5--Arylaminothiazoles with pyridyl groups and their first-row transition metal complexes: synthesis, photophysical properties, and Zn sensing.

A series of 5--arylaminothiazoles were synthesized with facile diversity-oriented synthesis from readily available starting materials the reaction of thioamide dianions and thioformamides. The introduction of various substituents at the 2-position of a thiazole ring (, 2-pyridyl, 4-methylpyridyl, and phenyl groups) and on the nitrogen atom (, -tolyl and phenyl groups) significantly influenced the absorption and emission spectra of the isolated compounds. X-ray analysis confirmed that the substituents at the amino site were twisted from a thiazole ring, while the formation of its nickel complex showed dinuclear metal complexes bridged with chlorine atoms.

Stereoselective Transesterification of P-Chirogenic Hydroxybinaphthyl Phosphinates.

The substitution reaction of phosphinates with a binaphthyloxy group at the phosphorus atom with lithium alkoxides proceeded with good to high efficiencies to give P-chirogenic phosphinates with a high enantiomeric ratio. As alcohols, primary, secondary, and tertiary alcohols could be used, and the use of tert-butyl alcohol yielded the products with a higher enantiomeric ratio. A substrate with two different alkyl groups on the phosphorus atom could also participate in the substitution reaction to give the corresponding products in good yields with excellent selectivity.

Boron complexes of thiazole-bridged 1,5-bidentate nitrogen ligands: synthesis and acid-responsive photophysical properties.

Boron complexes of 1,5-bidentate nitrogen ligands with a thiazole linker were synthesized by the halogenation of 5-H thiazoles followed by Buchwald-Hartwig amination and complexation with BF·EtO. These boron complexes showed a large Stokes shift of up to 125 nm, which is in marked contrast to that observed for ordinary BODIPYs. The absorption and emission spectra of the boron complexes were almost independent of the substituents in the complexes as well as the solvents used for the measurement.

Hormetic Effects of Binaphthyl Phosphonothioates as Pro-oxidants and Antioxidants.

Organophosphorous compounds with such a wide variety in structure, application, and biochemical activities include pesticides, herbicides, nerve agents, medicines, reagents in organic chemistry, and additives for polymers. Binaphthyl phosphono-, phosphorothioates, and their derivatives, are useful chiral catalysts for various asymmetric reactions and are expected to act as heavy metal scavengers. In this study, we aimed to evaluate the neurotoxicity and biochemical properties of a new series of binaphthyl phosphonothioates called KK compounds using the mouse hippocampal HT22 cells.

Chemoselective and Stereoselective Alcoholysis of Binaphthyl Phosphonothioates: Straightforward Access to Both Stereoisomers of Biologically Relevant -Stereogenic Phosphonothioates.

-Stereogenic phosphonothioates have attracted great attention due to their potent biological activities as analogues of phosphoric acids and phosphorothioates. We demonstrate here straightforward access to stereogenic phosphonothioates through the use of binaphthyl phosphonothioates as a chiral template. The first-step alcoholysis of binaphthyl phosphonothioates proceeded via a transfer of the axial chirality of a binaphthyl group to the central chirality of a phosphorus atom to give only monoalcohol adducts with moderate to excellent diastereoselectivities.

A Modular Approach to Phosphorescent π-Extended Heteroacenes.

A modular route to previously inaccessible classes of ring-fused π-extended heteroacenes bearing the heavy inorganic element tellurium (Te) is presented. These new materials can be viewed as n-doped analogs of molecular graphene subunits that exhibit color tunable visible light phosphorescence in the solid state and in the presence of air. The general mechanism of phosphorescence in these systems was probed experimentally and computationally via time-dependent density functional theory (TD-DFT).

Synthesis of Chiral Selenazolines from N-Acyloxazolidinones via a Selenative Rearrangement of Chiral Cyclic Skeletons.

A synthetic route to chiral selenazolines from readily available N-acyloxazolidinones via a selenative rearrangement of a chiral cyclic skeleton is reported. The reaction proceeds in the presence of elemental selenium, a hydrochlorosilane, and an amine. Although the stability of the obtained selenazoline products is relatively low, a wide range of selenazolines was successfully prepared.

