一种酰胺转化为氨基的方法PreparationofMethylNSubstituted.pdfVIP

Synthetic Communicationsw, 35: 2091–2098, 2005 Copyright #Taylor Francis, Inc. ISSN 0039-7911 print/1532-2432 online DOI: 10.1081/SCC-200066695 Preparation of Methyl N-Substituted Carbamates from Amides through N-Chloroamides Gene A. Hiegel and Tyrone J. Hogenauer Department of Chemistry and Biochemistry, California State University, Fullerton, California, USA Abstract: Amides are chlorinated on the nitrogen using trichloroisocyanuric acid, and the N-chloroamides are then rearranged to the corresponding methyl N-substituted car- bamates by sodium methoxide in methanol. Keywords: Amides, N-chloroamides, methyl N-substituted carbamates, preparation, rearrangement, synthesis, trichloroisocyanuric acid N-Chloramides are easily prepared from amides using trichloroisocyanuric acid [TCICA; 1,3,5-trichloro-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione; C Cl N O ], 3 3 3 3 a stable solid.[1] Treatment of N-chloroamides with aqueous hydroxide gives amines with one less carbon in a reaction known as the Hofmann degradation.[2] An intermediate in this reaction is the isocyanate, and that reacts with hydroxide followed by decarboxylation to give the corresponding amine (Scheme 1). We report that treatment of N-chloroamides with sodium methoxide in methanol gives the corresponding methyl N-substituted carbamates (Scheme 2). Although similar reactions have been reported using N-bromoamides,[3] a search of the chemical literature did not turn up previous examples using N-chloroamides. The results are summarized in Table 1. Carbamates can be hydrolyzed to the corresponding amines, reduced to N-methylamines with lithium aluminum hydride,