acid were reacted with hydrogen iodide in acetic acid to stereoselectively provide α-2-deoxy-2-hydrido analogs. The reaction proceeds through formation of an anomeric iodide which, in the presence of excess HI, is reduced to give an enol intermediate. Kinetic protonation of the intermediate enol gives a 3.4:1 α:β mixture of 2-deoxy-2-hydrido derivatives. Under thermodynamic conditions the α-anomer
使
N-乙酰神经氨酸的全乙酰化酯衍
生物与
碘化氢在
乙酸中反应,以立体选择性地提供α-2-脱氧-2-氢类似物。反应通过形成异头
碘化物而进行,其在过量HI的存在下被还原以得到烯醇中间体。中间体烯醇的动力学质子化得到了2-脱氧-2-氢衍
生物的3.4:1α:β混合物。在热力学条件下,仅形成α-异头物。