The Construction and Application of C=S Bonds.

The current section presents an overview of the fundamental aspects of thiocarbonyl compounds, such as thioaldehydes and thioketones. Firstly, a theoretical approach and a physical-organic experimental approach disclose their properties. Secondly, their synthetic reactions are introduced.

Selenolactams as Synthetic Intermediates for the Synthesis of Polycyclic Amines via Seleno-Claisen Rearrangements.

A highly diastereoselective α-allylation of selenolactams with allyl halides is reported. DFT analyses and experimental observations suggested that this reaction proceeds via a Se-allylation of the eneselenolates of the lactams followed by a seleno-Claisen rearrangement. The thus-obtained products could be efficiently transformed into polycyclic amines using a previously developed sequential addition of organometallic reagents and ring-closing metathesis.

Hydrolysis of Phosphonothioates with a Binaphthyl Group: P-Stereogenic O-Binaphthyl Phosphonothioic Acids and Their Use as Optically Active Ligands and Chiral Discriminating Agents.

The hydrolysis of phosphonothioates with a binaphthyl group afforded the first example of O-(2'-hydroxy)binaphthyl phosphonothioic acids in good to high yields and >95:5 diastereoselectivity. The reaction proceeds via an axis-to-center chirality-transfer reaction. The ability of these acids to act as chiral molecular auxiliaries was demonstrated by using them as optically active ligands for the asymmetric ethylation of benzaldehyde and as a chiral discriminating agent for chiral aliphatic amines.

Experimental and Theoretical Examination of the Radical Cations Obtained from the Chemical and Electrochemical Oxidation of 5-Aminothiazoles.

Chemical or electrochemical one-electron oxidation of 5--arylaminothiazoles was found to afford stable radical cations. For chemical oxidation, 1 equivalent of [(4-BrCH)N][SbCl] (Magic Blue, MB) was added to CHCl solutions of the thiazoles, and the thus-obtained radicals showed light absorption in the near-infrared region. Electrochemical oxidation also led to bathochromic shifts in the absorption bands, and the obtained spectra were similar to those derived from the chemically oxidized species.

Employing BINOL-Phosphoroselenoyl Chloride for Selective Inositol Phosphorylation and Synthesis of Glycosyl Inositol Phospholipid from Entamoeba histolytica.

The chemical synthesis of glycosyl inositol phospholipids from Entamoeba histolytica is reported. The key feature of this synthesis is a regioselective phosphorylation reaction that occurs through desymmetrization of a myo-inositol derivative with phosphoroselenoyl chloride. A new protecting-group strategy was developed that utilizes allyl and alloc groups to synthesize complex glycolipids bearing unsaturated lipids.

Imidazo[1,5-a]pyridin-3-ylidenes as π-accepting carbene ligands: substituent effects on properties of N-heterocyclic carbenes.

Various 1-substituted-imidazo[1,5-a]pyridin-3-ylidenes were prepared and characterized. The fundamental character and the effects of substituents on the imidazo[1,5-a]pyridine backbone on the electronic character of carbenes were evaluated using rhodium complexes and selenium adducts. C NMR chemical shifts of carbene carbons in imidazo[1,5-a]pyridin-3-ylidene and H and C NMR spectra of olefin moieties trans to the carbene in Rh(nhc)(cod)Cl complexes shifted relatively downfield compared to those for the corresponding complexes bearing conventional N-heterocyclic carbenes (NHCs).

Acid-Responsive Absorption and Emission of 5--Arylaminothiazoles: Emission of White Light from a Single Fluorescent Dye and a Lewis Acid.

10.1002/open.201600059.

Sequential Deprotonation-Alkylation of Binaphthyloxy-Substituted Phosphonochalcogenoates: Chiral Tri- and Tetrasubstituted Carbon Centers Adjacent to a Phosphorus Atom.

Sequential deprotonation and alkylation of 1,1'-binaphthyloxy-substituted phosphonoselenoates and phosphonates resulted in the diastereoselective formation of chiral tri- and tetrasubstituted carbon centers adjacent to a phosphorus atom.

Sequential Addition Reaction of Sulfanylmethyllithiums and Grignard Reagents to Thioformamides Leading to the Formation of 2-Phenyl-2-sulfanylethyl Tertiary Amines.

