Isoselective Lactide Ring Opening Polymerisation using [2]Rotaxane Catalysts

Lim, Jason Y. C.; Yuntawattana, Nattawut; Beer, Paul D.; Williams, Charlotte K.

doi:10.1002/ange.201901592

Cited by 23 publications

(4 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Scheme 50 compares two different synthetic procedures which can be applied for the synthesis of 3,5-bis(trifluoromethyl) phenyl isothiocyanate 119. On the left side, the classical methodology based on thiophosgene is reported, [203] while on the right side Schoenebeck protocol is presented. [202] As it can be seen from Scheme 50, the latter avoiding the employment of toxic reagents and product purification allows to reduce the E factor to 83.…”

Section: Chiral Thioureas and Squaramidesmentioning

confidence: 99%

Green Chemistry Meets Asymmetric Organocatalysis: A Critical Overview on Catalysts Synthesis

2021

View full text Add to dashboard Cite

Can green chemistry be the right reading key to let organocatalyst design take a step forward towards sustainable catalysis? What if the intriguing chemistry promoted by more engineered organocatalysts was carried on by using renewable and naturally occurring molecular scaffolds, or at least synthetic catalysts more respectful towards the principles of green chemistry? Within the frame of these questions, this Review will tackle the most commonly occurring organic chiral catalysts from the perspective of their synthesis rather than their employment in chemical methodologies or processes. A classification of the catalyst scaffolds based on their E factor will be provided, and the global E factor (E G factor) will be proposed as a new green chemistry metric to consider, also, the synthetic route to the catalyst within a given organocatalytic process.

show abstract

Section: Chiral Thioureas and Squaramidesmentioning

confidence: 99%

Green Chemistry Meets Asymmetric Organocatalysis: A Critical Overview on Catalysts Synthesis

2021

View full text Add to dashboard Cite

show abstract

“…This behavior has enabled many applications including switchable catalysis. In 2019, Williams and coworkers described the control of ROP process by exploiting rotaxane conformational dynamism . Most interestingly, the achiral rotaxane species can realize high isoselectivity without adding any chiral additives.…”

Section: Recent Advancesmentioning

confidence: 99%

Controlling the Ring‐Opening Polymerization Process Using External Stimuli

Chen

2020

Chin. J. Chem.

View full text Add to dashboard Cite

Through the incorporation of stimuli‐responsive units, the properties of ring‐opening polymerization catalysts can be efficiently modulated using external stimuli. This article summarizes some of the recently reported strategies that control the ring‐opening polymerization of cyclic type monomers, using allosteric, redox, Lewis acid/base, supramolecular, electrochemical and light stimuli. These strategies enable the fine tuning of the polymerization process and the microstructure/composition of the final polymeric products.

show abstract

“…Recent years have witnessed the exploitation of mechanically interlocked molecules (MIMs) in a diverse range of applications including molecular recognition, [1–6] sensing [7–10] and catalysis, [11–14] wherein the unique microenvironment or topology of the mechanical bond underpins the functional behaviour of the system [15–18] . The exquisite topological control afforded by the mechanical bond in MIMs frequently affords enhanced host‐guest binding behaviour, with increased selectivity and binding affinities over their non‐interlocked analogues [19] …”

Section: Introductionmentioning

confidence: 99%

Dynamic Metalloporphyrin‐Based [2]Rotaxane Molecular Shuttles Stimulated by Neutral Lewis Base and Anion Coordination

Wilmore

Tse

Docker

et al. 2023

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

A series of dynamic metalloporphyrin [2]rotaxane molecular shuttles comprising of bis-functionalised Zn(II) porphyrin axle and pyridyl functionalised macrocycle components are prepared in high yield via active metal template synthetic methodology. Extensive variable temperature 1 H NMR and quantitative UV-Vis spectroscopic titration studies demonstrate dynamic macrocycle translocation is governed by an inter-component co-ordination interaction between the macrocycle pyridyl and axle Zn(II) metalloporphyrin, which serves to bias a 'resting state' co-conformation.The dynamic shuttling behaviour of the interlocked structures is dramatically inhibited by the addition of a neutral Lewis base such as pyridine, but can also be tuned via postsynthetic rotaxane demetallation of the porphyrin axle core to give free-base, or upon subsequent metallation, Ni(II) [2]rotaxane analogues. Importantly, the Lewis acidic Zn(II) porphyrin axle component is also capable of coordinating anions which induces mechanical bond shuttling behaviour resulting in a novel optical sensing response.

show abstract

Isoselective Lactide Ring Opening Polymerisation using [2]Rotaxane Catalysts

Cited by 23 publications

References 58 publications

Green Chemistry Meets Asymmetric Organocatalysis: A Critical Overview on Catalysts Synthesis

Green Chemistry Meets Asymmetric Organocatalysis: A Critical Overview on Catalysts Synthesis

Controlling the Ring‐Opening Polymerization Process Using External Stimuli

Dynamic Metalloporphyrin‐Based [2]Rotaxane Molecular Shuttles Stimulated by Neutral Lewis Base and Anion Coordination

Contact Info

Product

Resources

About