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Simple modifications of our novel ligand (Xing-Phos) were presented in this work, and a series of aromatic tertiary amide derived non-biaryl atropisomers were successfully synthesized in good yields. In addition, it was found that the multifunctional aromatic tertiary amide derived non-biaryl atropisomers exhibited an excellent endo -selectivity in the silver-catalyzed [3+2]-cycloaddition of azomethine ylides with N -aromatic maleimide. And especially, good to high levels of enantioselectivity (up to 98% ee ) was obtained with a wide range of substrates in the presence of syn -( R , R S )- 2a (Xing-Phos). Furthermore, on the basis of the experimental data, it was demonstrated that a trace amount of water play an important role in the enhancement of enantioselectivity. [ABSTRACT FROM AUTHOR]

Abstract: We report here the first example of the reduction of acylsilanes to α-hydroxysilanes, in which diethylzinc was used as a highly reactive agent in the presence of Ti(OiPr)4 or other Lewis acids. The reduction typically proceeds to give synthetically useful α-hydroxysilanes in good yields. [Copyright &y& Elsevier]