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Catalytic reaction of arylhydroxamic acids with alkenes represents a convenient method for preparation of biologically active dihydroisoquinolones. Here, the rhodium(III) complex [(C5H2tBu2CH2tBu)RhCl2]2, which allows one to carry out such reactions with high regioselectivity to obtain 4‐substituted dihydroisoquinolones in 72–97 % yields, is described. The regioselectivity is provided by the bulky cyclopentadienyl ligand of the catalyst, which is formed through a [2+2+1] cyclotrimerization of tert‐butylacetylene. The catalytic reaction tolerates various distant functional groups in alkenes, but is inhibited by bulky (e.g., tBu) or strongly coordinating (e.g., imidazolyl) substituents. Some of the prepared dihydroisoquinolones effectively inhibit growth of phytopathogenic fungi. Regioselective synthesis of biologically active dihydroisoquinolones was achieved by using rhodium(III) catalyst with bulky cyclopentadienyl ligand, which was formed from three tert‐butylacetylenes. [ABSTRACT FROM AUTHOR]

The demethylation reactions of the cyclohexadienyl complexes [(η-X-SMe2-7,8-C2B9H10)Fe(η5-C6H7)] {X = 9 ( 1a), 10 ( 1b); X is the number of the substituent position} with PhCH2SNa in N, N-dimethylformamide (DMF) and subsequent protonation by acetic acid lead to the iron-benzene complexes [(η-X-SMe-7,8-C2B9H10)Fe(η-C6H6)] ( 2a and 2b). The visible-light irradiation of 2a in the presence of tBuNC or [Cp*Fe(η- cyclo-P5)] (Cp* = pentamethylcyclopentadienyl) affords the neutral half-sandwich complex [(η-9-SMe-7,8-C2B9H10)Fe( tBuNC)3] ( 3) or the triple-decker complex [(η-9-SMe-7,8-C2B9H10)Fe(µ-η:η- cyclo-P5)FeCp*] ( 4). The reaction of 2b with (THF)W(CO)5 (THF = tetrahydrofuran) selectively gives the iron-tungsten dinuclear complex [(η-10-SMe{W(CO)5}-7,8-C2B9H10)Fe(η-C6H6)] ( 5). The structures of 2a, 4, and 5 were determined by X-ray diffraction. Electrochemistry revealed that the redox processes of the SMe-substituted ferracarboranes are cathodically shifted (by ca. 350 mV) with respect to the corresponding redox changes of the SMe2 analogs. The Fe-C6H6 bonding in 2a and the related benzene complexes [(η-9-SMe2-7,8-C2B9H10)Fe(η-C6H6)]+ and [(η-7,8-C2B9H11)Fe(η-C6H6)] was analyzed by energy-decomposition analysis. [ABSTRACT FROM AUTHOR]

Metallacarborane [1,8-Me2-2,2-(C 2 H 4 )2-7-SMe2-2,1,8-IrC 2 B 9 H 8 ] (1) was obtained by an interaction of [(C 2 H 4 )2IrCl] 2 with Tl[9-SMe 2 -7,8-Me2-7,8-C 2 B 9 H 8 ]. Reaction proceeds with a low temperature “1,2 → 1,7” polyhedral rearrangement. Ethene complex 1 reacts with iodine in toluene with the formation of ionic compound 3, consisting of cationic [(1,8-Me2-7-SMe2-2,1,8-IrC 2 B 9 H 8 )2I 3 ]+ (3a+) and anionic [(1,8-Me 2 -7-SMe-2,1,8-IrC 2 B 9 H 8 )2I 3 ]− (3b–) iodide species. The structures of 1 and 3 were determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

The nucleophile-induced rearrangement of cyclic Nalkoxy- N-(silyloxy)enamines was investigated. As a result, a new strategy for the synthesis of β-pyranone and β-furanone derivatives from nitro compounds is suggested. [ABSTRACT FROM AUTHOR]

Condensation of 1,3-dimethyl-3a,9a-diphenyl-3,3a,9,9a-tetrahydroimidazo[4,5-e]-1,3-thiazolo[3,2-b]-1,2,4-triazine-2,7(1H,6H)-dione with isatins afforded 6-(2-oxo-1,2-dihydro-3H-indol-3-ylidene)-3,3a,9,9a-tetrahydro-1,3-dimethyl-3a,9a-diphenylimidazo-[4,5-e]thiazolo[3,2-b]-1,2,4-triazine-2,7(1H,6H)-diones; a new conglomerate (space group P212121) was found by an X-ray diffraction study. [ABSTRACT FROM AUTHOR]

