A synthesis of optically active α-quaternary α-amino acids and esters by assembling three components, ketones, (R)-chloromethyl p-tolyl sulfoxide, and sodium azide, via sulfinyloxiranes
作者:Tsuyoshi Satoh、Mizue Hirano、Akio Kuroiwa、Youhei Kaneko
DOI:10.1016/j.tet.2006.06.112
日期:2006.9
yields. The oxidation of the azido aldehydes with iodine in methanol in the presence of KOH followed by the catalytic hydrogenation resulted in α-quaternary α-amino acid methyl esters in good yields. When these reactions were carried out starting from unsymmetrical ketones and optically pure (R)-chloromethyl p-tolyl sulfoxide, a new method for a synthesis of optically active α-quaternary α-amino acids
在低温下用酮处理氯甲基对甲苯基亚砜的α-亚磺酰基锂的碳负离子,以几乎定量的产率得到加合物,将其暴露于t- BuOK以高产率得到亚磺酰基环氧乙烷。使亚磺酰基环氧乙烷与苄胺反应,得到α-氨基醛,将其在甲醇中用碘氧化,以中等收率得到α-氨基羧酸酯。用叠氮化钠处理亚磺酰基环氧乙烷,以高收率得到α-叠氮基醛。用NaClO 2氧化然后催化氢化α-叠氮基醛的叠氮基,以良好的总收率得到α-季α-氨基酸。在KOH存在下,在甲醇中用碘将叠氮基醛与碘氧化,然后进行催化加氢,从而以高收率得到α-季铵α-氨基酸甲基酯。当这些反应从不对称酮和光学纯的(R)-氯甲基对甲苯基亚砜开始进行时,实现了以良好的总收率合成光学活性的α-季α-氨基酸和酯的新方法。