Variation of the N-protecting group of diazooxindoles was permissible with the corresponding products being formed in good yields under both conditions (3-8). A diverse array of diazooxindoles bearing a single electron-donating (methyl and methoxy) or electron-withdrawing (halogen and nitro) substituent at random position of the aryl ring all participated well in the reaction under both conditions to furnish the target products 9-26 in 45-91% (condition A) and 33-75% yields (condition B), respectively. Moreover, diazooxindoles with multi-substituted aryl groups and bulky naphthyl ring also successfully underwent this transformation under both conditions (27-29). In these cases, copper generally exhibits lower catalytic activity than rhodium. In addition to diazooxindoles, other diazo compounds including 1diazo-2-indanone, 3-diazobenzofuranone and 3diazobenzo [b]thiophenone proved to be viable reaction partners, giving rise to the corresponding spiro-products 30-32. In these cases, rhodium is much more superior than copper catalyst.