Allyl glycidyl ether was underwent hydrosilylation with triethoxysilane or hydrosiloxane over a Karstedt Pt complex [Pt-2{(CH2=CHSi(Me-2)(2)O}(3)], or [Pt(PPh3)(2)C2H4], or H2PtCl6 in cyclohexanone, or a Speier catalyst at >100degreesC to yield (50-75%) 3-glycidoxypropyltriethoxysilane. Much more active was a bis(1,5-cyclooctadiene)-di-(mu-trimethylsiloxy)di-rhodium(I) complex which at room temperature gave the product in 90+% yield. Reactants could be mixed directly, reaction time was cut from 24 to 2 h, no overheating occurred, but the Rh amount was 10 times (at 60degreesC, 5 times) as great as that of the Karstedt catalyst.