Key points are not available for this paper at this time.
2-Bromobenzaldehydes react with arylhydrazines in toluene at 100 degreeC in the presence of a catalytic amount of a palladium catalyst and phosphorus chelating ligands such as 1,1prime or minute-bis(diphenylphosphino)ferrocene and 1,3-bis(diphenylphosphino)propane along with NaO-t-Bu to afford 1-aryl-1H-indazoles in good yields.
Cho et al. (Fri,) studied this question.