Thiourea catalysed reduction of α-keto substituted acrylate compounds using Hantzsch ester as a reducing agent in water

Abstract

The first method for the reduction of a-keto substituted acrylate compounds by Hantzsch ester in water under the catalysis of thiourea has been developed. The products were isolated in moderate to high yields (38-95%). These products are important intermediates in the synthesis of a series of natural products and other biologically active molecules.

Transition Metal‐Free Reduction of Activated Alkenes Using a Living Microorganism

“…This avoids the use of expensive exogenous reagents and circumvents the need for largescale enzyme overexpression and purification, as purified enzymes must be continuously replenished by re-synthesis in the same way as ac hemical reagent. Them ild reaction conditions and absence of any transition metals also add to the appeal of this process.T his stands in stark contrast to modern abiotic methods for transition metal-free alkene reduction in synthetic organic chemistry,r ecent examples of which include:1 )transfer hydrogenation using diphenylamine,t riethylsilane,a nd the electrophilic cationic phosphonium catalyst [(C 6 F 5 ) 3 PF)] + [B(C 6 F 5 ) 4 ] À ;2 )thiourea organocatalysis using aH antzsch ester in refluxing H 2 O; and 3) the use of NaAlH 4 /C nanocomposites and 100 bar H 2 (g) in organic solvent at 150 8 8Cf or 48 h. [12] Theb iocompatibility of whole-cell reactions is also important, yet is rarely considered in the field of biocatalysis.B eyond substrate localization effects,biocompatible reactions can also be readily integrated into de novo metabolic pathways for renewable chemical production in microbial cells.…”