1360067-20-4Relevant academic research and scientific papers
Promotion of asymmetric aza-claisen rearrangement of N-allylic carboxamides using excess base
Yoshizuka, Makoto,Nishii, Takeshi,Sasaki, Hiromi,Kitakado, Junko,Ishigaki, Noriko,Okugawa, Shinobu,Kaku, Hiroto,Horikawa, Mitsuyo,Inai, Makoto,Tsunoda, Tetsuto
experimental part, p. 2967 - 2970 (2012/01/05)
The aza-Claisen rearrangement of the enolate of N-(Z)-crotyl-N-(S)- phenethylpropanamide did not proceed in the presence of 1.5 equivalents of LHMDS as a base. However, the use of a large excess of base (10 equiv) promoted the reaction to give N-(S)-phenethyl-anti-2,3-dimethylpent-4-enamide with good stereoselectivities (anti/syn = ca. 95:5). An excess of base stabilized the amide enolates and prevented the decomposition to the ketene to prompt the rearrangement of various carboxamides with good stereoselectivity. This reaction provided a new method for the construction of asymmetric quaternary carbon centers. Georg Thieme Verlag Stuttgart · New York.
