4-[(2-四氢吡喃)氧]苯酚的合成

Synthesis of 4-[(Tetrahydro-2H-pyran-2-yl)oxy] phenol

4-[(2-四氢吡喃)氧]苯酚(脱氧熊果苷)是一种有效的酪氨酸酶抑制剂,可作为化妆品添加剂来实现美白功能。今以对苯二酚为原料,经过对苯二酚单苄醚化、另一酚羟基四氢吡喃醚化、加氢脱苄基等步骤合成4-[(2-四氢吡喃)氧]苯酚。该路线中二氢吡喃保护羟基采用了吡啶对甲苯磺酸盐(PPTS)作催化剂,获得了满意的结果。各步反应比较适宜的工艺条件(反应温度,反应时间,摩尔收率)分别为,对苯二酚单苄醚化:75℃,3h,36%;另一酚羟基四氢吡喃醚化:30℃,5h,80%;加氢:30℃,24h,79%。产物熔点与文献报道相符,并通过1H-NMR确认了脱氧熊果苷的结构。

4-[（Tetrahydro-2U-pyran-2-yl）oxy]phenol is an effective tyrosinase inhibitor, which could be used as cosmetic additive to achieve lightening skin. A synthetic rout of 4-[（Tetrahydro-2U-pyran-2-yl）oxy]phenol was designed by using hydroquinone as raw material and via hydroquinone monobenzyl etherification, another phenolic hydroxyl tetrahydropyran etherification and debenzylation by catalytic hydrogenation. Comparing with methods reported in literatures, the second step can get a good result with PPTS as catalyst. The suitable reaction conditions （temperature, time and molar yield） of the proposed rout were found as follows： 75℃, 3 h and 36% for hydroquinone monobenzyl etherification; 30℃, 5 h and 80% for another phenolic hydroxyl tetrahydropyran etherification; 30℃, 24 h and 79% for hydrotreating debenzylimine. The melting point of the obtained product was found to be in conformity with those reported in literatures, and the structure of the title compound was confirmed by 1H-NMR.