Isatins with carbon nucleophiles

Reactions of Phosphines. - 1.2.1 Nucleophilic Attack at Carbon. Interest has continued in developing the synthetic applications of the 1 1 adducts of tertiary phosphines with dialkyl acetylenedicarboxylate esters. Protonation of the initial adduct from triphenylphosphine by phthalimide, followed by nucleophilic addition of the nitrogen of the resulting imido anion to the intermediate vinylphosphonium salt, has given the stabilised ylide system (189). ° Similar reactions with isatin and 3-chlorotetrahydrofuran-2,4-dione have given the yl-... 

Recently, Chi and coworkers reported the NHC-catalysed p-functionalisation of carboxylic anhydrides.The P-carbon behaved as a reactive nucleophilic carbon and underwent asymmetric reactions with electrophiles such as all lidene diketones, chalcones and isatins to give the desired p-carbon functionalised products 228-230 in good yields and with excellent diastereo-and enantioselectivities (Scheme 20.91). 

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