Regioselective synthesis of N-aminoisoindolones and mono-N- and di-N,N'-substituted phthalazones utilizing hydrazine nucleophiles in a palladium-catalyzed three-component cascade process.

A palladium-catalyzed three-component cascade process for the synthesis of isoindolone and phthalazone derivatives is reported. The cascade process involves carbonylation of an aryl iodide/Michael acceptor to give an acylpalladium species which is intercepted by a hydrazine nucleophile. Intramolecular Michael addition follows to give either N-aminoisoindolones or mono- N- and di-N,N'-phthalazones depending on whether a monosubstituted or 1,2-disubstituted hydrazine nucleophile is used.

Triol protection with 6-benzoyl-3,4-dihydro-(2H)-pyran.

6-Benzoyl-3,4-dihydro-(2H)-pyran will protect 1,2,3-triols such as glycerol as their corresponding spiro-[5-phenyl-3,6,8-trioxabicyclo[3.2.1]octane-4,2[prime or minute]-tetrahydropyran]s and 1,2,4-triols (less efficiently) as the corresponding trioxabicyclo[3.2.2]nonanes; the hexol mannitol is converted into the corresponding bis-protected product.