6-Halogenofulvenes and allylcyclopentadiene from nickelocene

In the presence of triphenylphosphine, nickelocene reacts with tetrachloromethane to give (trichloromethyl)cyclopentadiene, which can be dehydrohalogenated to 6,6-dichlorofulvene. It reacts analogously with tetrabromomethane and (trichloromethyl)benzene. 3-Bromopropene reacts with nickelocene to give allylcyclopentadiene.     

Furanolates 1. A General Preparation of Alkyl Furyl Carbonates

Trimethylsiloxyfuran reacts with methyllithium to give lithium fura-nolate and unreactive tetramethylsilane, the former reacts with alkyl chloroformates on oxygen to give alkyt furyl carbonates not previously easily prepared.     

Reactions of Podophyllotoxin with DDQ

Introduction 2, 3-Dichloro-5, 6-dicyanobenzoquinone (DDQ) can react with lignans of the mono- arylidene-butyrolactone1, aryltetralin2, dibenzylbutane3 and aryltetralin-butyrolactone4,5 series. We have studied the reactions of this reagent with podophyllotoxin 1, which is a well-known natural product on account of its long history of use in folk medicine and the biological activity of its many derivatives6. In particular, derivatives of 4-demethyl epipodophyllotoxin are used in cancer chemo…     

Synthesis of novel functionally substituted pyridazines and oxazines

Acetone 1,3-di(phenylhydrazone) reacts with arylidenemalononitriles in the presence of piperidine to give the coressponding 3,3′-carbonylbispyridazine derivatives. Under the same reaction conditions dioxime reacts with arylidenemalononitriles to give the corresponding 3,3′-carbonylbis-1,2-oxazines. Dioxime reacts with primary aromatic amines and formalin in a molar ratio of 1:1:2 to give 1-arylidene-3,5-dihydroxyimino-piperidine-4-ones. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1223–1229, August, 2008.     

Chemistry of geminal-dithiolates derived from cyano-substituted tetrathiafulvalenes

Tetracyanotetrathiafulvalene reacts with two equivalents of thiol salts (RS^?) to give 1,2-dicyano-1,2-di RS ethene and a geminal dithiolate intermediate which reacts with a variety of reagents to provide novel tetrathioethene derivatives, such as reaction with 3-chloro-2-butanone and acid to give dimethyldicyanotetrathiafulvalene.     

Nitroso compounds : III. The reaction of bromomagnesium diphenylcuprate and phenylcopper reagents with nitrosobenzene

Bromomagnesium diphenylcuprate reagent reacts with nitrosobenzene to give diphenylhydroxylamine, biphenyl, diphenylamine, azoxybenzene and phenol. It reacts with alkyl nitrites to give the above products as well as the corresponding alkanols. Phenylcopper reagent behaves similarly but somewhat sluggishly. A mechanism involving an initial electron-transfer process is proposed.     

Heterocyclic bioantioxidants 4. Chlorolysis of 3-nitro-4-s-benzylcoumarin

3-Nitro-4-S-benzylcoumarin reacts with sulfuryl chloride to give an unstable compound, which in turn reacts with p-toluidine to give 3-nitro-4-p-tolylaminocoumarin.For Communication 3, see [1].Translated from Khimiya Geterotsiklicheskikh Soednenii, No. 7, 888–889, July, 1992.     

Pyridazine Derivatives and Related Compounds,Part 1. Some Reactions with 4-Cyano-5,6-Diphenyl-2,3-Dihydropyridazine-3-One

4-Cyano-5,6-diphenyl-2,3-dihydropyridazine-3-onc 1 reacts with phosphorous oxychloride to give 70% of the corresponding 3-chloro derivative 2. Treating 2 with anthranilic acid in butanol, 4-cyano-2,3-diphenyl-10H-pyridazino[6,1-b]quinoxaline-10-one, 3 was obtained. Compound 1 reacts with phosphorous pentasulphide to give 3-mercapto derivative 4, which was converted by acrylonitrile to S-(2-cyanoethyl)pyridazine derivative 5. Compound 4 reacts with ethyl bromoacetate and with phenacyl bromide gave the corresponding thieno[2,3-c] pyridazine derivatives 8, 9, Alkylation of 1 with ethyl chloroacetate afforded 3-0-carbethoxymethyl derivative 10. Compound 10 reacts with amines (aniline, hydrazine) to give the corresponding amide and acid hydrazide 13, 12 respectively. Hydrolysis of 10 with sodium hydroxide gave the corresponding acid derivative 11. Treating 1 with methyl iodide, 3-0-methyl derivative 14 was obtained, which was converted by ammonium acetate/acetic acid to 3-amino-4-cyano-5,6-diphenyl pyridazine 15. Compound 1 reacts with methyl magnesium iodide gave 4-acetyl derivative 16, which was reacted with hydrazine, phenyl hydrazine and with hydroxylamine to give the substituted I H pyrazolo [3,4-c] pyridazine 17 a,b and isoxazolo [5,4-c] pyridazine 18 derivatives respectively.     

Action comparée de l'eau oxygénée et d'un peracide sur un sel d'immonium pyrrolinique stéroïdique et sur l'énamine correspondante. Formation et propriétés d'un sel d'oxaziridinium

The reaction of a pyrrolinium salt with a peracid affords an oxaziridinium salt. The corresponding enamine reacts similarly to give products oxidized at the α-position to the nitrogen atom. These results are rationalized in terms of the formation of an intermediate oxaziridinium ion. The oxaziridinium salt reacts with nucleophiles to give either an carbinol iminium salt or products resulting from oxygen transfer.     

