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The asymmetric cyanation of acylsilanes affords densely functionalized tetrasubstituted chiral carbon centers bearing silyl, cyano, and hydroxy groups, which are of particular interest in synthetic and medicinal chemistry. However, this method has been limited to a few enzymatic approaches, which employ only one substrate because of substrate specificity. Here we show the non-enzymatic catalytic asymmetric cyanation of acylsilanes using a chiral Lewis base as an enantioselective catalyst, trimethylsilyl cyanide as a cyanating reagent, and isopropyl alcohol as an additive to drive catalyst turnover. High enantio- and site-selectivities are achieved in a catalytic manner, and a variety of functional groups are installed in optically active acylsilane cyanohydrins, thus overcoming the limitations imposed by substrate specificity in conventional enzymatic methods. A handle for the synthetic application of the products is also established through the development of a catalyst for protecting acylsilane cyanohydrins, which are unstable and difficult to protect alcohols. Catalytic asymmetric cyanation of ketones is a straightforward method to construct tetrasubstituted chiral carbon centers, but for acylsilanes this method has been limited to enzymatic approaches. Here, non-enzymatic catalytic asymmetric cyanation of acylsilanes is accomplished using a chiral Lewis base as an enantioselective catalyst. [ABSTRACT FROM AUTHOR]

The strained olefins in trans‐cyclooctenes serve as efficient catalysts for halolactonizations, including bromolactonizations and iodolactonizations. The trans‐cyclooctene framework is essential for excellent catalytic performance, and the substituents also play important roles in determining efficiency. These results are the first demonstration of catalysis by a trans‐cyclooctene. The strained olefins in trans‐cyclooctenes serve as efficient catalysts for halolactonizations, including bromolactonizations and iodolactonizations. The trans‐cyclooctene framework is essential for excellent catalytic performance, and the substituents also play important roles in determining efficiency. [ABSTRACT FROM AUTHOR]