Chiral metal-organic framework

Falkowski JM, Liu S, Lin W. Asymmetric catalysis with chiral metal organic frameworks. In Llabres i Xamena FX, Gascon J, editors. Metal organic frameworks as heterogeneous catalysts. Cambridge The Royal Society of Chemistry 2013. p. 344-64. 

Meio-epoxides undergo a ring-opening reaction with aromatic amines in the presence of a chiral metal-organic framework catalyst Zn2(L)(H20)2(A,A -dimethylacetamide)4 where L, [(S)-6,6 -dichloro-2,2 -diethoxy-1,T-binaphthyl-4,4 -bis(5-isophthalic acid)] is an organic linker between the zinc clusters Yields of the a-hydroxyamine ranging i from 70 to 95% with 62-89% ee were obtained using CM-stilbene epoxide and aniline. Lower yields and much lower ee values were found when different substituents were on the stilbene epoxide or the aniline. 

Wu P, He C, Wang J, Peng X, Li X, An Y, Duan C (2012) Photoactive chiral metal-organic frameworks for light-driven asymmetric a-alkylation of aldehydes. J Am Chem Soc 134 14991-14999... 

Nickerl G, Henschel A, Griinker R, Gedrich K, Kaskel S (2011) Chiral metal-organic frameworks and their application in asymmetric catalysis and stereoselective separation. Chemie Ingenieur Technik 83 90-103... 

Fig. 6 A synthetic approach toward homochiral metal-organic frameworks through linking chiral secondary building blocks by achiral ligands...

Keywords Chiral, Enantioselectivity, Heterogeneous catalysis, Metal-organic frameworks. Porous, Size selectivity... 

Fang Q, Zhu G, Xue M et al (2006) Structure, luminescence, and adsorption properties of two chiral microporous metal-organic frameworks. Inorg Chem 45 3582-3587... 

In this chapter we briefly review the recent progresses in the design and synthesis of metal-organic frameworks as a new class of materials with potential for NLO application. The noncentrosymmetric MOFs, discussed herein are synthesized by using either chiral ligands or unsymmetrical ligands to assemble with suitable metal ions under hydro(solvo)thermal conditions. Additionally, incorporation of alkali or alkaline earth ions into Cd carboxylate frameworks is also an effective way to produce noncentrosymmetric MOFs. 

Ruthenium-salen complex 263 was examined. Achiral salen complex 263 in the presence of chiral sulfoxide 264 progressed the cyclopropanation of diazoacetate in a highly enantioselective manner (Scheme 1.127) [184]. Chiral sulfoxide served as an axial ligand that showed good asymmetric induction. C2-symmetric chiral ruthenium-salen complex 265 contained in metal-organic frameworks worked as a chiral catalyst for cyclopropanation (Scheme 1.128) [185]. 

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