A new approach to the synthesis of functionalized pyrido[2,3-b]indoles by way of a palladium-catalyzed ring closing reaction between the N-1 and C-9a positions

✍ Scribed by Ahmed Abouabdellah; Robert H. Dodd

• Publisher: Elsevier Science
• Year: 1998
• Tongue: French
• Weight: 238 KB
• Volume: 39
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(98)00065-3

✦ Synopsis

The enolate of 4-N-(tert-butyloxycarbonyl)aminobutyro-7-lacto~e 9 reacted with 2-bromo-1methylindole-3-carboxaldehyde it, the presence of stannic chloride to give the product of aldol condensation 16. Deprotection and dehydration of the latter with trifluoroacetic' acid and dimethyl sulfide followed by Pd2(dba)3 -catalyzed ring closing of the product afforded the ot-earboline 6 in good overall yield.