Anionic Domino Process for the One-Pot, Diastereoselective Synthesis of Dihydropyranols from β-Nitroalcohols
作者:Roberto Ballini、Luciano Barboni、Dennis Fiorini、Alessandro Palmieri
DOI:10.1055/s-2004-834820
日期:——
Bringing together β-nitroalkanols and cis-3-hexen-2,5-dione, in the presence of DBU as base and in acetonitrile as solvent, we achieved a one-pot diastereoselective synthesis of dihydropyranol derivatives. The nature of the latter compounds is consistent with the initial formation of a Michael adduct, followed by base-promoted elimination of nitrous acid leading to an allylic alcohol, which, finally, cyclises diastereoselectively to form a hemi-ketal functionality.
将β-硝基烷醇与顺-3-己烯-2,5-二酮在DBU作为碱和乙腈作为溶剂的条件下结合,我们实现了一锅法的非对映选择性合成二氢吡喃衍生物。这些化合物的性质与初步形成的迈克尔加成物一致,随后在碱的促进下消除亚硝酸,从而生成一个烯丙醇,最终选择性地环化形成半缩醛功能团。