Pd(O), generated in-situ, in combination with TIOAc promotes a range of catalytic bi- and tri-molecular cycloadditions of aryl/heteroaryl iodides in which carbon monoxide (1 atm) functions as a one carbon component furnishing 5 - 7 membered rings in good yield.
Grigg Ronald, Khalil Hashim, Levett Philip, Virica Julia, Sridharan Visuv+, Tetrahedron Lett, 35 (1994) N 19, S 3197-3200