| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1345745 | Tetrahedron: Asymmetry | 2006 | 7 Pages |
An efficient chemoenzymatic route for the synthesis of optically active substituted indolines has been developed. Different lipases have been tested in the alkoxycarbonylation of these secondary amines, Candida antarctica lipase A (CAL-A) was found to be the best biocatalyst for 2-substituted-indolines, and C. antarctica lipase B (CAL-B) for 3-methylindoline. The combination of lipases with a variety of allyl carbonates and tert-butyl methyl ether (TBME) as solvent has allowed the isolation of the carbamate and amine derivatives with a high level of enantiopurity.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide
(S)-(−)-2-MethylindolineC9H11NEe = 99% (HPLC, Chiralcel OD)[α]D20=-16.3 (c 0.5, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: S
(R)-(−)-2-Methylindoline allyl carbamateC13H15NO2Ee = 99% (HPLC, Chiralcel OD)[α]D20=-47.4 (c 0.5, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: R
(S)-(+)-2-PhenylindolineC14H13NEe = 97% (HPLC, Chiralcel OD)[α]D20=+65.4 (c 0.5, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: S
(R)-(−)-2-Phenylindoline allyl carbamateC18H17NO2Ee = 99% (HPLC, Chiralcel OB-H)[α]D20=-93.0 (c 0.5, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: R
(S)-(−)-2-Methyl-5-methoxyindolineC10H13NOEe = 99% (HPLC, Chiralcel OD)[α]D20=-14.2 (c 0.5, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: S
(R)-(−)-2-Methyl-5-methoxyindoline allyl carbamateC14H17NO2Ee = 95%[α]D20=-54.6 (c 0.5, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: R
(S)-(−)-5-Fluoro-2-methylindolineC19H10FNEe = 99% (HPLC, Chiralcel OD)[α]D20=-10.1 (c 0.5, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: S
(R)-(−)-5-Fluoro-2-methylindoline allyl carbamateC13H14FNO2Ee = 99% (HPLC, Chiralcel OB-H)[α]D20=-37.3 (c 0.5, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: R
(R)-(−)-3-MethylindolineC9H11NEe = 99% (HPLC, Chiralcel OB-H)[α]D20=-30.2 (c 0.25, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: R
(S)-(−)-3-Methylindoline allyl carbamateC13H15NO2Ee = 97% (HPLC, Chiralcel OB-H)[α]D20=+21.2 (c 0.5, CHCl3)Source of chirality: enzymatic kinetic resolutionAbsolute configuration: S
