Studies on the Lewis acid mediated cleavage of α-aminoacetals: synthesis of novel 1,2-aminoethers, and evidence for α-alkoxy aziridinium ion intermediatesElectronic supplementary information (ESI) available: correlation of 1H NMR spectra between the syn and anti diastereomeric series. See http://www.rsc.org/suppdata/ob/b2/b210116e/
作者:Mark A. Graham、Alan H. Wadsworth、Abdul Zahid、Christopher M. Rayner
DOI:10.1039/b210116e
日期:2003.2.27
reactive intermediates involved in the reaction. With diethylzinc, it is most likely that the reaction proceeds by coordination of the nucleophile to the amino group followed by transfer of an ethyl group to an alpha-oxocarbenium ion. With non-coordinating nucleophiles, the stereochemical outcome can be rationalised in terms of addition to the possible alpha-alkoxy aziridinium ion intermediates.
TMSOTf诱导的α-氨基缩醛的亲核裂解可用于制备各种取代的1,2-氨基醚。特别地,有机金属试剂,N-杂环和烯胺全部有效地反应以高收率得到产物。在适当的情况下,可以实现良好的立体控制水平,但这在很大程度上取决于亲核试剂和底物的性质,二乙基锌在一系列底物上被证明特别有效。立体控制的程度可用于推断反应中涉及的反应性中间体的性质。对于二乙基锌,最有可能通过亲核体与氨基的配位,然后将乙基转移至α-氧碳鎓离子来进行反应。对于非配位亲核试剂,