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The transition-metal-catalyzed synthesis of chiral silacycles is a challenging processes in organosilicon chemistry. Herein, we report a facile and regioselective synthesis of a novel class of 2,3-dihydrosilole derivatives with good yields via the palladium-catalyzed Heck-type reaction of silacyclopentenes (SCPs) with aryl iodides. Preliminary investigations on the enantioselective version of this palladium-catalyzed Heck-type process reveal that the presence of N -Boc- l -proline allows the diastereo- and enantioselective formation of chiral 2,3-dihydrosilole derivatives bearing both carbon and silicon-stereogenic centers. [ABSTRACT FROM AUTHOR]

Organosilicon compounds are important reagents and synthetic intermediates that play a key role in the construction of new materials and complex products. Here we show a highly diastereoselective rhodium‐catalyzed cycloisomerization of 1,6‐dienes, in which the use of (EtO)3SiH accelerates the intramolecular cyclization reaction to afford a novel spiro‐fused succinimide and pyrazolone derivatives in moderate to excellent yields as a single diastereoisomer. The proposed mechanism involves an active Rh−H species from the hydrosilane that is the H‐donor in this spiro‐type cycloisomerization reaction. [ABSTRACT FROM AUTHOR]

Given the powerful potential of chiral-at-silicon chemistry, enantioselective synthesis of Si-stereogenic centers has attracted substantial research interest in recent years. However, the catalytic asymmetric synthesis of Si-stereogenic organosilicon compounds remains an appealing venture and is a challenging subject because of the difficulty in achieving high reactivity and stereoselectivity for "silicon-center" transformations. Herein, we disclose a highly enantioselective palladium-catalyzed hydrosilylation of 1,3-diynes with dihydrosilanes, which enables the facile preparation of Si-stereogenic enynes and an enyne-linked chiral polymer (polyenyne) in good yields and excellent ees (up to >99%) by desymmetrization. The unusual stereoselectivity in this reaction is achieved by precisely controlling the steric hindrance and electronic effect of the newly developed chiral ligands, resulting in a wide range of chiral silanes and a Si-containing polymer bearing a Si-stereogenic center which is otherwise difficult to access. The key to the high enantioselectivity relies on catalyst aggregation-induced non-covalent interaction, which exerts a remarkably positive influence on the Si-H bond activation and enhancement of enantioselectivity, in which the palladium/P-ligand complex was proved to be air-stable and moisture-insensitive in this reaction., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

Organosilicon compounds are important reagents and synthetic intermediates that play a key role in the construction of new materials and complex products. Here we show a highly diastereoselective rhodium-catalyzed cycloisomerization of 1,6-dienes, in which the use of (EtO) 3 SiH accelerates the intramolecular cyclization reaction to afford a novel spiro-fused succinimide and pyrazolone derivatives in moderate to excellent yields as a single diastereoisomer. The proposed mechanism involves an active Rh-H species from the hydrosilane that is the H-donor in this spiro-type cycloisomerization reaction., (© 2021 Wiley-VCH GmbH.)