Heteroatom-Guided Torquoselective Olefination of α-Oxy and α-Amino Ketones via Ynolates
作者:Mitsuru Shindo、Takashi Yoshikawa、Yasuaki Itou、Seiji Mori、Takeshi Nishii、Kozo Shishido
DOI:10.1002/chem.200500574
日期:2006.1
Ynolates were found to react with alpha-alkoxy-, alpha-siloxy-, and alpha-aryloxyketones at room temperature to afford tetrasubstituted olefins with high Z selectivity. Since the geometrical selectivity was determined in the ring opening of the beta-lactone enolate intermediates, the torquoselectivity was controlled by the ethereal oxygen atoms. From experimental and theoretical studies, the high Z
发现壬酸酯在室温下与α-烷氧基-,α-甲硅烷氧基-和α-芳氧基酮反应,得到具有高Z选择性的四取代的烯烃。由于几何选择性是在β-内酯烯醇中间体的开环中确定的,因此torquoselectivity由醚性氧原子控制。从实验和理论研究来看,高Z选择性是由轨道和空间相互作用而不是由螯合引起的。以类似的方式,α-二烷基氨基酮为烯烃提供了优异的Z选择性。这些产物可以容易地以良好的产率转化为多取代的丁烯内酯和γ-丁内酰胺。