157464-27-2Relevant articles and documents
N,N-Bis(trimethylsilyl)ynamines: Cycloaddition Reactions with Dimethyl Acetylenedicarboxylate and Ketenes
Schulte, Norbert,Moeller, Manfred H.,Rodewald, U.,Wuerthwein, Ernst Ulrich
, p. 1287 - 1294 (2007/10/02)
N,N-Bis(trimethylsilyl)ynamines 1 react with dimethyl acetylenedicarboxylate (2) in a molar ratio of 1:2 to afford 3-cyclopropenylfurans 3.Configuration and conformation of 3a are confirmed by X-ray crystallography.Addition of a further mol of 1 furnishes the fumarates 4.With ketenes 5 (5c, d are prepared in situ) a competition between the formation of cyclic butenone derivatives 6 and allenic imidates 7 is observed, depending on the substitution pattern of 1.After hydrolytic workup, the corresponding amides 10 or the vinylogous amides 9 are obtained in good yield.These experiments indicate that the silylated ynamines 1 show a completely different, more selective reactivity towards dimethyl acetylenedicarboxylate compared to N,N-dialkyl-substituted ynamines, yielding furan derivatives instead of anilines.Towards ketenes, however, a similar cycloaddition reactivity as for N,N-dialkynylamines is observed. - Key Words: Ynamines, N,N-bis(trimethylsilyl)- / Cycloaddition reactions / Cyclopropenes / Furans / Ketenes / Cyclobutenones / Allenylcarboxamides
