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1.
J Clin Med ; 11(1)2022 Jan 04.
Article in English | MEDLINE | ID: mdl-35011997

ABSTRACT

Much research has been conducted on how patients may be served through new advances in perioperative anaesthetic care. However, adaptations of standardised care methodologies can only provide so many novel solutions for patients and caregivers alike. Similarly, unique methods such as nanoscopic liposomal package delivery for analgesics and affective numbing agents pose a similar issue-specifically that we are still left with the dilemma of patients for whom analgesics and numbing agents are ineffective or harmful. An examination of the potential gains that may result from the targeted development of nanorobotics for anaesthesia in perioperative care will be presented in this essay to help resolve this pending conflict for the research community. This examination should therefore serve as a "call to action" for such research and a "primer" for those for whom the method's implementation would most directly impact.

2.
J Am Chem Soc ; 143(21): 8000-8010, 2021 Jun 02.
Article in English | MEDLINE | ID: mdl-34028258

ABSTRACT

Colored charge-transfer complexes can be formed by the association between electron-rich donor and electron-deficient acceptor molecules, bringing about the narrowing of HOMO-LUMO energy gaps so that they become capable of harnessing visible light. In an effort to facilitate the use of these widespread, but nonetheless weak, interactions for visible light photocatalysis, it is important to render the interactions strong and robust. Herein, we employ a well-known donor-acceptor [2]catenane-formed by the mechanical interlocking of cyclobis(paraquat-p-phenylene) and 1,5-dinaphtho[38]crown-10-in which the charge-transfer interactions between two 4,4'-bipyridinium and two 1,5-dioxynaphthalene units are enhanced by mechanical bonding, leading to increased absorption of visible light, even at low concentrations in solution. As a result, since this [2]catenane can generate persistent bipyridinium radical cations under continuous visible-light irradiation without the need for additional photosensitizers, it can display good catalytic activity in both photo-reductions and -oxidations, as demonstrated by hydrogen production-in the presence of platinum nanoparticles-and aerobic oxidation of organic sulfides, such as l-methionine, respectively. This research, which highlights the usefulness of nanoconfinement present in mechanically interlocked molecules for the reinforcement of weak interactions, can not only expand the potential of charge-transfer interactions in solar energy conversion and synthetic photocatalysis but also open up new possibilities for the development of active artificial molecular shuttles, switches, and machines.

3.
Front Chem ; 9: 620017, 2021.
Article in English | MEDLINE | ID: mdl-33996739

ABSTRACT

This work presents the first transition metal-free synthesis of oxygen-linked aromatic polymers by integrating iterative exponential polymer growth (IEG) with nucleophilic aromatic substitution (SNAr) reactions. Our approach applies methyl sulfones as the leaving groups, which eliminate the need for a transition metal catalyst, while also providing flexibility in functionality and configuration of the building blocks used. As indicated by 1) 1H-1H NOESY NMR spectroscopy, 2) single-crystal X-ray crystallography, and 3) density functional theory (DFT) calculations, the unimolecular polymers obtained are folded by nonclassical hydrogen bonds formed between the oxygens of the electron-rich aromatic rings and the positively polarized C-H bonds of the electron-poor pyrimidine functions. Our results not only introduce a transition metal-free synthetic methodology to access precision polymers but also demonstrate how interactions between relatively small, neutral aromatic units in the polymers can be utilized as new supramolecular interaction pairs to control the folding of precision macromolecules.

4.
AI Soc ; 36(3): 911-930, 2021.
Article in English | MEDLINE | ID: mdl-33223621

ABSTRACT

This addendum expands upon the arguments made in the author's 2020 essay, "Legal Personhood for Artificial Intelligence: Citizenship as the Exception to the Rule", in an effort to display the significance human augmentation technologies will have on (feasibly) inadvertently providing legal protections to artificial intelligence systems (AIS)-a topic only briefly addressed in that work. It will also further discuss the impacts popular media have on imprinting notions of computerised behaviour and its subsequent consequences on the attribution of legal protections to AIS and on speculative technological advancement that would aid the sophistication of AIS.

5.
Angew Chem Int Ed Engl ; 58(4): 1035-1040, 2019 Jan 21.
Article in English | MEDLINE | ID: mdl-30402995

ABSTRACT

Enantioselective electrophilic aromatic nitration methodology is needed to advance chirality-assisted synthesis (CAS). Reported here is an enantioselective aromatic nitration strategy operating with chiral diester auxiliaries, and it provides an enantioselective synthesis of a C3v -symmetric tribenzotriquinacene (TBTQ). These axially-chiral structures are much sought-after building blocks for CAS, but they were not accessible prior to this work in enantioenriched form without resolution of enantiomers. This nitration strategy controls the stereochemistry of threefold nitration reactions from above the aromatic rings with chiral diester arms. Dicarbonyl-to-arenium chelation rigidifies the reaction systems, so that remote stereocenters position the ester-directing groups selectively over specific atoms of the TBTQ framework. Closely guided by computational design, a more selective through-space directing arm was first predicted with density functional theory (DFT), and then confirmed in the laboratory, to outperform the initial structural design. This enantio- and regioselective TBTQ synthesis opens a new pathway to access building blocks for CAS.

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