Thieme Chemistry Journal Awardees- Where are They Now? An Asymmetric Organocatalytic Sequence towards 4a-Methyl Tetrahydroxanthones: Formal Synthesis of 4-Dehydroxydiversonol
Tricyclic systems generated by an asymmetric vinylogous aldol-oxa-Michael reaction of salicylaldehydes with senecialdehyde were further elaborated using a strategy developed by Tietze et al. to generate 4a-methyl tetrahydroxanthones.
The base-catalyzedcondensation of α,β-unsaturated carbonyl compounds with 2-hydroxybenzaldehydes yielding tetrahydroxanthones and dihydrobenzopyrans has been investigated. A novel access to highly functionalized dihydrobenzopyrans via a mild generation of the dienol of senecialdehyde and subsequent conjugated aldol reaction has been reported.