Cu(II)-Catalyzed Allylic Silylation of Morita–Baylis–Hillman Alcohols via Dual Activation of Si–B Bond and Hydroxyl Group

Abstract

The reaction of Morita-Baylis-Hillman (MBH) alcohols with Me2PhSiBpin under the catalysis of Cu(OTf)2/pyridine in methanol has been developed. The direct silylation of allylic alcohols via dual activation of the Si-B bond and the hydroxyl group of the MBH alcohol provides an efficient and convenient method for the synthesis of functionalized allylsilanes.

Copper‐Catalyzed One‐Pot Borylative Aldolisation β‐Fluoride Elimination for the Formal Addition of Acrylates to Carbonyl Moieties

“…Having synthesized products 8 , we started to study their potential as starting material for further transformation in useful compounds. Therefore, we devised a reaction to obtain diene 10 b by an acetate elimination and applied a previously reported silylation/elimination procedure to obtain the tetrasubstituted allylsilane 11 b in high yield and selectivity (Scheme ) …”

“…Therefore, we devisedareaction to obtain diene 10 b by an acetate elimination and applied ap reviously reported silylation/elimination procedure to obtain the tetrasubstituted allylsilane 11 b in high yield and selectivity (Scheme 5). [21] In conclusion, we have developed ah ighly efficient and broadly applicable alternative route to the classical MBH reaction. We describe this new approach asaone-pot domino borylation/aldolisation elimination process.…”

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

“…A range of methods for synthesis of allylsilanes have been developed. Among them, silylation of allylic substrates with silicon nucleophilic reagents such as silylzinc, silylmagnesium, silyltin, and silylboron reagents, as well as disilanes, , under palladium or copper catalysis, has attracted great attention. The allylic substrates were mainly allyl halides and allyl alcohol derivatives such as allylic ethers, allylic carboxylates, allylic carbonates, and allylic phosphates.…”

“…In the absence of a transition-metal catalyst, the cross-coupling cannot occur in tetrahydrofuran (THF) at 80 °C (Table , entry 1). According to the reports in the literature, copper or palladium can catalyze the cross-coupling of allyl alcohol derivatives with silicon-based nucleophiles. − However, the reaction of 1a with 2a did not occur in the presence of CuI or [Pd­(π-allyl)­Cl] 2 (see Table , entries 2 and 3). This probably results from a difficult oxidation addition process of copper or palladium with a metal salt of allylic alcohol, whereas nickel can catalyze the reactions of alkoxide salts or phenoxide salts via the C–O bond cleavage. , Hence, nickel catalysts were tested next.…”

Synthesis of multi-substituted vinylsilanes via copper(i)-catalyzed hydrosilylation reactions of allenes and propiolate derivatives with silylboronates

“…Firstly, the Et 3 N could help to activate the B-Si bond via possible coordination between nitrogen and boron atoms. 23 In the presence of a copper catalyst, species A could be generated. Due to the electron density bias of allenes with an electron-withdrawing group, an addition of Si-Cu into the double bond will afford an allylic copper species B which could then undergo protonolysis in the presence of t BuOH to give the desired product 3.…”