For this purpose, we synthesized 1-heptafluoropropylnaphthalene ( ) and 1nonafluorobutylnaphthalene (8) and tested their reactivity. The reaction of 7 with 14 equivalents of hydrosilane and K3PO4 resulted in poor conversion of the starting material (~30%), which prompted us to test the reaction at a higher temperature. At 120 °C, 7 was fully converted and a small amount of fully hydrodefluorinated product 9 was detected. Under these conditions, fluorosilane 6 was detected in 62% yield. Furthermore, the reaction of 8 with 18 equivalents of hydrosilane gave a small quantity of the exhaustively hydrodefluorinated product 10 together with fluorosilane 6 in 50% yield.