Application of Odorless Thiols for the Cleavage of 2‐ and 4‐Nitrobenzenesulfonamides
摘要:
Several odorless or faint-smelling thiols were tested to cleave 2- and 4-nitrobenzenesulfonyl groups, which are widely utilized for selective protection and activation of amines. p-Mercaptobenzoic acid (7) was found to be the most useful thiol for cleaving the o- and p-nosyl groups in terms of ease of separation of the product from the workup residue, reaction temperature, and reaction time.
2- and 4-Nitrobenzenesulfonamides: Exceptionally versatile means for preparation of secondary amines and protection of amines
作者:Tohru Fukuyama、Chung-Kuang Jow、Mui Cheung
DOI:10.1016/0040-4039(95)01316-a
日期:1995.9
4-Nitrobenzenesulfonamides, readily prepared from primary amines, undergo smooth alkylation by Mitsunobu reaction or by conventional methods to give N-alkylated sulfonamides in near quantitative yields. These sulfonamides could be deprotected readily via Meisenheimer complexes upon treatment with thiolates in DMF at room temperature, giving secondaryamines in high yields.