Naphthalene-2-carboxaldehyde

Naphthalene-2-carboxaldehyde forms the naphthyl-2-azabuta-1,3-diene (96) on treatment with l-aminoprop-2-ene followed by base catalysed isomerisation of the unconjugated azadiene. I rolysis brings about an electrocyclisation to the 1.2-dihydrobenzo... 

A versatile and regioselective synthesis of benzo[b]furans, naphthalenes, indoles and benzothiophenes was achieved by reaction of o-alkynylarene and heteroarene carboxaldehyde derivatives in the presence of iodonium ions. The reaction mechanism was also discussed <06CEJ5790>. 

Diamino-2,l>3-benzothiadiazole 201 undergoes cyclization on reaction with selected aromatic aldehydes <2004T2953>. Thus, reactions with pyrene-l-carboxaldehyde or naphthalene-1-carboxaldehyde in refluxing toluene produce the corresponding imidazoles 202 in moderate yields, whereas reactions with /i-(Ar,Ar-dimethylamino)benz-aldehyde and /i-[Ar,Ar-di(4-methylphenyl)amino]benzaldehyde under similar conditions gave the corresponding 5-imino derivatives 203 (Scheme 13). 

CAN-mediated nitration provides a convenient route for the introduction of a nitro group into a variety of substrates. Alkenes on treatment with an excess of sodium nitrite and CAN in chloroform under sonication afford nitroalkenes. When acetonitrile is used as the solvent, nitroacetamidation occurs in a Ritter-type fashion. However, the attempted nitroacetamidation of cyclo-pentene-1 -carboxaldehyde under similar conditions resulted in the formation of an unexpected dinitro-oxime compound. A one-pot synthesis of 3-acetyl- or 3-benzoylisoxazole derivatives by reaction of alkenes (or alkynes) with CAN in acetone or acetophenone has been reported. The proposed mechanism involves a-nitration of the solvent acetone, oxidation to generate the nitrile oxide, and subsequent 1,3-dipolar cycloaddition with alkenes or alkynes. The nitration of aromatic compounds such as carbozole, naphthalene, and coumarins by CAN has also been investigated. As an example, coumarin on treatment with 1 equiv of CAN in acetic acid gives 6-nitrocoumarin in 92% yield. ... 

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