ABSTRACT
A molecular three-input AND logic gate with a naphthalimide fluorophore communicates the presence of a congregation of three biologically relevant cations in aqueous methanol with a 25-fold fluorescence enhancement and ΦFmax of 0.203.
ABSTRACT
A novel fluorescent molecular logic gate with a 'fluorophore-spacer1-receptor1-spacer2-receptor2' format is demonstrated in 1 : 1 (v/v) methanol/water. The molecule consists of an anthracene fluorophore, and tertiary alkyl amine and N-(2-methoxyphenyl)aza-15-crown-5 ether receptors. In the presence of threshold concentrations of H+ and Na+, the molecule switches 'on' as an AND logic gate with a fluorescence quantum yield of 0.21 with proton and sodium binding constants of log ßH+ = 9.0 and log ßNa+ = 3.2, respectively. At higher proton levels, protonation also occurs at the anilinic nitrogen atom ether with a log ßH+ = 4.2, which allows for Na+, H+-enabled OR (OR + AND circuit) and H+-driven ternary logic functions. The reported molecule is compared and contrasted to classic anthracene-based Na+ and H+ logic gates. We propose that such logic-based molecules could be useful tools for probing the vicinity of Na+, H+ antiporters in biological systems.
Subject(s)
Amines/chemistry , Anthracenes/chemistry , Crown Ethers/chemistry , Fluorescent Dyes/chemistry , Hydrogen/chemistry , Sodium/chemistry , Fluorescent Dyes/chemical synthesis , Methanol/chemistry , Molecular Structure , Water/chemistryABSTRACT
The flow synthesis of ortho-substituted carboxylic acids, using carbon monoxide gas, has been studied for a number of substrates. The optimised conditions make use of a simple catalyst system compromising of triphenylphosphine as the ligand and palladium acetate as the pre-catalyst. Carbon monoxide was introduced via a reverse "tube-in-tube" flow reactor at elevated pressures to give yields of carboxylated products that are much higher than those obtained under normal batch conditions.
ABSTRACT
A flow system to perform Chan-Lam coupling reactions of various amines and arylboronic acids has been realised employing molecular oxygen as an oxidant for the re-oxidation of the copper catalyst enabling a catalytic process. A tube-in-tube gas reactor has been used to simplify the delivery of the oxygen accelerating the optimisation phase and allowing easy access to elevated pressures. A small exemplification library of heteroaromatic products has been prepared and the process has been shown to be robust over extended reaction times.
ABSTRACT
The synthesis of thiazoles and thiophenes starting from nitriles, via a modified Gewald reaction has been studied for a number of different substrates. 1,4-Dithiane-2,5-diol was used as the aldehyde precursor to give either 2-substituted thiazoles or 2-substituted aminothiophenes depending on the substitution of the α-carbon to the cyano group.
ABSTRACT
A novel supramolecular three-input AND logic gate is demonstrated as a 'lab-on-a-molecule' for monitoring the Na(+), pH and pE levels in solution by communicating a fluorescence signal. The fluorescence signal is modulated by three photoinduced electron transfer reactions that are controlled by an unprecedented combination of two cation binding events and one redox reaction.
