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By six examples, it was demonstrated that nitrosylsulfuric acid can be successfully used for oxidation of 3,5-diaryl-4,5-dihydroisoxazoles to the corresponding 3,5-diarylisoxazoles. If the starting isoxazolines contain the aromatic substituents activated towards electrophilic substitution, nitration of both newly formed isoxazole and substituted benzene rings occurred. [ABSTRACT FROM AUTHOR]

Reactions of potassium dihaloiodates with arylcyclopropanes and polycyclic compounds containing a cyclopropane fragment characterized by different degrees of strain lead to formation of mixed 1,3-halogenation products. If iodohalogenation should give rise to products having a iodine atom in the benzylic position, 1,3-dichloro or 1,3-dibromo derivatives are formed. Iodohalogenation of exo-tricyclo[3.2.1.0]octane is stereoselective and is accompanied by Wagner-Meerwein rearrangement. [ABSTRACT FROM AUTHOR]

Nitrosonium hexachlorostannate (NO)[SnCl] was synthesized by the reaction of NOCl and SnCl in CHCl. According to the single-crystal X-ray diffraction analysis data, the structure of (NO)[SnCl] consists of cations NO and octahedral anions [SnCl] arranged as ions in antifluorite. Isoxazolines were synthesized by the reactions of (NO)[SnCl] with arylcyclopropanes containing donor substituents in the aromatic ring. [ABSTRACT FROM AUTHOR]

A new procedure was proposed for activation of areneselenenamides with phosphorus(V) and sulfur(IV) oxyhalides. According to the 1H, 13C, and 31P NMR data, areneselenenamide reacts with phosphorus oxyhalide to form intermediate adduct in which the phosphorus atom is coordinated at the selenium. Areneselenenamides activated by phosphorus(V) oxyhalides react with alkenes (norbornene and norbornadiene) with high trans-stereoselectivity. Their reactions with terminal olefins are regioselective, and they lead to preferential formation of the corresponding Markovnikov adducts. [ABSTRACT FROM AUTHOR]

The reaction of phenylcyclopropanes substituted in the three-membered ring with nitrosyl chloride activated with sulfur(IV, VI) oxides provided in good yield substituted 5-phenylisoxazolines as a mixture of structural isomers. [ABSTRACT FROM AUTHOR]

Reactions of alkynelsufenamides with olefins (such as cyclohexene, norbornene, 1-hexene, 1-octene, allylbenzene, and styrene) in the presence of phosphoryl halides (POCl3, POBr3) afforded 70–95% of β-halo-substituted alkyl alkynyl sulfides. The reactions with cyclohexene and norbornene are characterized by trans stereoselectivity. Alkynylsulfenylation of terminal alkyl- and benzylacetylenes occurs in a regioselective fashion with predominant formation of the corresponding anti-Markownikoff adducts, while the addition to styrene yields halogen-containing sulfides according to the Markownikoff rule. [ABSTRACT FROM AUTHOR]

Some previously unknown acetamino derivatives were synthesized by the Ritter reaction from ketones of the adamantane and oxahomoadamantane series. The presence of a hydroxy group as substituent in adamantan-2-one gives rise to formation of acetamino derivatives as products of replacement of the hydroxy group and transformation of the carbonyl group. [ABSTRACT FROM AUTHOR]

The direction of trifluoroacetylation with trifluoroacetic anhydride of 3,4-dihydropyrrolo[1,2-a]pyrazines containing an alkyl or aralkyl substituent in position 1 depends on both the structure of the 3,4-dihydropyrrolo[1,2-a]pyrazine starting materials and on the ratio of reagent:substrate. It may lead to both mono- and disubstituted products. Trifluoroacetylation of 1-methyl-3,4-dihydropyrrolo[1,2-a]pyrazines occurs at the methyl group. Acetylation of 3,4-dihydropyrrolo[1,2-a]pyrazines leads only to N-acetyl-substituted reaction products. [ABSTRACT FROM AUTHOR]

A series of previously unreported aldehydes has been prepared by the formylation reaction of dipyrrolo[1,2-a;2':,1'-c]pyrazines and their 5,6-dihydro analogs by DMF and phosphorus oxychloride. [ABSTRACT FROM AUTHOR]

We have studied the behavior of asymmetrically substituted dipyrrolo[1,2-a;2',1'-c]pyrazines and their 5,6-dihydro analogs under phosphorylation reaction conditions. [ABSTRACT FROM AUTHOR]

The reactions of 2-phenylpropanal with ethyl hydrogen malonate and benzylamine (or benzylammonium acetate) and of ethyl 4-phenyl-2-pentenoate with benzylamine take different pathways, depending on the conditions. [ABSTRACT FROM AUTHOR]

A preparation is reported of some previously unknown 1,4-disubstituted adamantane derivatives containing a phenylisoserine fragment. [ABSTRACT FROM AUTHOR]

The presence of the electron donating groups complicates the reaction. [ABSTRACT FROM AUTHOR]