The phosphine oxide-catalyzed asymmetric intramolecular aldol reactions of diketones were investigated. The combination of tetrachlorosilane and a chiral phosphine oxide catalyst promoted the acetyl-selective enolization of diketones, and the subsequent intramolecular aldol reaction occurred in an enantioselective manner. The introduction of two trimethylsilyl groups at the 4- and 4'-positions in BINAP dioxide catalyst improved the enantioselectivity. This reaction provides an effective synthetic method to access β-tertiary-hydroxy cyclohexanones in high yields and with high enantioselectivity.

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Trichlorosilyl triflate-promoted directed cross-aldol reaction between ketones in the presence of a chiral phosphine oxide as an organocatalyst is described. This is the first enantioselective cross-aldol reaction between simple ketones with good enantioselectivity.

A Pd/Cu catalyst-controlled regiodivergent and stereospecific ring-opening C(sp3)–Si cross-coupling of 2-arylaziridines with silylborane has been developed and a new tandem reaction to give another regioisomer of silylamine has been discovered.

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