The chemical bonding between chlorate anions, its energy and role in the crystal packing formation of the title compound were examined within topological analysis of electron density function. [Copyright &y& Elsevier]

3-Imino-5,7-dimethyl-4a,7a-diphenylperhydroimidazo[4,5-e]-1,2,4-triazin-6-one and 5,7-dimethyl-4a,7a-diphenylperhydroimidazo-[4,5-e]-1,2,4-triazine-3,6-dione were synthesized for the first time via the condensation of aminoguanidine and semicarbazide (as hydrochlorides) with 1,3-dimethyl-4,5-dihydroxy-4,5-diphenylimidazolidin-2-one, and a new conglomerate (space group P21) was found by XRD study. [Copyright &y& Elsevier]

The reactions of [(η 5 -indenyl)IrI 2 ] η with CpTl or arenes in the presence of AgBF 4 afford [(η 5 -indenyl)IrCp] + or [(η 5 -indenyl)Ir(arene)] 2+ cations (arene = benzene, mesitylene, durene or hexamethylbenzene); the structures of (η 5 -indenyl)-Ir(C 2 H 4 ) 2 and [(η 5 -indenyl)IrCp]PF 6 were characterized by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Reactions of [(C2H4)2RhCl]2 or [(coe)2RhCl]2 (coe = cyclooctene) with AgPF6 and arenes, followed by addition of 3-hexyne, give the cyclobutadiene complexes [(C4Et4)Rh(arene)]+ in 40-65% yield (arene = tert-butylbenzene, p-xylene, mesitylene, 4-mesitylbutanoic acid). In the absence of arenes, the hexaethylbenzene complex [(C4Et4)Rh(C6Et6)]+ is formed in 70% yield as a result of cyclotrimerization of 3-hexyne in the coordination sphere of rhodium. Similar reaction of [(coe)2IrCl]2 with AgPF6 and 3-hexyne leads to [(C4Et4)Ir(C6Et6)]+, which is apparently the first reported cyclobutadiene iridium complex. DFT calculations suggest that formation of the model cyclobutadiene complex [(C4Me4)Rh(C6H6)]+ from bis(alkyne) intermediate [(C2Me2)2Rh(C6H6)]+ can proceed via a metallacycle transition state with a low energy barrier of 14.5 kcal mol-1. [ABSTRACT FROM AUTHOR]

Abstract: Reactions of [(C4Me4)Co(MeCN)3]PF6 with aromatic amino acid derivatives give the arene complexes [(C4Me4)Co(amino acid)]PF6 (amino acid = ethyl ester of N-acetylphenylalanine, N-acetyltyrosine or N-acetyltryptophan) in 75–85% yields; the structure of the tyrosine complex was determined by X-ray diffraction. [Copyright &y& Elsevier]

5,7-Diaryl-1,3-dimethyl-2,4-dioxo-1H,2H,3H,4H-pyrano[4,3-d]pyrimidinium bromides react with malonodinitrile to form 1,3-dimethyl- 2,4-dioxo-1H,2H,3H,4H-quinazolines, whereas their reaction with nitromethane gives dihydro-1,3-dimethyl-5-nitromethyl-2H- pyrano[4,3-d]pyrimidine-2,4(3H)-diones, the structure of one of them was established by X-ray analysis. [Copyright &y& Elsevier]

A new method of dihydrothiadiazine cycle annelation to 1,2,4-triazole derivatives is suggested and a ring opening reaction of the obtained dihydrothiadiazine cycle is found, leading to a substituted desoxybenzoine; the structures of both reaction products are supported by X-ray analysis. [Copyright &y& Elsevier]

Reactions of the cyclohexadienyl ruthenium complex [(η 5 -C 6 H 3 Me 4 )Ru(C 10 H 8 )] + ( 1 ) with 2-electron ligands L lead to replacement of the naphthalene ligand with formation of the half–sandwich complexes [(η 5 -C 6 H 3 Me 4 )RuL 3 ] + (L = MeCN, t BuNC, P(OEt) 3 , 1,3,5-triaza-7-phosphaadamantane). Similar reactions with P(OMe) 3 or dppe in the presence of Cl − give the neutral complexes (η 5 -C 6 H 3 Me 4 )Ru(P(OMe) 3 ) 2 Cl or (η 5 -C 6 H 3 Me 4 )Ru(dppe)Cl, respectively. Cation 1 also exchanges the naphthalene ligand for other arenes producing the corresponding sandwich compounds [(η 5 -C 6 H 3 Me 4 )Ru(arene)] + (arene = C 6 H 6 , 1,4-C 6 H 4 (OMe) 2 ). Complex 1 catalyzes cyclotrimerization of N,N-di(propargyl)tosylamide with 1-octyne or 4-pentynol, but less effectively than [CpRu(C 10 H 8 )] + . The mechanism of the naphthalene replacement in 1 was studied by DFT calculations. [ABSTRACT FROM AUTHOR]

