Mild and Efficient Syntheses of 1-Aryl-3,4-dihydroisoquinolines and 1-Aryl-3,4-dihydro-β-carbolines via Regiospecific β-Eliminations of the CorrespondingN-Tosyl-1,2,3,4-tetrahydroisoquinolines andN-Tosyl-1,2,3,4-tetrahydro-β-carbolines
摘要:
Treatment of N-tosyl-1-aryl-1,2,3,4-tetrahydro-isoquinolines or N-tosyl-1-aryl-1, 2,3,4-tetrahydro-beta-carbolines with a strong base such as NaOH or KOH at 70 degrees C in dimethylsulfoxide (DMSO) produced 1-aryl-3,4-dihydroisoquinolines or 1-aryl-3,4-dihydro-beta-carbolines in good yields via mild and regiospecific beta-eliminations. A dramatic solvent effect was observed, DMSO was crucial for the reactions. The temperature is also crucial for the reactions and should be kept between 60 and 80 degrees C.
Efficient and Practical One-Pot Conversions of N-Tosyltetrahydroisoquinolines into Isoquinolines and of N-Tosyltetrahydro-β-carbolines into β-Carbolines through Tandem β-Elimination and Aromatization
An efficient, practical, and general method for conversions of N-tosyltetrahydroisoquinolines (N-tosyl-THIQs) into isoquinolines and of N-tosyltetrahydro-β-carbolines (N-tosyl-THBCs) into β-carbolines is described. Treatment of N-tosyl-THIQs or N-tosyl-THBCs with base in dimethyl sulfoxide afforded dihydroisoquinolines or dihydro-β-carbolines as intermediates, and these were then oxidized in situ by
A Novel Access to Tetrahydro-β-Carbolines via One-Pot Hydroformylation/Fischer Indole Synthesis: Rearrangement of 3,3-Spiroindoleninium Cations
作者:Bojan P. Bondzić、Peter Eilbracht
DOI:10.1021/ol801071y
日期:2008.8.21
The two component one-pot hydroformylation/Fischer indole synthesis sequence of 2,5 dihydropyrroles and phenyl hydrazines allows a facile and convenient access to tetrahydro-beta-carbolines in moderate to good yields.