On the [42]Cycloaddition Approach to Indolo[2,3-a]carbazoles
摘要:
2,2'-Biindolyl 9 reacts with electron-deficient dienophiles at 100-110 degrees C to give low to moderate yields of Michael addition and formal [4 + 2] cycloaddition products, with the former predominant; the products derived from 9 and 2-(phenylsulphinyl)maleimides 14 and 15 undergo in situ elimination of benzenesulphenic acid, leading to 2,2'-biindolyl-substituted maleimides which can be efficiently photocyclised into indolo[2,3-a]carbazoles.
SmI2-Promoted novel tandem elimination and coupling reactions of aliphatic imides with carbonyl compounds: application to the synthesis of dl-isoretronecanol
Treatment of α-hetero-substituted cyclic imides with carbonylcompounds mediated by samarium(II) diiodide in the presence of HMPA was found to undergo novel tandem elimination and reductive coupling reactions to generate α-hydroxyalkylated imides in good to high yields. Stereochemistry of the coupling products was researched and the result that increasing the steric bulkiness of the N-substituents