Metal–organic frameworks with designed chiral recognition sites

Abstract

Linking struts containing Cram-like bisbinaphthyl[22]crown-6 with Zn(4)O(CO(2))(6) joints affords metal-organic frameworks with chiral recognition sites that are highly designed, ordered and placed in a precise manner throughout the entire crystal.

Chiral Metal‐Organic Frameworks and Their Application in Asymmetric Catalysis and Stereoselective Separation

“…Adsorption behavior and ee values for the smaller or bulkier guests were significantly inferior. In most cases the (R)-configured frameworks (33) and (34) as well as (S)-32 have a preference for the (S)-enantiomer (with the exception of (S)-PhSO-Me for (33) and (S)-PhSO-i-Pr for (34)). In addition to adsorption experiments of the three frameworks, computational calculations and catalytic studies were carried out [63].…”

“…In the small pores of (32) only small alkyl aryl sulfoxides were adsorbed with ee values up to 60 % for PhSOMe. The wider channels of material (33) lead to moderate to good adsorption values with low to moderate enantioselectivities for PhSO-Me (19 % ee), PhSO-i-Pr (15 % ee) and 2-NaphSO-Me (31 % ee) in dichloromethane. Change of solvent to acetonitrile caused the highest measured ee value of 62 % for PhSO-Me, while lowering the one observed for bulkier naphthalene sulfoxide.…”

“…Heating zinc nitrate, the rigid bridging linker 2,6-naphthalene dicarboxylic acid (H 2 ndc) or 4,4′-biphenyldicarboxylic acid (H 2 bpdc) and the chiral (R)-mandelic acid (H 2 man) leads to colorless single-crystals [63]. Zn 2 (ndc)[(R)-man](DMF) (33) and Zn 2 (bpdc)[(R)-man](DMF) (34) have structures similar to (32), but, with larger pores and opposite absolute configuration of the chiral centers. The pore sizes estimated from single crystal analysis are approx.…”

Cavity-Assembled Porous Solids (CAPSs) for Nanospace-Specific Functions

“…44 They also applied similar strategy to the construction of MOF with asymmetric recognition sites with the aid of binaphthyl skeleton. 42,45 Pillararene Pillararene was first reported by Ogoshi et al in 2008 as a new type of macrocyclic host. 46 Pillar [5]arene can be prepared from the reaction between 1,4-dimethoxybenzene and paraformaldehyde in the presence of BF 3 ¢Et 2 O as a catalyst.…”

Bis-(thiosemicarbazonato) Zn(ii) complexes as building blocks for construction of supramolecular catalysts

“…The interest in these materials is fuelled by ( potential) application in separation techniques, gas (hydrogen) storage, recognition, sensing, and catalysis. [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] Metalloporphyrins 24 provide versatile building blocks for the construction of all types of supramolecular assemblies and they are also frequently used for the construction of porous solid materials. In our group metalloporphyrins have been used as building blocks to encapsulate transition metal catalysts.…”