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The coordination behavior of 2-oxo-1,2-dihydroquinoline-3-carbaldehyde hydrazone ligands in ruthenium(II) and the catalytic activity of newly synthesized complexes have been studied. The complexes [RuCl(CO)(PPh3)2(L1)] (1), [RuCl(CO)(AsPh3)2(L1)] (2), [RuCl(CO)(PPh3)2(L2)] (3) and [RuCl(CO)(AsPh3)2(L2)] (4) were synthesized by reactions of [RuHCl(CO)(EPh3)3] (E = P or As) precursors with hydrazone ligands and characterized by analytical and spectroscopic methods. The molecular structure of complex 2 was identified by means of single-crystal X-ray diffraction analysis. The structural analysis revealed that all the complexes possess a distorted octahedral geometry with the ligand coordinating in a uni-negative bidentate NO fashion. Further, the catalytic efficiency of the complexes have been investigated in the case of direct amidation of alcohols with amines. The influence of base, reaction temperature and catalyst loading in the amidation reaction was also evaluated. Notably, complex 3 was found to be very efficient catalyst towards amidation of alcohols with amine. A variety of aromatic (hetero) amines and alcohols with various functional groups have also been successfully used for amidations.

Fused thiazoles are synthesized through title reaction of thiazolidine-2-thiones either with boronic acids or with boronic acid pinacol esters.

A series of Ru(II) carbonyl complexes bearing phosphine-functionalized hydrazone/thiosemicarbazone as well as triphenylarsine ligands are synthesized and applied as catalysts in N-alkylation reactions of amines, diamines and sulfonamides with benzyl alcohols.

Reactions of the elements at 800 °C with the nominal compositions RE Ag 1 − x Zn x As 2 resulted in quaternary arsenides RE Ag 1 − x Zn y As 2 in which the combined Ag and Zn content deviates increasingly from unity in the Zn-richer phases, reflecting the transition from the fully stoichiometric ternary silver-containing arsenides RE AgAs 2 to the substoichiometric zinc-containing ones RE Zn 0.67 As 2 . Powder X-ray diffraction analysis indicated SrZnBi 2 -type (space group I 4/ mmm , Z =4; RE =La, Ce) and HfCuSi 2 -type structures (space group P 4/ nmm , Z =2; RE =Pr, Nd, Sm, Gd, Tb, Dy). Single-crystal X-ray diffraction analysis performed on LaAg 0.5 Zn 0.5 As 2 , PrAg 0.5 Zn 0.5 As 2 , and NdAg 0.5 Zn 0.5 As 2 indicated that the Ag and Zn atoms are disordered within metal-centred tetrahedra and provided no evidence for distortion of the square As nets. The small electron excess tolerated in these quaternary arsenides and the absence of distortion in the square nets can be traced to the occurrence of As–As states that are only weakly antibonding near the Fermi level. PrAg 0.5 Zn 0.5 As 2 and NdAg 0.5 Zn 0.5 As 2 are paramagnetic with effective magnetic moments consistent with trivalent RE species.

A highly diastereoselective Rh-catalyzed boronic acid addition to enantiopure sulfinylimines providing γ-aryl GABA derivatives has been described. The reaction proceeds in protic solvents at room temperature and the starting material is readily prepared. The novel protocol enables the introduction of a variety of aryl substituents onto an unactivated sulfinylimine under mild conditions.

The reaction is based on the anti-stereoselective enolboration-aldolisation of 3,3,3-trifluoropropanoic acid with aryl or alkylaldehydes.

A Pd-catalyzed hydrogenation of potassium (3,3,3-trifluoroprop-1-yn-1-yl)trifluoroborate providing either the (Z)- or (E)-isomer of the vinylborate in >98% purity is described. The initially formed (Z)-isomer of the alkene is transformed to the (E)-isomer with time, irrespective of the catalyst used; coupling with bromo- and iodoarenes provides a variety of (Z)- or (E)-β-trifluoromethylstyrenes. Also, a safe synthesis of the alkynyltrifluoroborate from HFC-245fa and BF3·OEt2 has been described.

The applied catalyst can be removed by easy filtration and dried under vacuum after washing with ethyl acetate before reuse.

