Palladium-Catalyzed Cross-Coupling of Silyl Electrophiles with Alkylzinc Halides: A Silyl-Negishi Reaction

Abstract

We report the first example of a silyl-Negishi reaction between secondary zinc organometallics and silicon electrophiles. This palladium-catalyzed process provides direct access to alkyl silanes. The delicate balance of steric and electronic parameters of the employed DrewPhos ligand is paramount to suppressing isomerization and promoting efficient and selective cross-coupling.

Nickel‐Catalyzed Selective Cross‐Coupling of Chlorosilanes with Organoaluminum Reagents

“…The representative strategies of CÀ Si bond formation [3][4][5][6][7][8][9][10][11] was classified in Scheme 1. Industrially, copper-catalyzed reactions of metal silicon with alkyl chlorides (i. e., the Müller-Rochow "direct process" method), [3] are performed to furnish a mixture of organochlorosilanes (RSiCl 3 , R 2 SiCl 2 , R 3 SiCl, etc.)…”

“…The introduction of phenyl group was also performed using triphenylaluminum to give 2'd in 68 % yield (Table 2, entry 5). Ethylphenyldichlorosilane (1 b) and diphenyldichlorosilane (1 c) were also tolerated and predominantly provided the corresponding monoalkylated products 2' in good yields ( Table 2, entries [6][7][8][9][10][11]. Considering the steric effect of the substituent in 1, we tested the reaction of methyl (p-tolyl)dichlorosilane (1 d) and methyl(o-tolyl)dichlorosilane (1 e).…”

Die selektive Arenhydrierung bietet einen direkten Zugang zu gesättigten Carbo‐ und Heterocyclen

“…B. [71] Unter Verwendung des Rhodium-CAAC-Präkatalysators 33 wurde eine allgemeine, cis-selektive Hydriermethode entwickelt (Abbildung 18 A). B.…”

Palladium-Catalyzed Cross-Coupling of Monochlorosilanes and Grignard Reagents

“…11 This “silyl-Negishi” strategy represents the natural polarity of the Si–C bond and takes advantage of the natural electrophilicity of silicon centers. While this reaction is highly complimentary to umpolung methods mentioned above and provides a useful strategy for preparing α-branched silanes, it was limited to the use of silyl iodide electrophiles.…”

“…11 Thus, we began this investigation by studying the use of other classes of alkyl nucleophiles. To this end, we investigated the reactivity of dimethylphenylsilyl chloride with isopropylmagnesium chloride using THF as solvent.…”