A process for preparing a 5-halophenol, ortho-substituted by an electron-donating group, is described. Also described, is a process for preparing a sulphonic ester of an ortho-substituted phenol, which is the synthesis intermediate for the ortho-substituted 5-halophenol. The process for preparing a phenol ortho-substituted by an electron-donating group and protected in the form of a sulphonic ester can include reacting a phenol ortho-substituted by an electron-donating group with a sulphonylating agent in the presence of a Lewis acid. The process for preparing a 5-halophenol ortho-substituted by an electron-donating group can include a first step of preparing a phenol ortho-substituted by an electron-donating group and protected in the form of a sulphonic ester, as described above; a second step of halogenating the protected phenol intermediate obtained in the preceding step, in the position para to the electron-donating group; and a third step of deprotecting the sulphonic ester function to hydroxyl.
描述了一种制备5-卤
酚的过程,其邻位取代为电子给予基团。还描述了一种制备邻位取代
酚的
磺酸酯的过程,该
酚是邻位取代的5-卤
酚的合成中间体。制备邻位取代
酚的过程,该
酚的邻位取代为电子给予基团,并以
磺酸酯的形式保护,可以包括在Lewis酸的存在下,将邻位取代为电子给予基团的
酚与磺化试剂反应。制备邻位取代为电子给予基团的5-卤
酚的过程可以包括以下步骤:首先,制备如上所述的邻位取代为电子给予基团并以
磺酸酯形式保护的
酚;其次,在前述步骤中获得的保护
酚中间体中,在电子给予基团对位进行卤代反应;最后,去除
磺酸酯功能以得到羟基。