppm reported for the heptacoordinated tin atoms in trimeric [MeSn(OC 2 H 4 ) 3 N] 3 84–86 (SnCO 5 N substituent pattern) and n BuSn(Oxinate) 3 87 (SnCO 3 N 3 substituent pattern), respectively. To the best of our knowledge, we are not aware of a heptacoordinated organotin compound with a SnCO 6 substituent pattern.…”

“…in trimeric [MeSnA C H T U N G T R E N N U N G (OC 2 H 4 ) 3 N] 3[84][85][86] (SnCO 5 N substituent pattern) and nBuSnA C H T U N G T R E N N U N G (Oxinate) 3[87] (SnCO 3 N 3 substituent pattern), respectively. To the best of our knowledge, we are not aware of a heptacoordinated organotin compound with a SnCO 6 substituent pattern.…”

The synthesis and crystal structure of the first metal-bound stannatrane complex Os(Sn[OCH2CH2]3N)(η2-S2CNMe2)(CO)(PPh3)2: structural comparisons with the analogous silatrane complex Os(Si[OCH2CH2]3N)(η2-S2CNMe2)(CO)(PPh3)2

“…7,8 In contrast to silatranes, reports of the analogous tin compounds, stannatranes, are sparse, with only two crystallographically characterised examples. 9,10 Our recent work has focused on the synthesis of trihalostannyl osmium complexes because these complexes are amenable to further derivatisation at the tin centre. Here, we report the synthesis and structural characterisation of the first metal-substituted stannatrane, Os(Sn[OCH 2 CH 2 ] 3 N)(h 2 -S 2 CNMe 2 )(CO)(PPh 3 ) 2 , which is formed by a ligand reaction of the triiodostannyl osmium complex, Os(SnI 3 )(h 2 -S 2 CNMe 2 )(CO)(PPh 3 ) 2 , with triethanolamine.…”

Diverse Molecular Architectures of Si and Sn [4.4.3.01,6]Tridecane Cages Derived from a Mannich Base Possessing Semi‐Rigid Unsymmetrical Podands

“…In addition, self-association in stannatranes is very likely and is responsible for the formation of bridged tricyclic cages through Sn-O-Sn bridges. [9,53,54] In the present work, Si and Sn [4.4.3.0]tridecane cages 1-3 have been derived from a semi-rigid Mannich base ligand, N,N-bis(2-hydroxy-3,5-dimethylbenzyl)-2-aminoethanol (H 3 L), with unsymmetrical podands. The flexibility of this ligand provides the opportunity for the hypercoordination of Sn through (ladderlike) Sn-O-Sn bridges, thus resulting in the self-assembly of these tricyclic tin cages.…”