A p-methoxybenzyl (PMB) protection/deprotection approach toward the synthesis of 5-phenoxy-4-chloro-N-(aryl/alkyl) thiophene-2-sulfonamides

作者：Williams Alfred L^*; Dandepally Srinivasa R; Kotturi Sharadsrikar V

来源：Molecular Diversity, 2010, 14(4): 697-707.

DOI：10.1007/s11030-009-9208-y

• Nucleophilic aromatic substitution
• 4,5-Dichlorothiophene-2-sulfonyl chloride
• p-Methoxybenzyl (PMB) group
• 5-Phenoxy-4-chloro-N-(aryl/alkyl)thiophene-2-sulfonamides

The synthesis of 17 phenoxy substituted 4-chloro-N-(aryl/alkyl)thiophene-2-sulfonamides using a PMB protection/deprotection strategy is described. Nucleophilic displacement of p-methoxybenzyl (PMB) protected 4,5-dichloro-N-(aryl/alkyl)-thiophene-2-sulfonamides was carried out with different phenols under mild basic conditions. Reaction times of 3-6 h and overall yields of 78-98% were achieved with the PMB group in place compared to no reaction without this protecting group. The PMB group was easily and selectively removed in 68-98% yield using TFA in DCM.

• 出版日期2010-11