Novel Trialkanolamine Derivatives of Tin of the Type [N(CH₂CMe₂O)₂(CH₂)_nOSnOR]_m (m = 1, 2; n = 2, 3; R = t-Bu, 2,6-Me₂C₆H₃) and Related Tri- and Pentanuclear Tin(IV) Oxoclusters. Syntheses and Molecular Structures

Abstract

The syntheses of the novel alkanolamine N(CH(2)CMe(2)OH)(2)(CH(2)CH(2)CH(2)OH) (2), the novel aminotrialkoxides of tin of the type [N(CH(2)CMe(2)O)(2)(CH(2))(n)OSnOR](m) (3: m = 1, n = 2, R = t-Bu; 4: m = 2, n = 3, R = t-Bu; 5: m = n = 2, R = 2,6-Me(2)C(6)H(3); 6: m = 2, n = 3, R = 2,6-Me(2)C(6)H(3)) and the related trinuclear tin oxoclusters [(LSnOSnL)(LSnOR)] [L = N(CH(2)CMe(2)O)(2)(CH(2)CH(2)O), 7: R = t-Bu; 8: R = 2,6-Me(2)C(6)H(3)] and the pentanuclear tin oxocluster [LSnOSn(OH)(2)OSnL·2LSnOH], [9, L = N(CH(2)CMe(2)O)(2)(CH(2)CH(2)O)] are reported. The compounds are characterized by elemental analyses, multinuclear ((1)H, (13)C, (119)Sn, (1)H-(1)H cosy, (1)H-(13)C HSQC) NMR spectroscopy, electrospray ionization mass spectrometry, and single crystal X-ray diffraction analyses (3, 4·C(7)H(8), 5, 7, 8·0.5C(7)H(8), 9·6H(2)O).

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

“…The N1-Sn1 and N2-Sn2 distances in this dimeric pseudo-stannatrane (2) are 2.256(2) and 2.276(1) Å. These N-Sn distances are shorter than those in dimeric 1-alkoxido-stannatranes [9] [N(CH 2 CMe 2 O) 2 [9] [N(CH 2 CMe 2 O) 2 [63] [ Compound 3 is a centrosymmetric dimer consisting of a planar ladder-like Sn 4 O 4 unit in the form of three fused four-membered cyclic cores (Figure 3). The endo Sn2-O4-Sn2*-O4* core and the exo Sn1-O3-Sn2-O4 and Sn1*-O3*-Sn2*-O4* cores are basically planar with a maximum deviation of 2.20(6)°(see Figure S4 in the Supporting Information).…”

“…The dimeric 1-alkoxido-stannatranes [9] [N(CH [9] [N(CH 2 CMe 2 O) 2 remains in the Sn 2 O 2 plane, whereas the other occupies a site perpendicular to this plane. Consequently, the distribution of donor sets in the two units is not symmetrical (see Figure S3 in the Supporting Information).…”

“…[7] However, there are very few reports on the Si and Sn coordination chemistry of related ligands with the formation of unsymmetrical [4.4.3.0]tridecane and [4.3.3.0]dodecane cages. [8,9] In addition, bis-phenol amines with a flexible neutral donor arm remain at the forefront of research efforts on metal alkoxide systems for catalysing the polymerization of cyclic esters and alkenes, oxidation reactions, C-C cross-coupling reactions and as molecular models for biological systems. [10][11][12][13][14][15][16][17] The Mannich base condensation of ethanolamine and 2,4-disubstituted phenols produces phenolic amines with unsym-NMR, FTIR and MS).…”

“…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.…”

Carbastannatranes: a powerful coupling mediators in Stille coupling

“…[53][54][55][56][57] Amongst different organotin cyclic systems, stannatranes possess cage like structures with transannular donoracceptor interaction. 59,60,[62][63][64][65][66][67][68] Tin-atranes possessing heteroatoms like oxygen (stannatranes), nitrogen (azastannatranes) and sulphur (thiastannatranes) at the equatorial donor site have not been reported as coupling mediators. Depending upon the equatorial donor atoms (Y), they are categorized into stannatranes, carbastannatranes, azastannatranes and thiastannatranes (Chart 1).…”