38425-50-2Relevant academic research and scientific papers
Cycloadditions, 6 Intramolecular Diels-Alder Reaction of Allenecarboxanilides; Variation of the Residue Geminal to the Carboxamide Group
Henn, Lothar,Himbert, Gerhard,Diehl, Klaus,Kaftory, Menahem
, p. 1953 - 1963 (2007/10/02)
The 2,3-butadienanilides 6a-h, unsubstituted in the ω-position, are synthesized by the ynamine way and submitted to thermolysis.They isomerize without exception by intramolecular Diels-Alder reaction more or less quickly, irreversibly, and quantitatively
(Aminoethinyl)metallierungen, VIII. Umsetzungen von β-silylierten Inaminen mit Keten; Konkurrenz von (Aminoethinyl)silylierung und -Cycloaddition
Henn, Lothar,Himbert, Gerhard
, p. 1015 - 1026 (2007/10/02)
(Silylethynyl)amines 1 react with ketene (2) to yield according to the principle of the -cycloaddition preferentially the 2-silyl-2,3-butadienamides 6 and the 3-amino-2-silyl-2-cyclobuten-1-ones 7.The latter ones hydrolyze easily to the corresponding silyl-free cyclobutenones 8.In some cases one can isolate besides these compounds (see the reactions of 1a and 1e) or exclusively (see the reaction of 1d) 1:2- and 1:3-adducts, the formation of which can be explained via the non detectable (3-siloxy-3-buten-1-ynyl)amines 4 .These enyn-amines add to their C/C triple bond a second molecule of ketene (2) to give the allene carboxamides (see 5d) and cyclobutenones 9.The compounds 9 easily hydrolyze to the corresponding acetylcyclobutenones 10 and they react with exceeding ketene (2) to form the 1:3-adducts 11.The cyclobutenone 9d isolable in substance adds diphenyl ketene and tert-butylcyanoketene in the same way to give the analogous chain prolongation products 14 and 15.
