Cyclopalladation and metaloxylation of 1-(phenylazo)-2-hydroxynaphthalene

✍ Scribed by Rupa Bhawmick; Pinaki Bandyopadhyay

• Publisher: Springer
• Year: 1995
• Tongue: English
• Weight: 106 KB
• Volume: 20
• Category: Article
• ISSN: 0340-4285
• DOI: 10.1007/bf00139145

✦ Synopsis

Cyclometallation is an important method for regioselective activation and functionalization of carbon-hydrogen bonds. Cyclopalladated compounds are useful reagents in organic syntheses ~1-7). We present here our findings on the cyclopalladation and functionalization of 1-(phenylazo)-2-hydroxynaphthalene via metaloxylation (C--Pd , C--O--Pd) ~8-1~ A mixture of 1-(phenylazo)-2-hydroxynaphthalene and disodium tetrachloropalladate(II)(1 : 1 molar ratio) in aqueous EtOH (1:9) was stirred for 10 days at room temperature. The filtrate was collected and evaporated to dryness, the solid mass was thoroughly washed with benzene and CHzC1 e. Addition of 4-picoline to a suspension of the residue in CH2C12 resulted in a deep green solution of complex (1). After filtration, the volume of the filtrate was reduced in vacuo and complex (1) was collected as deep green crystals (10% yield).