Chemoenzymatic synthesis of enantiopure α-substituted cyclohexanones from aromatic compounds

Chemoenzymatic Synthesis of trans-Tetrahydrofuran Cores of Annonaceous Acetogenins from Bromobenzene

“…The sequence for both THF cores started with the toluene dioxygenase-mediated oxidation of bromobenzene to produce enantiopure cis -diol 1 , using Pseudomonas putida F39/D as a whole-cell biocatalytic system (Scheme ). , Reduced diol 2 was obtained in 90% through selective hydrogenation with diimide generated in situ . Protection of the diol functionality as acetonide followed by ozonolysis in the presence of NaHCO 3 , using DMS in the reductive step, afforded ester–aldehyde 4 in 76% combined yield …”

General Method for the Synthesis of (−)-Conduritol C and Analogs from Chiral Cyclohexadienediol Scaffolds

“…Similarly, the treatment of 8 under Prevost conditions resulted in the formation of isomer 9a (major product), as reported earlier [ 17 ]. Complete stereocontrol in the introduction of the following hydroxyl groups could be achieved by a direct attack with 10% aqueous NaOH in THF to the vinylic epoxide intermediate 10 , leading to enantiomerically pure compound 11 [ 18 ]. Its absolute stereochemistry was confirmed by X-ray diffraction analysis ( Figure 2 a).…”

Achievements, Challenges, and Scope of Thirty Years of Work on the Biotransformation of Arenes and Their Synthetic Applications

“…In summary, a series of highly functionalized, polyoxygenated chiral enones, 34, 36-40, with potential applications as synthetic intermediates were synthesized via simple reactions in short sequences [71] Another set of basic enantiopure synthons of interest to us was constituted by the α-heterosubstituted cyclohexanones, which are potential starting materials in the preparation of bengamides . [72] In this regard, a series of α-chloro-, α-hydroxy-, and α-azidocyclohexanones was chemoenzymatically prepared from chlorobenzene. The sequence started with the toluene dioxygenase-mediated oxidation of chlorobenzene to give enantiopure cis-diol 1 a, which was regioselectively reduced with diimide prepared in situ, protected as an acetonide and further epoxidized with m-CPBA to give the chlorooxirane 41 as a single isomer in 65% yield (Scheme 14).…”