Hydride shift reactions with the participation of two-ring sulfides

2,3-Dihydrobenzothiophenes are dehydrogenated to the corresponding benzothiophenes on reaction with the hydride-ion acceptors triphenylmethyl tetrafluoroborate and chloranil. Thiochroman reacts with chloranil to give 2-methyl-2,3-dihydrobenzothiophene and 2-methylbenzothiophene and reacts with triphenylmethyl tetrafluoroborate to give a thiochromenylium salt.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 328–330, March, 1976.     

Heterocycles of biological importance. Part 2. Novel synthesis and pharmacological evaluation of 5-amino-3-alkyl-1-(2-pyridyl)pyrazoles and 5-amino-3-phenyl-1-(2-pyridyl)pyrazole from allenic or acetylenic nitriles and 2-hydrazinopyridine

2-Hydrazinopyridine reacts with allenic and acetylenic nitriles to give 5-amino-3-alkyl-1-(2-pyridyl)pyrazoles 6 in excellent yields. One of these compounds, 6e has been shown to possess anticonvulsant and anti-electroshock properties. Phenyl propynenitrile also reacts with hydrazinopyridine to give 5-amino-3-phenyl-1-(2-pyridyl)pyrazole ( 11 ) in quantitative yield.     

Reactions of diborane with organic derivatives of tin and lead

Diborane reacts with aryltin and aryllead compounds to give intermediates which on hydrolysis give arylboronic and arylborinic acids, and on oxidation give phenols.     

Reaction of vanadium(v) complexes with some adduct-forming substances in benzene

Vanadium(V) reacts with monobasic and bidentate extracting agents, i.e. 8-quinolinol, 2-methyl-8-quinolinol, salicylaldoxime, hinokitiol, benzoylphenylhydroxylamine, maltol, cupferron, dibenzoylmethane, salicylaldehyde, and phenylmethylbenzoylpyrazolone-5, to form 1:2 complexes containing a basic V=O group and an acidic V—OH group in the same molecule. The basic group reacts with acidic substances to give a hyper- and bathochromic effect; the acidic group reacts with basic substances to give a hyper- and hypsochromic effect. These reactions are observed in benzene solutions.     

Lewis acid mediated allylation of 2-alkanoyl-1,4-quinones with allylsilane and allylstannane

Allyltrimethylstannane reacts uith 2-alkanoyl-1,4-quinones regioselectively to afford conjugate addition products which can be derived to 2-alkanoyl- 3-allylhydroquinone diacetate, while allyltriphenylsilane reacts with the quinone to give naphthofuran.     

Reaction of carbenes with bicyclo[2.1.0]pentane

Bicyclo[2.1.0]pentane reacts with phenylcarbene and dicarbomethoxycarbene by simple insertion at the cyclobutane methylene position. By contrast, difluorocarbene reacts by two bond cleavage to give 1,1-difluoro-1,5-hexadiene.     

Synthesis and properties of 3-thiono derivatives of pyrido[2,3-e]-asym-triazine

2-Amino-3-hydrazinopyridine reacts with carbon disulfide to give 1,2,3,4-tetrahydropyrido[2,3-e]-asym-triazine-3-thione. The methylthio derivative obtained from it is oxidized to the sulfone, which undergoes exchange of the methylsulfonyl group for an amine residue in the cold. The methylthio derivative undergoes this sort of reaction only on heating, whereas in the cold it reacts with amines to give adducts that are unstable in solution and on heating.     

Reaction of pyrazine-2,3-dicarbonitrile and 1,3-dimethyllumazine with alkyl radicals

Pyrazine-2,3-dicarbonitrile ( 1 ) reacts with alkyl radicals to give mono- 3 and di-alkylated pyrazine-2,3-dicarbonitriles 4 . Similarly 1,3-dimethyllumazine ( 2 ) reacts with alkyl radicals to give 7-alkyl-1,3-dimethyllumazines 8 as the major product. The reactivity of alkyl radicals decreases in the order tertiary, secondary, and primary, and 1 is more reactive than 2 in those radical substitution reactions.     

Formation and characterization of mononuclear and dinuclear manganese oxide-dioxygen complexes in solid argon

A manganese atom reacts with dioxygen to form the previously characterized MnO 2 molecule in solid argon under UV-visible light irradiation. Subsequent sample annealing allows the dioxygen molecules to diffuse and to react with MnO 2 to give the (eta (2)-O 2)MnO 2 complex, which is characterized to be a side-on bonded peroxo manganese dioxide complex. The manganese tetraoxide MnO 4, which was predicted to be less stable than the (eta (2)-O 2)MnO 2 isomer, was not observed. However, the (eta (2)-O 2)MnO 2 complex reacts with another weakly coordinated dioxygen to give the (eta (2)-O 2)MnO 4 complex via visible light irradiation, in which the manganese tetraoxide is coordinated and stabilized by a side-on bonded O 2 molecule. Manganese dimer reacts with dioxygen to form the cyclic Mn(mu-O) 2Mn cluster spontaneously upon annealing, which further reacts with dioxygen to give the (eta (2)-O 2) 2Mn(mu-O) 2Mn cluster, a side-on bonded disuperoxide complex with a planar D 2 h structure.     

Reactions of hexamethyldilead with 7,7,8,8-tetracyanoquinodimethane (TCNQ) and tetracyanoethylene (TCNE)

Hexamethyldilead reacts with TCNQ to give Pb(TCNQ)₂ and tetramethyllead and with TCNE to give Pb(TCNE).     

Nitrogen extrusion from pyrazoline-substituted porphyrins and chlorins using long wavelength visible light

Protoporphyrin reacts with diazomethane to give pyrazolines which at long wavelength (approximately 630 nm) extrude nitrogen to give the corresponding cyclopropyl derivatives.