title: Chemo-Enzymatic Synthesis of Chiral Epoxides Ethyl and Methyl (S)-3-(Oxiran-2-yl)propanoates from Renewable Levoglucosenone: An Access to Enantiopure (S)-Dairy Lactone.
abstract: Chiral epoxides-such as ethyl and methyl (S)-3-(oxiran-2-yl)propanoates ((S)-1a/1b)-are valuable precursors in many chemical syntheses. Until recently, these compounds were synthesized from glutamic acid in four steps (deamination, reduction, tosylation and epoxide formation) in low to moderate overall yield (20%-50%). Moreover, this procedure requires some harmful reagents such as sodium nitrite ((eco)toxic) and borane (carcinogen). Herein, starting from levoglucosenone (LGO), a biobased chiral compound obtained through the flash pyrolysis of acidified cellulose, we propose a safer and more sustainable chemo-enzymatic synthetic pathway involving lipase-mediated Baeyer-Villiger oxidation, palladium-catalyzed hydrogenation, tosylation and treatment with sodium ethoxide/methoxide as key steps. This route afforded ethyl and methyl (S)-3-(oxiran-2-yl)propanoates in 57% overall yield, respectively. To demonstrate the potentiality of this new synthetic pathway from LGO, the synthesis of high value-added (S)-dairy lactone was undertaken from these epoxides and provided the target in 37% overall yield from LGO.
authors.affiliation: Chaire ABI-AgroParisTech, CEBB, 3 rue des Rouges Terres, 51110 Pomacle, France. florent.allais@agroparistech.fr.|Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Universit&#233; Paris-Saclay, RD10, 78026 Versailles Cedex, France. florent.allais@agroparistech.fr.
authors.forename: Aurélien A M
authors.initials: AA
authors.lastname: Peru
authors.affiliation: Chaire ABI-AgroParisTech, CEBB, 3 rue des Rouges Terres, 51110 Pomacle, France. florent.allais@agroparistech.fr.|Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Universit&#233; Paris-Saclay, RD10, 78026 Versailles Cedex, France. florent.allais@agroparistech.fr.
authors.forename: Amandine L
authors.initials: AL
authors.lastname: Flourat
authors.affiliation: Circa Group Pty Ltd., 34 Norkfolk Court, Coburg, 3058 Victoria, Australia. christian.gunawan@circagroup.com.au.
authors.forename: Christian
authors.initials: C
authors.lastname: Gunawan
authors.affiliation: Circa Group Pty Ltd., 34 Norkfolk Court, Coburg, 3058 Victoria, Australia. warwick.raverty@circagroup.com.au.
authors.forename: Warwick
authors.initials: W
authors.lastname: Raverty
authors.affiliation: School of Science and Technology, University of New England, Armidale, 2350 New South Wales, Australia. jevric.m@gmail.com.
authors.forename: Martyn
authors.initials: M
authors.lastname: Jevric
authors.affiliation: School of Science and Technology, University of New England, Armidale, 2350 New South Wales, Australia. ben.greatrex@une.edu.au.
authors.forename: Ben W
authors.initials: BW
authors.lastname: Greatrex
authors.affiliation: Chaire ABI-AgroParisTech, CEBB, 3 rue des Rouges Terres, 51110 Pomacle, France. florent.allais@agroparistech.fr.|UMR 782 GMPA, INRA, AgroParisTech, CNRS, Universit&#233; Paris-Saclay, Avenue Lucien Br&#233;tigni&#232;res, 78850 Thiverval-Grignon, France. florent.allais@agroparistech.fr.
authors.forename: Florent
authors.initials: F
authors.lastname: Allais
mesh_terms: D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry*; D004852:Epoxy Compounds / Q000138:chemical synthesis / Q000737:chemistry; D005947:Glucose / Q000031:analogs & derivatives* / Q000737:chemistry; D007783:Lactones / Q000737:chemistry*; D011422:Propionates / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D004852:Epoxy Compounds; D007783:Lactones; D011422:Propionates; C512757:1,6-anhydro-3,4-dideoxyhex-3-enopyran-2-ulose; D005947:Glucose
keywords: chirality; epoxide; flavor; levoglucosenone; total synthesis