Fig. 2: Skeletal ring-expansion of indoles with fluoroalkyl N-triftosylhydrazones.
From: Halogencarbene-free Ciamician-Dennstedt single-atom skeletal editing
a Direct carbon-atom insertion of indoles with fluoroalkyl carbenes. Conditions A: indole (0.3 mmol), TFHZ-Tfs (0.36 mmol), TpBr3Cu(CH3CN) (10 mol%), NaH (0.72 mmol) in PhCF3 at 60 °C under N2 for 12 h. Conditions B: indole (0.3 mmol), DFHZ-Tfs (0.6 mmol), TpBr3Cu(CH3CN) (10 mol%), Cs2CO3 (1.8 mmol) in DCM at 40 °C under N2 for 24 h. b Defluorinative carbon-atom insertion of indoles with fluoroalkyl carbenes. Conditions C: indole (0.3 mmol), N-triftosylhydrazone (0.6 mmol), TpBr3Cu(CH3CN) (10 mol%), NaH (1.8 mmol) in PhCF3 at 60 °C under N2 for 12 h. Isolated yields.
