Journal of Chemical Research

The autoxidation of [Ni^II(cyclam)]²⁺ (cyclam = 1,4,8,11 -tetraazacyclotetradecane) and Ni^IItetraglycine, accelerated by S^IV, is studied spectrophotometrically by following the formation of Ni^III complexes.

Unexpectedly high yields of deoxygenation products from the title reactions are observed and rationalized.

Synthesis of flavopereirine 1, formal synthesis of isogeissoschizines 8 and dihydrocorynantheols 9 through the intermediacy of 3-(2-hydroxyethyl)-6,7-dihydroindolo[2,3-a]quinolizine 3 and also the unexpected formation of the β-carbolines 12 and 13 on Huang-Minion reaction of 2 are described.

The 5-acetoxy-4-acetylpyrrole 1 and its derivatives show a range of reactivity towards various aromatic substrates giving pyrroloindoles and pyrrolo [3,2-b] carbazoles amongst other products.

A re-investigation of some complexes of molybdenum claimed to contain coordinated C-nitroso compounds has demonstrated that these solids are complex and that π-coordination of RNO cannot be the sole structural component.

The tetracyanoethylene catalysed methanolysis of 17β-acetoxy-4β,5β:6α,7α-diepoxyandrostane afforded 17β-acetoxy-4α,7α-oxido-5β-hydroxy-6β-methoxyandrostane in which the methanolysis product of the 6α,7α-epoxide has participated in the cleavage of the 4β,5β-epoxide; the reaction is modified however by an adjacent 3β-hydroxy group.

High-grade chloramine is prepared in batch and in continuous mode starting from mixed ammoniacal solutions and hypochlorite at hundred chlorometric degrees.

An efficient synthesis of some novel pyrazoles 8a-j, 13a-e, 18a,b, isoxazoles 26a-g, pyrazolo[3,4-d]pyridazines 9a-d and isoxazolo[3,4-d]pyridazines 27a-d via 1,3-dipolar cycloaddition reactions is reported.

2-Phenyl-3-nitrosoindole activated with PhCOCI reacts with indoles and indolizines (NuH) affording products of 1,2-addiction which undergo 1,3-nucleophilic migration in acid media.

A new synthesis of ferrocene-d₁₀ using acid catalysed exchange is described.

Photobromination of naphthalene with molecular bromine gives only one stereoisomer α,2β,3χ,4β-tetrabromo-1,2,3,4-tetrahydronaphthalene (yield 90%); dehydrobromination of which results in the formation of 1,3-dibromonaphthalene in 88% yield.

The highly reactive 1:1 intermediate produced in the reaction between tert-butyl isocyanide and dialkyl acetylenedicarboxylates is trapped by dialkyl 2-bromomalonates to yield the title compounds in fairly high yields.

Iron(III) 5,10,15,20-tetrakis(pentafluorophenyl) porphyrin, Fe(TF₅PP)CI, is a new catalyst for the conversion of epoxides to the corresponding thiiranes in the presence of ammonium thiocyanate in excellent yields.

A new short synthesis of 7,9-dialkylcyclohepta[b]pyrimido[5,4-d]pyrrole-8(7H),10(9H)-dione derivatives consists of the reaction of 6-amino-1,3-dialkyluracils with tropone, 2-halotropones and 2,6-dibromotropone in an enamine-alkylation process, subsequent condensation of the amino group with carbonyl function, and aromatization under the reaction conditions.

Hydrotalcite is an efficient catalyst for air oxidation of a variety of aromatic, aliphatic and alicyclic thiols in hexane, affording the corresponding disulfides in excellent to quantitative yields under mild and neutral conditions.

The ring-chain tautomer of the α-sulfonyl anion of 1,4-oxathiane S,S-dioxide can be trapped by addition of alkoxides to the vinyl sulfone; the scope of this reaction is explored.

Nonconjugated carboxylic acids are selectively esterified in good yields in the presence of conjugated or aromatic carboxylic acids by stirring over Amberlyst-15 in alcohol at room temperature.

2-Acetyl-5,8-dimethoxy-3,4-dihydronaphthalene is prepared by using a 1,3-dipolar cycloaddition of nitrile oxide to the corresponding dihydronaphthalene.

Protonation of the 1:1 intermediate produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates by pyrrole-2-carbaldehyde leads to a vinylphosphonium salt, which undergoes intramolecular Wittig reaction to produce the title compounds in good yields.

A novel synthesis of 5-amino-1-arylsulfonyl-4-pyrazolin-3-ones via intramolecular cyclization of cyanoaceto-N-arylsulfonylhydrazides is reported and the synthetic potential of the method is demonstrated.

[Rf₂PPd(PhCHO)(Ph₂PCH₂CH₂PPh₂)] + SbF₆^-[Rf =o-C₆H₄C(CF₃)₂0] 5 is prepared by the reaction of Rf₂PPdCI(Ph₂PCH₂CH₂PPh₂) 1 with AgSbF₆ in the presence of benzaldehyde in 92% yield, and the structure determined by X-ray diffraction analysis.

Reaction of Cp(OC)₂Cr=S = Cr(CO)₂Cp with Fe₃(CO)₁₂ affords an encapsulated μ₆-O octahedral Fe₄Cr₂ cluster complex Cp₂Cr₂Fe₄(CO)₁₂(μ₆-O), whose crystal structure is determined by X-ray diffraction analysis.

Condensation reactions of 2,5-dimethoxytetrahydrofuran with p-substituted phenols and 2-naphthol in trifluoroacetic acid produce 1,1,4,4-tetrakis(2-hydroxyphenyl)butane type compounds and 1,2-bis(1,3-dibenzo[a,j]xanthyl)ethane in good yields.

Three component condensation of N,N-dimethylurea, paraformaldehyde and primary amines using montmorillonite K-10 in dry media under microwave irradiation leads to triazones 5a-f in high yields.

Methyl aryl ethers are deprotected in high yields using pyridine hydrochloride in the absence of solvent under microwave irradiation

The biotransformation of (+)-10β,14-dihydroxy-allo-aromadendrane 1 and (-)-allo-aromadendrone 2 by Beauvaria densa CMC 3240, Beauvaria bassiana ATCC 7159, Curvularia lunata 2380 and Rhizopus sp. (from grapes) is investigated.

The regioselective synthesis of isomeric isoxazoles 3-(2-arylcyclopropyl)-5-methylthio- and 5-(2-arylcyclopropyl)-3-methylthio-isoxazoles is described.

Diaryl ketones and chalcones are obtained in good yields by palladium-catalyzed carbonylative coupling of diaryliodonium salts and (E)-phenylethenyl(phenyl)iodonium tetrafluoroborates with potassium aryltrifluoroborates in an atmosphere of carbon monoxide under mild conditions.

Phosphorylation of phenols with diethyl chlorophosphonate on the surface of magnesia is an easy, rapid, safe and high-yielding reaction.

Six-membered cyclic ketones on treatment with acetic anhydride and a catalytic amount of iodine under microwave irradiation give the corresponding enol acetates in good yield.

A simple method for the preparation of pterosin F is described in which the key step involves a tandem reaction of Friedel–Crafts acylation–cycloalkylation between 2,6-dimethylphenethyl chloride and ethyl methacrylate