Protecting group and solvent control of stereo- and chemoselectivity in glucal 3-carbamate amidoglycosylation.
Protecting group and solvent control of stereo- and chemoselectivity in glucal 3-carbamate amidoglycosylation.
复制标题
葡萄糖3-氨基甲酸酯酰胺糖基化中立体选择性和化学选择性的保护基团和溶剂控制。
DOI：
10.1021/ol900126q
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发表时间：
2009
期刊：
影响因子：
5.2
通讯作者：
Rojas,ChristianM
中科院分区：
文献类型：
--
作者：
Gupta,Ritu;Sogi,KimberlyM;Bernard,SarahE;Decatur,JohnD;Rojas,ChristianM
在 Rh2(OAc)4 催化的葡萄糖 3-氨基甲酸酯的酰胺糖基化中，异头立体选择性和竞争性 C3−H 氧化的程度取决于 4O 和 6O 保护基团。无环保护允许高 α-端基异构体选择性，并在极性较小的溶剂中进一步改进，同时吸电子保护基团限制 C3 氧化副产物。烯烃插入和 C3−H 氧化之间的立体控制和分叉反映了构象、立体电子和诱导因素的相互作用。
In the Rh2(OAc)4-catalyzed amidoglycosylation of glucal 3-carbamates, anomeric stereoselectivity and the extent of competing C3−H oxidation depend on the 4Oand 6Oprotecting groups. Acyclic protection permits high α-anomer selectivity with further improvement in less polar solvents, while electron-withdrawing protecting groups limit C3-oxidized byproducts. Stereocontrol and bifurcation between alkene insertion and C3−H oxidation reflect an interplay of conformational, stereoelectronic, and inductive factors.