The protocol was found to be scalable. On 5 mmol scale, 3l could be prepared without significant loss in synthetic efficiency or stereoselectivity (1.52 g isolated, 92% yield, 98% ee). In addition, a series of derivatization reactions could be carried out on 3l, 5b and 4c to deliver products 9a, 24a 9b, 7a,8q and 9c 24b with high levels of stereoselectivity, enantiospecificity, and regiospecificity, respectively. Notably, comparison of chiral HPLC retention times and optical rotation of 9b with those reported in the literature allowed the absolute configuration of silane 5b to be deduced and those of other enantioenriched silane products 3 and 5 to be assigned by analogy. Furthermore, vinyl silane 5a bearing a stereocenter at the propargylic position could undergo CuH-catalyzed hydroamination with catalyst control of diastereoselectivity. 8h We performed a series of experiments to probe the mechanism of this iridium-catalyzed process. We began by examining the kinetic isotope effect using 1-phentyl-1-butyne (1a) and its deuterated isotopologue (1a-d5). Initial rate experiments conducted in parallel yielded a kH/kD of 8.51±0.44, and an intermolecular competition experiment resulted in a KIE value of 8.94±0.21. The close agreement of the primary kinetic isotope effect measured in these two sets of experiments suggests an irreversible and turnover limiting proton abstraction step (Scheme 3A). We then sought to determine the kinetic order of each of the reagents and the catalyst by varying the concentration of each component (alkyne 1a, [Ir]/L1 (L1:Ir = 2:1), TMPH, and TESOTf) and measuring initial rates of reaction to provide silylation product 3a (Scheme 3B). These experiments revealed first order dependence on catalyst, base, and silyl triflate but zero order dependence on the alkyne. Stoichiometric NMR experiments demonstrate that, in the presence of alkyne, silyl triflate reagents abstracts Cl -completely from the phosphoramidite-ligated Ir center within 10 min to generate the cationic alkyne complex II (Scheme 4, see the Supporting Information). 25c Moreover, 31 P NMR analysis of the reaction mixture indicates that II is the major phosphorus-containing species during the course of the reaction (up to 50% conversion). These observations suggest that complex II is the catalyst resting state and are consistent with the zero order kinetic dependence on [1a]. To account for the first order dependence on [TESOTf], we propose that II engages the silylation reagent before deprotonation takes place.