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NUCLEOPHILIC DISPLACEMENT OF THE METHOXY GROUP IN 5-METHOXYISOXAZOLE
No full textThe reaction of 5-methoxy-3-phenylisoxazole, 1a, with primary and secondary alcohols in the presence of acids gives 5-alkoxy derivatives 1b-d in almost quantitative yields
Reactions between nitrile oxides and carbenium ions: synthesis of benzoxazines, oximes and amides through intramolecular ortho and ipso attack
No full textReactions between nitrile oxides and benzylic carbocations are described. Different results were obtained when the carbocations were generated from the corresponding chlorides with different Lewis acids, with addition products such as benzoxazines, oximes, and amides being produced. Primary, secondary, and tertiary carbocations showed different reactivities. The product ratios strongly depended on the substituents on the aromatic ring of the benzylic carbocations. Evidence for the proposed mechanism is reported
New reactions of furoxans: Formation of alkynes and cyclobutaphenanthrenes
No full textDiarylfuroxans were found to give diaryacetylenes upon irradiation at 254 nm. Cyclobutaphenanthrenes were also obtained when reaction was carried out in the presence of alkenes. The acetylenic derivative is supposed to arise by loss of (NO)2 from a diazete-N,N-dioxide. Unimolecular and collision activated dissociation studies by tandem mass spectrometry also support the loss of (NO)2 from diarylfuroxans molecular ions
Selective hydrolysis of glycerol carbonate esters by silica gel under microwave irradiation
No full textNitrile Oxide-BF3 complex as electrophilic moiety towards aromatic systems: Stereospecific synthesis of oximes
No full textAromatic Oximes are obtained stereospecifically by action of Nitrile Oxide-BF3 complexes on Aromatic Compounds
New aspects of nitrile oxides chemistry
No full textReactivity of nitrile oxides (1) towards both dimerization and cycloaddition with dipolarophiles can be inhibited by catalytic amount of tris-(4-bromophenyl)-aminium hexachloroantimonate and subsequently restored
Iron dichloride induced isomerization or reductive cleavage of isoxazoles: A facile synthesis of 2-carboxy-azirines
No full text5-Alkoxy-isoxazoles and N,N-disubstituted-5-isoxazolamines were found to isomerize to azirine derivatives by the use of iron dichloride as catalyst. On the contrary 5-alkyl- and 5-aryl-isoxazoles in the presence of the same salt, undergo reductive cleavage to enaminoketones. A common reaction intermediate is proposed
Un approccio alternativo a biocombustibili a partire da oli vegetali: sintesi di esteri del carbonato del glicerolo (GCE) da oli e tricarbonato del glicerolo
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