Hydrogen-Bond-Assisted Sequential Reaction of Silyl Glyoxylates: Stereoselective Synthesis of Silyl Enol Ethers
Chen Zhu1, Man-Yi Han1, Xiu-Xia Liang1
1Department of Chemistry, Key Laboratory of Green and Precise Synthetic Chemistry, Ministry of Education, Huaibei Normal University, Huaibei, Anhui 235000, P.R. China.
Abstract:
A novel hydrogen-bond-assisted sequential reaction of silyl glyoxylates is described. This method provides an efficient strategy for the synthesis of silyl enol ethers with high selectivity. In these transformations, hydrogen bonds from 2-nitroethanol and its derivatives are critical to the stereochemical outcome. Both E- and Z-isomers are achieved via Henry reaction/Brook rearrangement/elimination and Henry reaction/Brook rearrangement/retro-Henry reaction/elimination processes, respectively (up to 99:1 Z-selectivity, and 9.2:1 E-selectivity).
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