Synthesis of Functionalized 1-Azaspirocyclic Cyclopentanones Using Bronsted Acid or <i>N-</i>Bromosuccinimide Promoted Ring Expansions
作者:Gregory R. Dake、Michaël D. B. Fenster、Paul B. Hurley、Brian O. Patrick
DOI:10.1021/jo0493572
日期:2004.8.1
onic acid or HCl) or N-bromosuccinimide, an electrophilicbromine source. Reactions promoted by N-bromosuccinimide tend to proceed in higher yields (80−95%) and with greater diastereoselectivity (3:1−1:0) compared to those reactions promoted by a Bronsted acid. In addition, N-bromosuccinimide promoted reactions can produce a complementary stereochemical outcome compared to the reactions using Bronsted