The reaction of sulfanylmethyllithiums generated from benzylsulfanes and n-BuLi with N,N-dimethylthioformamide followed by the addition of Grignard reagents gave 2-phenyl-2-sulfanyl tertiary amines in moderate to good yields. A range of Grignard reagents involving primary alkyl, aryl, vinyl, and alkynyl Grignard reagents were used. Two carbon-carbon bond-forming reactions were achieved through a one-pot reaction.

Direct C-H Bond Arylation of Thienyl Thioamides Catalyzed by Pd-Phenanthroline Complexes.

A direct C-H bond arylation method for thienyl thioamides catalyzed by [Pd(phen)2](PF6)2 was developed. This reaction selectively afforded 2-monoarylated products, while the corresponding amide thiophene derivatives furnished 2,5-diarylated products. Mechanistic studies revealed that a Pd(II)-bisthioamide complex should be the active species for the reaction of thienyl thioamides in the presence of catalytic amounts of [Pd(phen)2](PF6)2.

5-N-Arylaminothiazoles as Highly Twisted Fluorescent Monocyclic Heterocycles: Synthesis and Characterization.

A series of 5-N-arylaminothiazoles was prepared by reacting thioamide dianions derived from secondary thioamides with thioformamides, followed by sequential oxidation with iodine. X-ray analyses demonstrated that they adopt structures that are highly twisted from planar conformations. Their orientations were tuned by the steric and/or electronic interactions of the substituents at their 2-, 4-, and 5-positions.

α-Hydroxy and α-Oxo Selenoamides: Synthesis via Nucleophilic Selenocarbamoylation of Carbonyl Compounds and Characterization.

Carbonyl compounds were added to selenocarbamoyllithiums to generate α-hydroxy and α-oxo selenoamides. Their conformations were determined by X-ray analyses. These compounds adopted conformations that were almost identical to those of ordinary amides.

Fluorinative hydrolysis of phosphorothioic acid esters with a binaphthyl group through axis-to-center chirality transfer leading to the formation of P-chiral phosphorothioic monofluoridic acid salts.

Asymmetric synthesis of P-chiral phosphorothioic monofluoridic acid ammonium salts was achieved via axis-to-center chirality transfer reactions by using phosphorothioic acid O-esters with a binaphthyl group, and the absolute stereochemistry of the salts was determined by X-ray analyses and by comparison of their CD spectra.

Facile synthetic method for diverse polyfunctionalized imidazoles by means of Pd-catalyzed C-H bond arylation of N-methyl-4,5-dibromoimidazole.

C-H bond-selective arylation reaction of 4,5-dibromoimidazole with aryl iodides, catalyzed by the palladium-1,10-phenanthroline complex [Pd(phen)2](PF6)2, has been developed. The process tolerates the presence of a variety of functional groups on the aryl halide substrates. The products formed in these reactions were transformed to a variety of polyfunctionalized imidazoles by taking advantage of selective reactions of remaining C-Br bonds.

Reaction of selenoamide dianions with thio- and selenoformamides leading to the formation of 5-aminoselenazoles: photophysical and electrochemical properties.

5-Amino-2-selenazolines were synthesized by reacting selenoamide dianions generated from secondary selenoamides and BuLi with tertiary thio- and selenoformamides followed by treatment with iodine. The resulting 5-amino-2-selenazolines were further oxidized with iodine to give 5-aminoselenazoles in moderate to good yields. The general tendencies in the (77)Se NMR spectra of the starting selenoamides, 5-amino-2-selenazolines, and 5-aminoselenazoles were determined.

Anti-Markovnikov hydrophosphoroselenoylation of alkenes using phosphorodiselenoic acid esters leading to the formation of phosphonoselenoic acid esters.

Phosphorodiselenoic acid esters with a binaphthyl group were reacted with alkenes in the presence of Bu3SnH and AIBN to give phosphonoselenoic acid esters in moderate to good yields. The addition of a phosphoroselenoyl group to alkenes proceeded in an anti-Markovnikov fashion. The diastereoselectivity was improved by the introduction of substituents to 3,3'-positions of a binaphthyl group.