4-Chlorophenyl ether was utilized as a new protecting group for the hydroxy function. This group was readily introduced to a sugar hydroxy group by using diaryliodonium triflate. Regioselective introduction of this protecting group at the vicinal cis -diol was achieved by using a copper catalyst and diaryliodonium triflate. This protecting group is stable under the Lewis acidic conditions of glycosylation, but it can be readily removed by the initial conversion into the corresponding 4-methoxyphenyl ether with use of a Pd catalyst, followed by oxidation with ammonium cerium (IV) nitrate [(NH 4 ) 2 Ce(NO 3 ) 6 ] (CAN).

中文翻译：

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介绍 4-氯苯基：羟基官能团的保护基团

4-氯苯基醚被用作羟基官能团的新保护基团。通过使用二芳基碘鎓三氟甲磺酸盐，可以很容易地将该基团引入糖羟基。通过使用铜催化剂和三氟甲磺酸二芳基碘鎓，在邻位顺式二醇处区域选择性地引入该保护基团。该保护基团在糖基化的路易斯酸性条件下是稳定的，但可以通过使用 Pd 催化剂初始转化为相应的 4-甲氧基苯基醚，然后用硝酸铈 (IV) 铵氧化 [(NH 4 ) 2 Ce(NO 3 ) 6 ] (CAN)。