An auto-catalytic domino reaction, presumably involving an aza-Michael reaction, proton transfer, and lactonization, furnishing α-(aminomethyl)-γ-butyrolactones in near quantitative yields and excellent diastereoselectivity is described.

The title compounds are prepared from the elements (800 °C, 10 d) and characterized by powder and single crystal XRD, electrical resistivity measurements, and TB-LMTO-ASA band structure calculations.

The allylboration of mono-, di- and trifluorobenzaldehydes (II) with (E)-methyl 3-phenyl-2-(pinacolylmethyl)acrylate (I) yields cis-γ-fluorophenyl-α-methylene-β-phenyl-lactones (III).

Contrary to the non-fluorinated analogs, the hydroboration of trifluoromethylallene with diisopinocampheylborane provides the corresponding Z-trifluorocrotylborane reagent. Trifluorocrotylboration of a series of aldehydes with this reagent provides the corresponding syn-β-trifluoromethyl homoallyl alcohols in high diastereo- and enantioselectivities.

A convergent synthesis of indolylpyrrole derivatives has been developed from domino coupling of α-azido ketones, aromatic aldehydes, and 3-cyanocetylindoles in the presence of piperidine in aqueous medium at 80 °C via cascade Knoevenagel condensation–Michael addition–annulation in excellent yields. Further, the synthesized ortho-azidoindolylpyrroles undergo [3+2] cycloaddition with phenyl acetylene to give indolyltriazolylpyrrole hybrids in good yields. This domino transformation, efficiently generates C–C and C–N bonds in a minimum of synthetic steps resulting in three important bioactive heterocyclic frameworks, indole–pyrrole–triazole hybrids.

The use of cyclododecanone-protected thiosemicarbazide (I) for the synthesis of highly functionalized 3-amino-2-thiohydantoins (IV) is demonstrated.

The new uranyl arsenates (III), (V), (VI), (VIII), and (X) are characterized by single crystal XRD and photoluminescence spectroscopy.

A systematic examination of enolboration–aldolization of propanoic acid has led to an efficient synthesis of anti -β-hydroxy-α-methyl carboxylic acids in consistently high yields and diastereoselectivities by using B -bromodicyclohexylborane as the enolization reagent and triethylamine as the base.

Three series of quaternary pnictides, LnCuZnAs2 (Ln: Y, La—Nd, Sm, Gd—Lu), LnAgZnP2 (Ln: La—Nd, Sm, Gd—Dy), and LnAgZnAs2 (Ln: La—Nd, Sm, Gd—Dy) are prepared by solid reaction of the elements (evacuated silica tubes, 1.

A variety of aminolactones such as (III) are synthesized which exhibit excellent activities against three pancreatic cancer cell lines

The first computational study of the rearrangement reactions of oxiranes initiated by dialkylamides is presented.

A highly efficient protocol has been developed for the synthesis of aminals from γ-butyrolactam and benzaldehyde using iodine as Lewis acid catalyst. The attack of γ-butyrolactam nucleophile to intermediate N -acyliminium ion was more favorable, when aryl aldehyde bears the electron donating group (EDG). Iodine plays a key role in these reaction transformations. This current mild protocol is environmentally benign and cost-effective method for the synthesis of industrially and pharmaceutically useful scaffolds.

The boron-mediated aldol reaction of methyl phenylacetate with aliphatic and aromatic aldehydes is optimized to give syn- or anti-aldol products.

An operationally simple six-step procedure is presented for the conversion of nitriles into pyrrolidines via reduction, allylation, hydroboration, oxidation, chlorination, and cyclization.

The first stereocontrolled synthesis of the title δ-aminoboronic esters—proceeding from commercially available nitriles—via a reduction, Brown’s ‘allyl’ boration reaction, a Boc-protection, a hydroboration, an oxidative elimination of α-pinene, and an esterification reaction, has been reported in excellent enantio- and diastereoselectivities.

The presented approach is the first boron-mediated asymmetric aldol reaction of phenyl acetates.

