Beilstein J. Org. Chem.2022,18, 1642–1648, doi:10.3762/bjoc.18.176
described to give β-hydroxylactones with high diastereoselectivities. The stereoselectivity of this cyclization is highly solvent dependent and can give syn- or anti-β-hydroxylactones with high diastereoselectivity. This methodology was also applied to the synthesis of a chiral necicacidlactone which is a
structural component of the pyrrolizidine alkaloid monocrotaline.
Keywords: β-hydroxylactone; intramolecular reductive aldol cyclization; necicacidlactone; rhodium catalyst; Introduction
Carbon–carbon bond-forming reactions are among the most important reactions in the synthetic chemistry toolbox and the
formation systems, we herein report a rhodium-catalyzed intramolecular reductive aldol-type cyclization and its application for the synthesis of a chiral necicacidlactone.
Results and Discussion
Rh-catalyzed intramolecular cyclization
When applying our previously reported conditions [43], the