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.
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.