Thirty Years of (TMS)₃SiH: A Milestone in Radical-Based Synthetic Chemistry

Abstract

This review is an update on tris(trimethylsilyl)silane, TTMSS, in organic chemistry, focusing on the advancements of the past decade. The overview includes a wide range of chemical processes and synthetic strategies under different experimental conditions, including functional group insertion and transformations, as well as preparation of complex molecules, natural products, polymers, surfaces, and new materials. These results reveal how TTMSS has matured over the past 30 years, and they further establish its value as a free radical reagent with widespread academic and industrial applications.

Towards Visible‐Light Photocatalytic Reduction of Hypercoordinated Silicon Species

“…Over the last few decades, organosilicon compounds have received a great deal of attention in organic synthesis, and particularly radical synthetic chemistry, with the generation of transient silicon‐centered radicals from silyl hydrides, behaving both as an effective mediator of radical reactions starting from a range of radical precursors (halides, chalcogens, xanthates, etc …) and as substrates for radical functionalization such as the hydrosilylation of unsaturated systems . The homolytic Si−H cleavage can be obtained for instance with the (TMS) 3 SiH Chatgilialoglu ’s reagent or the Et 3 SiH/RSH system for polarity reversal catalysis introduced by Roberts . More anecdotal, silyl radicals can be generated by photolysis of a Si−B bond for the silylboration of olefins or by photocatalytic oxidation of the supersilanol (TMS) 3 SiOH to perform halogen abstraction for Nickel/photoredox sp 3 ‐sp 3 cross‐coupling reactions .…”

Dehydrogenative Silylation of Alkenes for the Synthesis of Substituted Allylsilanes by Photoredox, Hydrogen‐Atom Transfer, and Cobalt Catalysis

“…By employing TTMSS as the silane reagent, ar ange of electrophilic alkenes successfully participated in this silicon radical addition/dehydrogenation protocol. We were pleased to find that both acyclica nd cyclic unsaturated dialkylamides were well tolerated in this transformation (8)(9)(10)(11)(12)(13)(14)(15). Thep resence of the N À Hb ond in 5 appeared to give as lightly lower yield.…”

“…[10] As shown in Table 1, we began our investigation by screening reaction conditions for the dehydrogenative silylation using TTMSS [BDE(Si-H) = 82.3 kcal mol À1 ]a st he silicon radical precursor.T oo ur delight, the desired allylsilane product 1 (in ay ield of 40 %) was obtained at room temperature by irradiation with blue LEDs using Ir[dF(CF 3 )ppy] 2 (dtbbpy)PF 6 as the photocatalyst, quinuclidine (A)a st he HATc atalyst, Co(dmgH) 2 PyCl (II)asthe protonreduction catalyst, and N-methyl-N-phenylmethacrylamide as the silyl radical acceptor (entry 1). [10] As shown in Table 1, we began our investigation by screening reaction conditions for the dehydrogenative silylation using TTMSS [BDE(Si-H) = 82.3 kcal mol À1 ]a st he silicon radical precursor.T oo ur delight, the desired allylsilane product 1 (in ay ield of 40 %) was obtained at room temperature by irradiation with blue LEDs using Ir[dF(CF 3 )ppy] 2 (dtbbpy)PF 6 as the photocatalyst, quinuclidine (A)a st he HATc atalyst, Co(dmgH) 2 PyCl (II)asthe protonreduction catalyst, and N-methyl-N-phenylmethacrylamide as the silyl radical acceptor (entry 1).…”

Dehydrogenative Silylation of Alkenes for the Synthesis of Substituted Allylsilanes by Photoredox, Hydrogen‐Atom Transfer, and Cobalt Catalysis

“…Substrates with substituted phenyl groups also led to the products in moderate yields (6 and 7). We were pleased to find that both acyclica nd cyclic unsaturated dialkylamides were well tolerated in this transformation (8)(9)(10)(11)(12)(13)(14)(15). Compared with the five-and six-membered heterocycles,the seven-membered heterocycle gave the highest yield (11,80%).…”

“…As the most successful surrogates for organotin compounds,t ris(trimethylsilyl)silane (TTMSS) has acted as as table,g reen, and commercially available organosilicon compound which has been widely employed as as ilyl source in free-radical chemistry. [10] As shown in Table 1, we began our investigation by screening reaction conditions for the dehydrogenative silylation using TTMSS [BDE(Si-H) = 82.3 kcal mol À1 ]a st he silicon radical precursor.T oo ur delight, the desired allylsilane product 1 (in ay ield of 40 %) was obtained at room temperature by irradiation with blue LEDs using Ir[dF(CF 3 )ppy] 2 (dtbbpy)PF 6 as the photocatalyst, quinuclidine (A)a st he HATc atalyst, Co(dmgH) 2 PyCl (II)asthe protonreduction catalyst, and N-methyl-N-phenylmethacrylamide as the silyl radical acceptor (entry 1). When 4CzIPN was used instead of Ir[dF(CF 3 )ppy] 2 (dtbbpy)PF 6 ,the yield of 1 was increased to 53 %( entry 2).…”