The pnictides Ln2Mn3Cu9P7 (Ln: La—Nd, Sm, Gd—Dy) and Ln2Mn3Cu9As7 (Ln: La—Nd) are prepared from stoichiometric mixtures of the elements (800 °C, 14 d).

Treatment of difluoroallene (I) with HB(Ipc)2 provides the allylborane (II) whose reaction with various aldehydes allows highly enantioselective access to 2,2-difluorinated homoallylic alcohols.

In an effort to provide a green synthetic route for heterocyclic scaffolds, new macro analogs of acyclic Mannich derivatives have been synthesized in good yields in a one-pot, efficient fashion. The acyclic symmetrical and unsymmetrical 2-[(E)-(benzylideneamino)(aryl)methyl]cyclododecanones have been synthesized by condensation of cyclododecanone, aromatic aldehyde, and ammonium acetate in ethanolic media. By infrared, NMR, and mass spectral analyses, their structures were determined. Examination of crystal structure of a p-Cl and o-Br analogs reveals the minimum energy [3333] square conformation of cyclododecanone ring. In the crystal, molecules aggregate in dimeric subunits formed by C-Cl … π and C-H..π interactions. The reported one-pot, multichain reaction of macrocycles is the first synthetic attempt of acyclic compounds in this type of Mannich reaction involving ketones containing active methylene groups. Supplemental materials are available for this article. Go to the publisher's online ed...

A novel, simple, mild, and faster synthesis of the title compounds is developed from readily available starting materials including a convenient work-up.

An environmentally friendly approach to the diastereoselective synthesis of trans-4-oxo-3-aryl-3,4-dihydro-2H-furo[3,2-c]coumarin-2-carbonitriles, trans-2-benzoyl-3-(aryl)-2H-furo[3,2-c]chromen-4(3H)-ones and trans-ethyl-4-oxo-3-(aryl)-3,4-dihydro-2H-furo[3,2-c]chromene-2-carboxylates in good yields is described. The method is based on the sequential multicomponent reactions of 4-hydroxycoumarin, aromatic aldehydes and in situ generated cyanomethylpyridinium, phenacylpyridinium/(2-ethoxy-2-oxoethyl)pyridinium ylides, in the presence of the ionic liquid [BMIm]OH, which functions both as a catalyst and the reaction medium.

A new, convenient, and enantioselective method to prepare 2- and 2,3-substituted tetrahydrofuran derivatives is reported.

Optimized conditions are elaborated and boron reagent NBC is found to be the most efficient one to give diastereomerically pure products (III) from ester (I).

Starting from aldehydes (II), the synthesis of butenolide and dihydropyranone structures is achieved by alkenylalumination, O-protection and lactamization.

A novel chiral difluoroallylboronate (I) is applied to the reaction with various aromatic and aliphatic aldehydes affording α-gem-difluorohomoallyl alcohols.

A convenient procedure is developed for the synthesis of substituted tetrahydropyrans including unsymmetrically substituted cross-Prins products (VIII).

Imidazole/benzotriazole analogues substituted piperidin-4-one derivatives (17–26) have been synthesized. Their chemical structures were characterized by IR, 1H NMR, 13C NMR and mass spectral analysis. In addition, single crystal X-ray diffraction has also been recorded for compounds 21 and 23. The synthesized compounds were subjected to their in vitro antibacterial and antifungal activities against pathogenic microbial strains. The results pointed out that compounds 19 & 24 against B. subtilis and 20 & 24 against E. coli were explored superior inhibition activity.

Condensation of non-enolizable and enolizable aldimine-triethylborane complexes with dimethylketene acetal (II) provides access to β-amino esters (VI) and (III) from aliphatic (V) and aromatic nitriles (I) in a one-pot fashion.

Still—Gennari olefination of substrates (II) affords exclusively the (Z)-isomers (IV) which are transformed to the required pyrones (VI) (important building blocks of natural products) via (Z)-alcohols (V).

Bi2Ti2O7 microspheres are hydrothermally synthesized in high yields from an aqueous solution of Bi(NO3)3, Ti(OiPr)4, and KOH (autoclave, 180 °C, 24 h).

A series of racemic α-methylene-γ-butyrolactones is synthesized and screened against three human pancreatic cancer cell lines.