作者:Jeffrey J. Posakony、Timothy J. Tewson
DOI:10.1055/s-2002-25766
日期:——
N-benzyl [1,2,3]-oxathiazolidine 2,2-dioxides (cyclic sulfamidates) were synthesized from their corresponding β-amino alcohols and used as substrates in fluorination reactions with tetrabutylammonium fluoride (TBAF). After desulfonation of the intermediates, the N-benzyl fluoroamines were debenzylated by transfer hydrogenolysis with Pd/C to yield (S) and (R)-2-amino-1-fluoropropanes (2b and 3b, respectively, both with 95% ee). The reactions were carried out on multi-gram scale without the need for chromatographic purification of the intermediates. In the presence of carbonate, the (S)- and (R)-N-benzylfluoroamines underwent intramolecular cyclizations in which fluoride was displaced to yield cyclic carbamates 13 and 14.
N-苄基[1,2,3]-噻唑烷-2,2-二氧化物(循环磺酰胺酸酯)是由相应的β-氨基醇合成的,并用作与四丁基氟化铵(TBAF)进行氟化反应的底物。在中间体去磺化后,通过与Pd/C的转移氢解反应去除苄基,生成(S)和(R)-2-氨基-1-氟丙烷(分别为2b和3b,两者的ee均为95%)。这些反应是在多克级规模上进行的,无需对中间体进行色谱纯化。在碳酸盐存在的情况下,(S)-和(R)-N-苄基氟胺发生分子内环化反应,氟离子被取代,生成循环碳酸酯13和14。