Synthesis of Allylsilanes via Nickel-Catalyzed Cross-Coupling of Silicon Nucleophiles with Allyl Alcohols

Abstract

NiCl 2 (PMe 3 ) 2 -catalyzed reaction of allyl alcohols with silylzinc reagents, including PhMe 2 SiZnCl, Ph 2 MeSiZnCl, and Ph 3 SiZnCl, was performed, achieving allylsilanes in high yields. Aryl-and heteroaryl-substituted allyl alcohols, (E)-3-arylprop-2-en-1-ols, 1-aryl-prop-2-en-1-ols, and (E)-1-phenylpent-1-en-3-ol can be employed in the transformation. A range of functional groups as well as heteroaryl groups were tolerated. Reaction exhibited high regioselectivity and E/Z-selectivity when 1-or 3-aryl-substituted allyl alcohols were used as the substrates. Reaction of chiral allyl alcohol, (S,E)-1-phenylpent-1-en-3-ol, yielded a configuration-inversion product (R,E)-dimethyl(phenyl)(1-phenylpent-1-en-3-yl)silane.

Nickel‐Catalyzed Allylic Substitution Reactions: An Evolving Alternative

“…used a NiCl 2 (PMe 3 ) 2 precatalyst that can be reduced by the respective silicon-nucleophile (PhMe 2 SiZnCl) while the activation of the allyl alcohol was accomplished by MeZnCl. [76] Remarkably, complete inversion of configuration was observed for an enantioenriched substrate, hinting at a putative enyl intermediate. However, σ-π-σ isomerization was found to be faster and complete transfer of the regioselectivity was not always observed.…”

Regioselective Silylations of Propargyl and Allyl Pivalates through Ca-Promoted Reductive C(sp3)–O Bond Cleavage

“…Allyl pivalate 6 underwent reductive silylation to afford allylsilane 7a ( E isomer) in 58% yield. Notably, the reaction of allyl pivalate 8a gave the same product as pivalate 6 , which indicates that pivalate 8a undergoes allylic rearrangement . Similarly, pivalate 9 reacted to afford allylsilane 10 in 68% yield.…”

“…In addition to this pioneering work, in 2021, Rasappan et al reported the construction of a series of benzylsilanes and allylsilanes through C­(sp 3 )–OMe cleavage catalyzed by nickel (Scheme b). While silylations of alcohols and their derivatives using nucleophilic silicon reagents are well-documented, the development of simple silylation strategies using more common electrophilic silylating agents through C­(sp 3 )–O bond cleavage remains challenging.…”

Copper-Catalyzed Reaction of 2,3-Allenols with Silylzinc Reagents: Access to 2-Silyl-1,3-butadienes

“…However, this method still suffers from several drawbacks: (1) a mixture of E / Z isomers was formed if secondary allenols were used as the cross-coupling partners, especially poor stereoselectivity when 1-alkyl-2,3-allenols were submitted to the reaction; (2) noble metal palladium was used as the catalyst; and (3) 2-(methyldiphenylsilyl)-1,3-dienes cannot be synthesized and 2-(dimethylphenylsilyl)-1,3-dienes were formed with expensive 1,1,2,2-tetramethyl-1,2-diphenyldisilane as the silicon source. On the basis of the pioneering studies by Fu and co-workers on the nickel-catalyzed silylation of electrophiles with silylzinc reagents, our group synthesized allylsilanes via the cross-coupling of allyl alcohols with silylzinc chlorides . We anticipated that 2-silyl-1,3-butadienes could be efficiently prepared by reaction of 2,3-allenols with silylzinc reagents under cheap metal catalysis, accompanied by high stereoselectivity.…”