- Synthesis of a chiral rod-like metal–organic framework from a preformed amino acid-based hexanuclear wheel
-
We report the two-step synthesis of a chiral rod-like metal-organic framework (MOF). The chemical approach consists on the use of a previously prepared oxamato-based homochiral hexanuclear wheel, the ligand being a derivative of the natural amino acid l-alanine, with formula (Me4N)6{CuII6[(S)-alama])6}·10H2O (1) [where (S)-alama=(S)-N-(ethyl oxoacetate)alanine]. The anionic hexacopper(II) wheels, stabilized by the presence of templating tetramethylammonium counter-cations, disassemble in the presence of cationic square-planar [Ni(cyclam)]2+ complexes to yield, after a supramolecular reorganization process that involves axial coordination of the [Ni(cyclam)]2+ cations through the free carbonyl groups of the copper(II) moieties, a neutral chiral rod-like, three-dimensional (3D) MOF with formula [Ni(cyclam)][Cu(S)-alama]2·16H2O (2). The resulting MOF constitutes one of the few examples where such a high-nuclearity metal complex is used as precursor for the construction of rod-like MOFs.
- Grancha,Ferrando-Soria,Armentano,Pardo
-
p. 1204 - 1221
(2019/07/03)
-
- PROCESS FOR THE MANUFACTURE OF N-ALKOXALYL-ALANINATES
-
A process for the manufacture of alkyl N-alkoxalyl-alaninates of the formula alkylO-CO-CO-NH-CH(CH3)-CO-Oalkyl comprises reacting alanine with a dialkyl oxalate under substantially non-acidic conditions, which may be created by carrying out the reaction in the presence of a base. The reaction may furthermore be carried out in the presence of added alkanol, preferably one featuring the alkyl group corresponding to that of the employed dialkyl oxalate. The monoesters N-alkoxalyl-alanine of the formula alkylO-CO-CO-NH-CH(CH3)-COOH, which as intermediates in the process can be isolated therefrom, are novel and as such are also an object of the present invention. The alkyl N-alkoxalyl-alaninates are useful intermediates in the multistep process for the manufacture of vitamin B6.
- -
-
-