Diastereoselective Intermolecular Addition of the 1,3-Dioxolanyl Radical to <i>N</i>-Acyl Aldohydrazones. Asymmetric Synthesis of α-Amino Acid Derivatives
作者:Marta Fernández、Ricardo Alonso
DOI:10.1021/ol034696n
日期:2003.7.1
and furyl) efficiently trap the 1,3-dioxolanyl radical intermolecularly without external activation at temperatures as low as -78 degrees C. For alkyl aldohydrazones, good diastereoselectivities are obtained in the presence of InCl(3) at low temperature. Elaboration of the adducts (II) allows for the asymmetric synthesis of alpha-amino acid derivatives.
[反应:请参阅文本] N-酰基羟乙基叠氮I(R = CO(2)Et,烷基,芳基和呋喃基)在低至-78摄氏度的温度下有效地分子间捕获1,3-二氧戊环基,而无外部活化。对于烷基铝hydr,在低温下在InCl(3)存在下可获得良好的非对映选择性。加合物(II)的精制允许α-氨基酸衍生物的不对称合成。