Reagents containing carbon–tin–halogen inter-element linkages were effective for palladium-catalyzed carbostannylation. In situ generated allyltin trichlorides add to carbon–carbondoublebonds of bicyclo[2.2.1]hept-2-ene (norbornene) and bicyclo[2.2.1]hepta-2,5-diene (norbornadiene), stereoselectively, under the catalysis of palladium(0) species in good yields. The regioselectivity of unsymmetrically