02542nas a2200241   4500008004100000022001400041245008900055210006900144260000900213300001600222490000800238520175100246100002501997700001502022700001702037700001702054700001902071700001902090700003202109700001802141700002002159856012102179       2023                        eng d  a0002-786300aCovalent organic framework cladding on peptide-amphiphile-based biomimetic catalysts0 aCovalent organic framework cladding on peptideamphiphilebased bi  cJUN   a12793-128010 v1453 a<p>
	Peptide-based biomimetic catalysts are promising materialsforefficient catalytic activity in various biochemical transformations.However, their lack of operational stability and fragile nature innon-aqueous media limit their practical applications. In this study,we have developed a cladding technique to stabilize biomimetic catalystswithin porous covalent organic framework (COF) scaffolds. This methodologyallows for the homogeneous distribution of peptide nanotubes insidethe COF (TpAzo and TpDPP) backbone, creating strong noncovalent interactionsthat prevent leaching. We synthesized two different peptide-amphiphiles,C10FFVK and C10FFVR, with lysine (K) and arginine(R) at the C-termini, respectively, which formed nanotubular morphologies.The C10FFVK peptide-amphiphile nanotubes exhibit enzyme-likebehavior and efficiently catalyze C-C bond cleavage in a buffermedium (pH 7.5). We produced nanotubular structures of TpAzo-C10FFVK and TpDPP-C10FFVK through COF claddingby using interfacial crystallization (IC). The peptide nanotubes encasedin the COF catalyze C-C bond cleavage in a buffer medium aswell as in different organic solvents (such as acetonitrile, acetone,and dichloromethane). The TpAzo-C10FFVK catalyst,being heterogeneous, is easily recoverable, enabling the reactionto be performed for multiple cycles. Additionally, the synthesis ofTpAzo-C10FFVK thin films facilitates catalysis inflow. As control, we synthesized another peptide-amphiphile, C10FFVR, which also forms tubular assemblies. By depositingTpAzo COF crystallites on C10FFVR nanotubes through IC,we produced TpAzo-C10FFVR nanotubular structuresthat expectedly did not show catalysis, suggesting the critical roleof the lysines in the TpAzo-C10FFVK.</p>
1 aMahato, Ashok, Kumar1 aPal, Sumit1 aDey, Kaushik1 aReja, Antara1 aPaul, Satyadip1 aShelke, Ankita1 aAjithkumar, Thalasseril, G.1 aDas, Dibyendu1 aBanerjee, Rahul  uhttps://library.ncl.res.in/content/covalent-organic-framework-cladding-peptide-amphiphile-based-biomimetic-catalysts02724nas a2200325   4500008004100000022001400041245014100055210006900196260000800265490000700273520157300280653002101853653004001874653004101914653002801955100001601983700002601999700002102025700002802046700002002074700002002094700001902114700001902133700002002152700002402172700003202196700002202228700002002250856012802270       2026                        eng d  a0935-964800aChirality transfer from covalent organic framework nanotubes to covalent organic framework films via chirality induction crystallization0 aChirality transfer from covalent organic framework nanotubes to   cAPR0 v383 a<p>
	We report the synthesis of homochiral crystalline covalent organic framework (COF) films that combine rigidity and porosity, offering significant promise for heterogeneous asymmetric catalysis. We prepared enantiopure COF films from achiral diamine and trialdehyde precursors using a chiral induction crystallization strategy. A Schiff-base reaction, catalyzed by a chiral acid, namely (R)- and (S)-camphorsulfonic acids (CSA) generated a beta-ketoenamine backbone with induced chirality. (R)- and (S)-camphorsulfonic acids direct the diamine-trialdehyde condensation and induce chirality during the nucleation of COF nanotubes, enabling their periodic arrangement and the formation of homochiral thin films. We successfully synthesized six distinct COF films with three different backbone functionalities: R-, S-TpAzo; R-, S-TpDPP; and R-, S-TpBDMe2, using the two enantiomers of the chiral camphorsulfonic acids. All films displayed strong circular dichroism signals and pronounced Cotton effects, confirming their enhanced enantiopurity. Both R- and S-TpAzo films exhibited the highest crystallinity, long-range order, and permanent porosity, making them particularly well-suited for catalytic applications. To demonstrate their utility, we encapsulated a bioinspired catalyst, (Et4N)2[FeIII(Cl)bTAML], within the chiral channels of the R- and S-TpAzo films. The resulting composite created a robust heterogeneous catalytic platform for the asymmetric epoxidation of alkenes, achieving excellent activity and enantioselectivity under ambient conditions.</p>
10achiral induction10acovalent organic framework nanotube10acovalent organic framework thin film10aheterogeneous catalysis1 aBag, Saikat1 aChatterjee, Debasmita1 aMahapatra, Rohan1 aSasmal, Himadri, Sekhar1 aKhatua, Arindam1 aGiri, Madhurima1 aPaul, Satyadip1 aShelke, Ankita1 aAlmasoud, Najla1 aAlomar, Taghrid, S.1 aAjithkumar, Thalasseril, G.1 aGupta, Sayam, Sen1 aBanerjee, Rahul  uhttps://library.ncl.res.in/content/chirality-transfer-covalent-organic-framework-nanotubes-covalent-organic-framework-films