MeSi(CH₂SnRO)₃ (R=Ph, Me₃SiCH₂): Building Blocks for Triangular‐Shaped Diorganotin Oxide Macrocycles

Abstract

The syntheses of the novel silicon‐bridged tris(tetraorganotin) compounds MeSi(CH2SnPh2R)3 (2, R=Ph; 5, R=Me3SiCH2) and their halogen‐substituted derivatives MeSi(CH2SnPh(3−n)In)3 (3, n=1; 4, n=2) and MeSi(CH2SnI2R)3 (6, R=Me3SiCH2) are reported. The reaction of compound 4 with di‐t‐butyltin oxide (t‐Bu2SnO)3 gives the oktokaideka‐nuclear (18‐nuclear) molecular diorganotin oxide [MeSi(CH2SnPhO)3]6 (7) while the reaction of 6 with sodium hydroxide, NaOH, provides the trikonta‐nuclear (30‐nuclear) molecular diorganotin oxide [MeSi(CH2SnRO)3]10 (8, R=Me3SiCH2). Both 7 and 8 show belt‐like ladder‐type macrocyclic structures and are by far the biggest molecular diorganotin oxides reported to date. The compounds have been characterized by elemental analyses, electrospray mass spectrometry (ESI‐MS), NMR spectroscopy, 1H DOSY NMR spectroscopy (7), IR spectroscopy (7, 8), and single‐crystal X‐ray diffraction analysis (2, 7, 8).

Dinuclear Organotin Building Blocks and their Conversion into a Tetranuclear Macrocycle Containing Sn−O−Sn Linkages

“…[24,59,[65][66] Interconnection of such organotin tectons through di-or oligotopic ligands such as carboxylates, dithiocarbamates, phosphates, etc., constitutes a pathway to a plethora of metalla-supramolecular assemblies. [65][66] In continuation of previous works, [11,24,59,[65][66][67] herein we report on the formation of two di-nuclear organotin compounds carrying voluminous organic substituents at the metal atoms that were then functionalized with a SnÀ X bond (X = Cl, I). In addition, the potential for the formation of a novel class of tetra-nuclear macrocyclic structures through linkage of the halogenated building blocks by SnÀ OÀ Sn fusion [11,68] was explored.…”

“…[6] Organotin halides are prepared with high yields and purity by selective cleavage of tinÀ carbon bonds through reaction with elemental dihalogens (Cl 2 , Br 2 or I 2 ) or treatment with hydrogen halides. [7] Depending on the identity and number of substituents bound to the tin atom(s) in organotin compounds with diverse inorganic and organic ligands, the formation of specific and frequently complex molecular architectures is accomplished, [8,9] including metalla-macrocycles, [10][11][12][13] cage-type assemblies [14][15][16][17][18] and metal-organic frameworks (MOFs). [19][20][21][22][23] Changes of the substitution pattern at the tin atoms modify the Lewis acidity and steric hindrance, which can be an important requisite for the successful formation of macrocyclic or cage-type structures.…”

“…[19][20][21][22][23] Changes of the substitution pattern at the tin atoms modify the Lewis acidity and steric hindrance, which can be an important requisite for the successful formation of macrocyclic or cage-type structures. [11,[24][25][26][27] Being Lewis acids, four-coordinate tin compounds count on the possibility of coordination number increase, enabling linkages with other compounds, e. g. solvent or guest molecules. [28] Because of these attributes, organotin compounds with interesting properties concerning the catalysis of transesterification and CÀ C coupling reactions, [29][30] anion and molecular recognition, [31][32][33][34][35] materials chemistry, [36][37][38] or biological activity [39][40][41][42] have been developed.…”

“…Recently, promising results have been achieved starting either from tin chalcogenide clusters [16,18,[53][54] or di-or oligonuclear building blocks (tectons) [55][56] containing organic spacers serving as connectors between the metal atoms. [10,11,13,14,17,18,[57][58][59][60][61][62][63][64] An elegant general synthetic methodology towards di-, tri-and tetranuclear building blocks, in which the tin atoms are interconnected by an aliphatic or aromatic organic spacer, consists in the functionalization of organohalides with À Si(CH 3 ) 2 CH 2 Cl substituents followed by derivatization with organotin moieties. [24,59,[65][66] Interconnection of such organotin tectons through di-or oligotopic ligands such as carboxylates, dithiocarbamates, phosphates, etc., constitutes a pathway to a plethora of metalla-supramolecular assemblies.…”

Molecular Cage Assembly by Sn−O−Sn Bridging of Di‐, Tri‐ and Tetranuclear Organotin Tectons: Extending the Spacing in Double Ladder Structures

“…[ 30 , 31 , 32 , 33 ] The fourfold linkage between the inorganic ladders provides robust inorganic‐organic hybrid cages of variable size. [ 42 , 43 ] In addition, there are reports on a double cage based on the trinuclear fragment [{Cl 2 RSn(CH 2 ) 3 } 2 SnCl 2 ] (R=CH 2 SiMe 3 ), [44] on two large macrocyclic assemblies containing belt‐type ladders derived from MeSi(CH 2 SnRI 2 ) 3 (where R=Ph or CH 2 SiMe 3 ), [45a] on a core‐shell type Sn 14 ‐oxo cluster, [45b] on Sn 18 ‐oxo wheel nanoclusters, [45c] high‐nuclearity Sn 26 and Sn 34 ‐oxo clusters, [45d] and a 24‐membered ring containing six triorganotin moieties. [45e] Finally, there is a limited number of publications on polymeric 2D and 3D organotin oxides based on dinuclear building blocks.…”