Asymmetric synthesis of trans-4,5-disubstituted γ-butyrolactones involving a key allylboration step. First access to (-)-nicotlactone B and (-)-galbacin

S. Henrion (1) , Aurélie Macé (1) , M M Vallejos (2) , Thierry Roisnel (1) , B Carboni (1) , J M Villalgordo , F Carreaux (1)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 UNNE - Universidad Nacional del Nordeste [Corrientes]

An efficient asymmetric synthesis of trans-4,5-disubstituted γ-butyrolactones from aldehydes and enantioenriched γ-carbamate alkenylboronates is reported. The cornerstone of this strategy is the implementation of sequential [3,3]-allyl cyanate rearrangement/allylboration/nucleophilic addition/cyclisation reactions. Diverse γ-butyrolactones such as the flavouring compounds, (+)-trans-whiskey lactone and (+)-trans-cognac lactone, as well as an advanced intermediate towards the first synthesis of natural products, (-)-nicotlactone B and (-)-galbacin, have thus been obtained.

Domaines: Chimie organique

S. Henrion, Aurélie Macé, M M Vallejos, Thierry Roisnel, B Carboni, et al.. Asymmetric synthesis of trans-4,5-disubstituted γ-butyrolactones involving a key allylboration step. First access to (-)-nicotlactone B and (-)-galbacin. Organic & Biomolecular Chemistry, 2018, 16 (10), pp.1672-1678. ⟨10.1039/c8ob00101d⟩. ⟨hal-01744288⟩