Nickel‐Catalyzed Reductive C(sp²)−Si Coupling of Chlorohydrosilanes via Si−Cl Cleavage

Abstract

We report here a new method for the synthesis of organohydrosilanes from phenols and ketones. This method is established through reductive CÀ Si coupling of chlorohydrosilanes via unconventional SiÀ Cl cleavage. The reaction offers access to aryl-and alkenylhydrosilanes with a scope that is complementary to those of the established methods. Electron-rich, electron-poor, and ortho-/meta-/para-substituted (hetero)aryl electrophiles, as well as cyclic and acyclic alkenyl electrophiles, were coupled successfully. Functionalities, including Grignard-sensitive groups (e.g., primary amine, amide, phenol, ketone, ester, and free indole), acid-sensitive groups (e.g., ketal and THP protection), alkyl-Cl, pyridine, furan, thiophene, Ar-Bpin, and Ar-SiMe 3 , were tolerated. Gram-scale reaction, incorporation of -Si(H)R 2 into complex biologically active molecules, and derivatization of formed organohydrosilanes are demonstrated.

Catalytic C(sp)–Si cross-coupling silylation of alkynyl bromides with hydrosilanes by palladium catalysis

“…To construct different silicon–carbon bonds via cross-coupling reactions, an attractive and alternative synthesis strategy based on transition metal catalysis has been established for Si–C bond-forming reactions (Scheme 1b). 3,4 In this context, hydrosilanes provide the most useful and essential reagents in the synthesis of structurally diverse organosilicon compounds through cross-coupling type silicon–hydrogen (Si–H) bond functionalization, 5 owing to their unique chemical and physical properties. 6 However, the transition metal-catalyzed C(sp)–Si bond-forming reaction with hydrosilanes to obtain alkynylsilane derivatives is less explored in homogeneous catalysis but it occurs smoothly in the presence of strong bases 7 or heterogeneous gold catalysts.…”

“Thiol-free synthesized” and sustainable thiolating synthons for nickel-catalyzed reductive assembly of sulfides with high efficiency

“…Based on the significant achievements in the reductive cross-coupling for assembling C–C/C–X (X = Si, Ge, S, Se) bonds 10 with our continuing interest 11 in the development of efficient reagents in synthetic chemistry, we speculate that N -thiophthalimides can serve as ideal precursors due to the weak “N–S” bond and easy modification of the reactivity by replacement of substituents on the reagent's skeleton (Scheme 1c). N -Thiophthalimides are also air and moisture stable solids and can be further subjected to cross-electrophilic coupling.…”

Bis(pinacolato)diboron-Enabled Ni-Catalyzed Reductive Coupling of Alkyl with Aryl/Vinyl Electrophiles

“…3 Recent advances have also been capitalized on accommodating alkyl-NHPI esters, -Katritzky salts, -ammonium salts and -oxalates as the alkyl coupling partners, permitting effective transformation of the C-C, C-N and C-O bonds into value-added C(sp 3 )-C and C(sp 3 )-heteroatom bonds. [5][6][7][8][9] In a sharp contrast, meagre efforts have been devoted to the development of non-metallic reductants that outcompete Zn and Mn. Towards this end, Weix has advanced tetra(dimethylamino)ethylene (TDAE) as an organic reductant that displayed moderate efficiencies in the Ni-catalyzed arylation of alkyl halides with aryl halides.…”