Abstract The reaction of hydrosilylation of allyl esters XOCH 2 CH= CH 2 (X= MeCO, CF 3 CO, C 3 F 7 CO) and PhOCH 2 CH= CH 2 with hydrosilanes HSiY 3 (Y= Cl, OEt) in the presence of the Speier catalyst, the Speier catalyst with additives, and of various nickel complexes was studied. The catalytic hydrosilylation reaction in the presence of the Speier catalyst is accompanied by the reduction. Additives to the Speier catalyst ( ...