An efficient synthesis of N,N′-linked oligoureas

✍ Scribed by Mark E. Wilson; James S. Nowick

• Publisher: Elsevier Science
• Year: 1998
• Tongue: French
• Weight: 259 KB
• Volume: 39
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(98)01396-3

✦ Synopsis

This paper reports an efficient synthesis of N-alkyI-N,N'-Iinked oligoureas [-NR-CO-NH-CH2CH2-]n, which involves the repetition of three steps: (1) main-chain extension by ring-opening of N-(2-nitrobenzenesulfonyl)-2-imidazolidone (1) by a secondary amine RR'NH to afford sulfonamide RR'N-CO-NH-CH2CH2-NH-SO2Ar (2) side-chain attachment by N-alkylation of the sulfonamide with alkyl halide R"X, and (3) removal of the sulfonyl group to give a new secondary amine RR' N-CO-NH-CH2CH 2-NHR"). A tetraurea was prepared in 10 steps and 58% overall yield by this method.