Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Org Lett. 2013 Aug 16;15(16):4130-3. doi: 10.1021/ol401810b. Epub 2013 Jul 31.
A copper(I)-catalyzed anomeric aminoalkynylation reaction of unprotected aldoses was realized. Use of an electron-deficient phosphine ligand, boric acid to stabilize the iminium intermediate, and a protic additive (IPA) to presumably enhance reversible carbohydrate-boron complexation were all essential for efficient conversion. The reaction proceeded well even with a natural disaccharide substrate, suggesting that the developed catalytic reaction could be useful for the synthesis of glycoconjugates with minimum use of protecting groups.
实现了无保护醛糖的铜（I）催化端基氨基炔基化反应。使用缺电子膦配体、硼酸稳定亚胺中间体，以及质子添加剂（IPA）来增强可逆的碳水化合物-硼络合，这些都是有效转化所必需的。即使使用天然二糖底物，反应也能顺利进行，这表明开发的催化反应可用于最小化使用保护基的糖缀合物的合成。
