Accessing Bioactive Hydrazones by the Hydrohydrazination of Terminal Alkynes Catalyzed by Gold(I) Acyclic Aminooxy Carbene Complexes and Their Gold(I) Arylthiolato and Gold(III) Tribromo Derivatives: A Combined Experimental and Computational Study.

Hydrohydrazination of terminal alkynes with hydrazides yielding hydrazones - were successfully catalyzed by a series of gold(I) acyclic aminooxy carbene complexes of the type [{(4-R-2,6--Bu-CHO)(N(R))}methylidene]AuCl, where R = H, R = Me (); R = H, R = Cy (); R = -Bu, R = Me (); R = -Bu, R = Cy (). The mass spectrometric evidence corroborated the existence of the catalytically active solvent-coordinated [(AAOC)Au(CHCN)]SbF (-) species and the acetylene-bound [(AAOC)Au(HC≡CPhMe)]SbF () species of the proposed catalysis cycle. The hydrohydrazination reaction was successfully employed in synthesizing several bioactive hydrazone compounds (-) with anticonvulsant properties using a representative precatalyst ().

Discrete Singular Metallophilic Interaction in Stable Large 12-Membered Binuclear Silver and Gold Metallamacrocycles of Amido-Functionalized Imidazole and 1,2,4-Triazole-Derived N-Heterocyclic Carbenes.

Metallophilic interactions were observed in four pairs of 12-membered metallamacrocyclic silver and gold complexes of imidazole-derived N-heterocyclic carbenes (NHCs), [1-(R)-3-N-(2,6-di-(R)-phenylacetamido)-imidazol-2-ylidene]M [R = -MeCH, R = Me, M = Ag () and Au (); R = Me, R = -Pr, M = Ag () and Au (); R = Et, R = -Pr, M = Ag () and Au ()], and a 1,2,4-triazole-derived N-heterocyclic carbene (NHC), [1-(-Pr)-4-N-(2,6-di-(-Pr)-phenylacetamido)-1,2,4-triazol-2-ylidene]M [M = Ag () and Au ()]. The X-ray diffraction, photoluminescence, and computational studies indicate the presence of metallophilic interactions in these complexes, which are significantly influenced by the sterics and the electronics of the N-amido substituents of the NHC ligands. The argentophilic interaction in the silver - complexes was stronger than the aurophilic interaction in the gold - complexes, with the metallophilic interaction decreasing in the order > > > > > > > .

One pot tandem dual CC and CO bond reductions in the β-alkylation of secondary alcohols with primary alcohols by ruthenium complexes of amido and picolyl functionalized N-heterocyclic carbenes.

Two different classes of ruthenium complexes, namely, [1-mesityl-3-(2,6-Me-phenylacetamido)-imidazol-2-ylidene]Ru(-cymene)Cl (1c) and {[1-(pyridin-2-ylmethyl)-3-(2,6-Me-phenyl)-imidazol-2-ylidene]Ru(-cymene)Cl}Cl (2c), successfully catalyzed the one-pot tandem alcohol-alcohol coupling reactions of a variety of secondary and primary alcohols, in moderate to good yields of . 63-89%. The mechanistic investigation performed on two representative catalytic substrates, 1-phenylethanol and benzyl alcohol using the neutral ruthenium (1c) complex showed that the catalysis proceeded a partially reduced CC hydrogenated carbonyl species, [PhCOCHCHPh] (3'), to the fully reduced CO and CC hydrogenated secondary alcohol, [PhCH(OH)CHCHPh] (3).

Potent Anticancer Activity with High Selectivity of a Chiral Palladium N-Heterocyclic Carbene Complex.

Five enantiomeric pairs of palladium complexes of 1,2,4-triazole-derived chiral N-heterocyclic carbene ligands were investigated to probe the influence of chirality on the compound's anticancer activity. Although no chirality-related influence was observed for any of the enantiomeric pair, strong anticancer activity was seen for a particular pair, (1,2)- and (1,2,5)-, which was significantly more active than the benchmark drug cisplatin for human breast cancer cells, MCF-7 (ca. 24-27-fold), and human cervical cancer cells, HeLa (ca.

Distinct Mechanoresponsive Luminescence, Thermochromism, Vapochromism, and Chlorine Gas Sensing by a Solid-State Organic Emitter.

In this study, we report a synthetically simple donor-acceptor (D-A)-type organic solid-state emitter that displays unique fluorescence switching under mechanical stimuli. Orange and yellow emissive crystals of (, ) exhibit an unusual "back and forth" fluorescence response to mechanical force. Gentle crushing (mild pressure) of the orange or yellow emissive crystal results in hypsochromic shift to cyan emissive fragments (λ = 498-501 nm) with a large wavelength shift Δλ = -71 to -96 nm, while further grinding results in bathochromic swing to green emissive powder λ = 540-550 nm, Δλ = +40 to 58 nm.