An unusual trigonal-bipyramidal coordination of gallium by an aza crown ether. Synthesis and molecular structure of [Ga(CH3)2][C12H25N2O4][Ga(CH3)3]2

1990 ◽  
Vol 9 (6) ◽  
pp. 1709-1711 ◽  
Author(s):  
Baosheng Lee ◽  
William T. Pennington ◽  
Gregory H. Robinson
Keyword(s):  
Molecular Structure ◽  
Crown Ether ◽  
Trigonal Bipyramidal Coordination ◽  
Trigonal Bipyramidal ◽  
Ether Synthesis ◽  
Aza Crown Ether

Studies on a selena-aza-crown ether: Synthesis and catalytic behavior in hydrosilylation

1997 ◽  
Vol 2 (4) ◽  
pp. 464-466 ◽  
Author(s):  
Xu Wei ◽  
Liu Xiufang ◽  
Lu Xueran ◽  
Xu Hansheng
Keyword(s):  
Crown Ether ◽  
Catalytic Behavior ◽  
Ether Synthesis ◽  
Aza Crown Ether

scholarly journals Di-μ-chlorido-bis[aquachloridodimethyltin(IV)]–1,4,7,10,13-pentaoxacyclopentadecane (1/1)

2012 ◽  
Vol 68 (4) ◽  
pp. m354-m354 ◽  
Author(s):  
Mostafa M. Amini ◽  
Seik Weng Ng
Keyword(s):  
Crown Ether ◽  
Metal Atom ◽  
Title Compound ◽  
Outer Sphere ◽  
Water Molecules ◽  
Site Symmetry ◽  
Special Position ◽  
Trigonal Bipyramidal Coordination ◽  
Trigonal Bipyramidal ◽  
Coordinated Water

The Sn, Cl and water O atoms of the title compound, [Sn2(CH3)4Cl4(H2O)2]·C10H20O5, lie on a special position of 2 site symmetry. The SnIVatom showscis-C2SnCl2O trigonal–bipyramidal coordination [C—Sn—C = 157.0 (1)°]; however, two [Me2SnCl2(H2O)] units are linked by a tin–chlorine bridge [Sn←Cl = 3.247 (1) Å] across a center of inversion, generating a dinuclear species, so that the geometry is better regarded as amer-C2SnCl3O octahedron. The crown ether interacts through O—H...O hydrogen with the metal atom through the coordinated water molecules in an outer-sphere manner, generating a hydrogen-bonded chain running along [101]. The 15-crown-5 molecule is disordered over the 2/msite.

Synthesis, Structures and Reactions of Trimethyltantalum(V) Bis[tri(tert.-butyl)silanolate]

2011 ◽  
Vol 66 (4) ◽  
pp. 392-396
Author(s):  
Jörg Knizek ◽  
Heinrich Nöth
Keyword(s):  
Molecular Structure ◽  
Equatorial Plane ◽  
Tert Butyl ◽  
Trigonal Bipyramidal Coordination ◽  
Trigonal Bipyramidal

Bis[tri(tert.-butyl)silanolato]tantalum(V) trichloride reacts with LiMe to give trimethyl-bis[tri- (tert.-butyl)silanolato]tantalum(V), 6. Its molecular structure shows a trigonal-bipyramidal coordination of the Ta atom with the Me groups in the equatorial plane. Its reaction with catecholborane produces preferably B-methyl-catecholborane besides some phenylene-1,2-dioxo-bis(1,3,2-dioxaborolane), 9, and H3 B・ THF. Similarly, the reaction of 6 with dimeric 9-borabicyclononane (9-BBN) generates preferable tri(tert.-butyl)siloxy-9-BBN (75%) and Me-9-BBN (25%). In contrast, cleavage of the Ta-O bonds is the preferred route in the treatment of 6 with H3B ・ THF. 11B NMR shows the formation of (tBu3SiO)2BH and (tBu3SiO)3B or (tBuSiO)3B3O3. No tantalum hydride could be isolated.

On the structural diversity anions coordinate to the butterfly-shaped [(R2Sn)3O(OH)2]2+ cations and vice versa

2014 ◽  
Vol 92 (6) ◽  
pp. 496-507 ◽  
Author(s):  
Hans Reuter ◽  
Hilko Wilberts
Keyword(s):  
Hydrogen Bonds ◽  
Iodine Atom ◽  
Structural Parameters ◽  
Structural Diversity ◽  
Hydroxyl Groups ◽  
Equatorial Position ◽  
Chelating Ligands ◽  
Trigonal Bipyramidal Coordination ◽  
Trigonal Bipyramidal ◽  
Oxygen Framework

The syntheses and crystal structures of [(t-Bu2Sn)3O(OH)2]CO3·3MeOH, 1a, [(t-Bu2Sn)3O(OH)2]CO3·3H2O·acetone, 1b, [(t-Bu2Sn)3O(OH)2][I]2·[(t-Bu2Sn(OH)I]2·2DMSO, 1c, and [(Cy2Sn)3O(OH)2][I]2·2DMSO, 2a, all containing the trinuclear [(R2Sn)3O(OH)2]2+ ion have been described. The butterfly shape of this cation is derived from two annulated, four-membered tin–oxygen rings with a central μ3-oxygen atom and trigonal-bipyramidally coordinated tin atom both belonging to both rings and two μ2-hydroxyl groups and two outer, four-fold coordinated tin atoms. In 1a and 1b, the carbonate anions interact with the outer tin atoms of the cations as bidentate chelating ligands in the classical syn–syn coordination mode, and vice versa. In this way, both outer tin atoms expand their coordination sphere from four to five, with the consequence that bond angles and lengths within the cation are determined by the axial and equatorial position of the oxygen atoms within the trigonal-bipyramidal coordination on all three tin atoms. 1c consists of two different building units, an up to now unknown hydroxide iodide of composition [(t-Bu2Sn(OH)I]2 with hydrogen-bonded DMSO molecules and a [(t-Bu2Sn)3O(OH)2]2+ cation with one coordinated and one isolated, via hydrogen bonds connected iodine ion. The hydroxide iodine is built up of two five-fold coordinated tin atoms linked via two hydroxyl groups with exocyclic iodine atoms occupying axial positions at the trigonal-biypramidally coordinated tin atoms. The unprecedented coordination of the iodine ion to the [(t-Bu2Sn)3O(OH)2]2+ cation takes place between both outer tin atoms, resulting in a five-fold, trigonal-bipyramidal coordination at these tin atoms, too. Structural parameters within the so-formed [(t-Bu2Sn)3O(OH)2I]+ complex are very similar to those of 1a and 1b, with the exception of a significant lengthening of the tin–oxygen bonds opposite to the bridging iodine atom. 2a represents the first example of the [(R2Sn)3O(OH)2]2+ cation without R = t-butyl, so far. In the solid, it consists of two crystallographic independent [(Cy2Sn)3O(OH)2][I]2 building units, each connected to two DMSO molecules via hydrogen bonds. Both building units are very similar with respect to their conformation. Each of the iodine anions coordinates with only one of the two outer tin atoms, one in an inwards, one in an outwards to the tin-oxygen framework directed position. These tin atoms are therefore also trigonal-bipyramidally coordinated as in 1a−1c, but because of steric reasons one of the trigonal-bipyramids has changed its orientation within the tin–oxygen framework, accompanied by enormous changes of bond lengths and angles therein.

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