1160747-79-4Relevant academic research and scientific papers
Synthesis of 2,5-diazabicyclo[2.2.2]octanes by dieckmann analogous cyclization
Holl, Ralph,Dykstra, Mareike,Schneiders, Martin,Froehlich, Roland,Kitamura, Masato,Wuerthwein, Ernst-Ulrich,Wuensch, Bernhard
experimental part, p. 914 - 919 (2009/04/11)
Starting with (S)-aspartate, methyl (S)-2-[1-allyl-4-(4-methoxybenzyl)-3,6- dioxopiperazin-2-yl]acetate 10 was synthesized in a four-step synthesis. Deprotonation of 10 and subsequent trapping of the first cyclization product led to the bicyclic mixed acetal 13 in 15% yield. The low yield of 13, compared with the yield of the corresponding glutamate derivatives, is explained by the higher energy (strain) of the bicyclo[2.2.2]octane system and the lower conformational flexibility of the shorter acetate side chain. The formation of a six-membered Na+-chelate 12 as intermediate is responsible for the high diastereoselectivity of the cyclization step.
