Assembly of Carbohydrates on a Nickel(II) Center by Utilizing N-Glycosidic Bond Formation with Tris(2-aminoethyl)amine (tren). Syntheses and Characterization of [Ni{N-(aldosyl)-tren}(H
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- 作者：Tomoaki Tanase ; Mayumi Doi ; Reiko Nouchi ; Masako Kato ; Yutaka Sato ; Katsuaki Ishida ; Kimiko Kobayashi ; Tosio Sakurai ; Yasuhiro Yamamoto ; and Shigenobu Yano
- 刊名：Inorganic Chemistry
- 出版年：1996
- 出版时间：August 14, 1996
- 年：1996
- 卷：35
- 期：17
- 页码：4848 - 4857
- 全文大小：606K
- 年卷期：v.35,no.17(August 14, 1996)
- ISSN：1520-510X
文摘
Reactions of[Ni(tren)(H2O)2]X2(tren = tris(2-aminoethyl)amine; X = Cl (1a),Br (1b); X2 = SO4 (1c))withmannose-type aldoses, having a 2,3-cis configuration(D-mannose and L-rhamnose), afforded{bis(N-aldosyl-2-aminoethyl)(2-aminoethyl)amine}nickel(II)complexes,[Ni(N,N'-(aldosyl)2-tren)]X2(aldosyl = D-mannosyl, X= Cl (2a), Br (2b), X2 =SO4 (2c); aldosyl = L-rhamnosyl,X2 = SO4 (3c)). The structureof 1c was confirmedby X-ray crystallography to be a mononuclear[NiIIN4O2] complex with the trenacting as a tetradentate ligand(1c·2H2O: orthorhombic,Pbca, a = 15.988(2) Å, b =18.826(4) Å, c = 10.359(4) Å, V =3118 Å3, Z = 8, R= 0.047, and Rw = 0.042). Complexes2a,c and 3c were characterized byX-ray analyses to have a mononuclearoctahedral Ni(II) structure ligated by a hexadentateN-glycoside ligand,bis(N-aldosyl-2-aminoethyl)(2-aminoethyl)amine (2a·CH3OH: orthorhombic,P212121, a= 16.005(3) Å, b = 20.095(4) Å, c= 8.361(1) Å, V = 2689Å3,Z = 4, R = 0.040, andRw = 0.027.2c·3CH3OH: orthorhombic,P212121, a= 14.93(2) Å, b = 21.823(8) Å,c= 9.746(2) Å, V = 3176 Å3,Z = 4, R = 0.075, andRw = 0.080.3c·3CH3OH: orthorhombic,P212121, a=14.560(4) Å, b = 21.694(5) Å, c =9.786(2) Å, V = 3091 Å3, Z= 4, R = 0.072, and Rw =0.079). The sugarpart of the complex involves novel intramolecular sugar-sugarhydrogen bondings around the metal center. Thesimilar reaction with D-glucose, D-glucosamine,and D-galactosamine, having a 2,3-transconfiguration, resultedin the formation of a mono(sugar) complex,[Ni(N-(aldosyl)-tren)(H2O)2]Cl2(aldosyl = D-glucosyl (4b),2-amino-2-deoxy-D-glucosyl (5a), and2-amino-2-deoxy-D-galactosyl (5b)), instead of abis(sugar) complex. The hydrogenbondings between the sugar moieties as observed in 2 and3 should be responsible for the assembly of twosugarmolecules on the metal center. Reactions oftris(N-aldosyl-2-aminoethyl)amine withnickel(II) salts gave thetris(sugar) complexes,[Ni(N,N',N''-(aldosyl)3-tren)]X2(aldosyl = D-mannosyl, X = Cl (6a), Br(6b); L-rhamnosyl,X = Cl (7a), Br (7b); D-glucosyl, X= Cl (9); maltosyl, X = Br (10); andmelibiosyl, X = Br (11)), which wereassumed to have a shuttle-type C3 symmetricalstructure with 
helical configuration for D-type aldoseson thebasis of circular dichroism and 13C NMR spectra. Whentris(N-rhamnosyl)-tren was reacted withNiSO4·6H2Oat low temperature, a labile neutral complex,[Ni(N,N',N''-(L-rhamnosyl)3-tren)(SO4)](8), was successfully isolatedand characterized by X-ray crystallography, in which three sugarmoieties are anchored only at the N atom of theC-1 position(8·3CH3OH·H2O:orthorhombic, P212121,a = 16.035(4) Å, b = 16.670(7) Å,c = 15.38(1) Å, V= 4111 Å3, Z = 4, R = 0.084,and Rw = 0.068). Complex 8could be regarded as an intermediate species towardthe C3 symmetrical tris(sugar) complexes7, and in fact, it was readily transformed to 7bby an action of BaBr2.
helical configuration for D-type aldoseson thebasis of circular dichroism and 13C NMR spectra. Whentris(N-rhamnosyl)-tren was reacted withNiSO4·6H2Oat low temperature, a labile neutral complex,[Ni(N,N',N''-(L-rhamnosyl)3-tren)(SO4)](8), was successfully isolatedand characterized by X-ray crystallography, in which three sugarmoieties are anchored only at the N atom of theC-1 position(8·3CH3OH·H2O:orthorhombic, P212121,a = 16.035(4) Å, b = 16.670(7) Å,c = 15.38(1) Å, V= 4111 Å3, Z = 4, R = 0.084,and Rw = 0.068). Complex 8could be regarded as an intermediate species towardthe C3 symmetrical tris(sugar) complexes7, and in fact, it was readily transformed to 7bby an action of BaBr2.