Abstract: Reaction of CpRu(cod)Cl with phenylacetylene and AcOH gives an unusual binuclear ruthenium complex CpRu(μ-σ,η3:η3,σ-C6H3Ph3)RuCp (5, 58% yield) with a bridging acyclic flyover ligand C6H3Ph3. Under similar conditions [CpRu(MeCN)3]+ undergoes an unexpected cleavage of Cp ligand giving 4,7-diphenyl-3a,7a-dihydroindene (6, 65% yield). In sharp contrast, the pentamethylated congeners Cp*Ru(cod)Cl and [Cp*Ru(MeCN)3]+ react with phenylacetylene and AcOH in catalytic fashion giving 1,4-diphenyl-1-acetoxy-1,3-butadiene. The structures of 5 and 6 were established by X-ray diffraction. The mechanism of Cp ligand cleavage was proposed on the basis of DFT calculations. [Copyright &y& Elsevier]

Abstract: The iron complex [(η5-indenyl)Fe(η6-indene)]+ (1) was prepared via one-pot procedure in 25% yield by reaction of FeCl3 with indenyl lithium giving Fe(η5-indenyl)2 and its subsequent protonation with CF3COOH. Cation 1 reacts with 2e ligands L (L= t BuNC, P(OMe)3, P(OEt)3, PMe(OEt)2) under visible light irradiation giving the half-sandwich complexes [(η5-indenyl)FeL3]+ in 50–80% yields. Protonation of the related ruthenium complex Ru(η5-indenyl)2 gives cation [(η5-indenyl)Ru(η6-indene)]+ (23% yield). The structures of [1]BF4 and [(η5-indenyl)Fe( t BuNC)3]PF6 were determined by X-ray diffraction. [Copyright &y& Elsevier]

Abstract: A series of novel hybrid pincer ligands bearing thiophosphoryl and imino groups as donating arms was obtained by the condensation of 3-diphenylthiophosphorylbenzaldehyde with RNH2 (R = Ph, tBu) to afford aldimine derivatives 2a, b or by the reaction of lithiated 3-(thiophosphoryl)bromobenzene with an appropriate substituted lactam yielding their ketimine analogs 2c–e with 5–7-membered azacycloalkene moieties. The direct cyclopalladation of the ligands with (PhCN)2PdCl2 in MeCN under reflux led to κ3-NCS pincer complexes 3b–e with two five-membered fused metallacycles, isolated in low to moderate yields (12–53%); their structures were confirmed by multinuclear NMR and X-ray diffraction study. The palladacycles demonstrated high activity as (pre)catalysts for the Suzuki cross-coupling of phenylboronic acid with aryl bromides, which was found to increase in the series 3e ∼ 3d <3c< 3b, i.e. passing from ketimine derivatives 3d, e with larger azacycloalkene to their analog with smaller five-membered cyclic imine moiety and further to benzaldimine complex 3b. The tendency observed was explained by the controlled release of Pd(0) catalytically active species in the case of less sterically hindered complexes. [Copyright &y& Elsevier]

5,6-Diaryl-2,3-dihydro-1H-pyrazolo[1,2-a]pyrazolium tetrafluoroborates (hexafluorophosphate) were unexpectedly synthesized along with expected 1,3-diaryl-2-nitrotetrahydro-1H,5H-pyrazolo[1,2-a]pyrazoles, under the action of 1-nitro-2-(3-nitrophenyl)-ethylene on 6-aryl-1,5-diazabicyclo[3.1.0]hexanes in ionic liquids with the Et2O·BF3 catalyst, whereas the same reaction with unsubstituted β-nitrostyrene produced only 1,3-diaryl-2-nitrotetrahydro-1H,5H-pyrazolo[1,2-a]pyrazole derivatives. [Copyright &y& Elsevier]

A novel recyclable prolinamide-derived ionic-liquid-supported organocatalyst of asymmetric cross-aldol reactions in aqueous medium is developed. [ABSTRACT FROM AUTHOR]

4-Thio derivatives of sydnone imines were obtained by the reaction of 4-lithiosydnone imines with elemental sulfur and subsequent treatment of the reaction mixture with electrophiles. [Copyright &y& Elsevier]