Abstract
A series of 18 regio- and stereo-chemically diverse chiral non-racemic 1,2-, 1,3-, and 1,4-diamines have been synthesized from commercial (1S)-(+)-ketopinic acid and (1S)-(+)-10-camphorsulfonic acid. The structures of the diamines are all based on the D-(+)-camphor scaffold and feature isomeric diversity in terms of regioisomeric attachment of the primary and the tertiary amine function and the exo/endo-isomerism. Diamines were transformed into the corresponding noncovalent bifunctional thiourea organocatalysts, which have been evaluated for catalytic activity in the conjugative addition of 1,3-dicarbonyl nucleophiles (dimethyl malonate, acetylacetone, and dibenzoylmethane) to trans-β-nitrostyrene. The highest enantioselectivity was achieved in the reaction with acetylacetone as nucleophile using endo-1,3-diamine derived catalyst 52 (91.5:8.5 er). All new organocatalysts 48–63 have been fully characterized. The structures and the absolute configurations of eight intermediates and thiourea derivative 52 were also determined by X-ray diffraction.
Keywords
(+)-kafra;diamini;tiosečnina;bifunkcionalni organokatalizatorji;asimetrična sinteza;(+)-camphor;diamines;thiourea;bifunctional organocatalysts;asymmetric synthesis;
Data
Language: |
English |
Year of publishing: |
2020 |
Typology: |
1.01 - Original Scientific Article |
Organization: |
UL FKKT - Faculty of Chemistry and Chemical Technology |
UDC: |
547.415.1 |
COBISS: |
24479491
|
ISSN: |
1420-3049 |
Views: |
364 |
Downloads: |
57 |
Average score: |
0 (0 votes) |
Metadata: |
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Other data
Secondary language: |
Slovenian |
Secondary keywords: |
(+)-kafra;diamini;tiosečnina;bifunkcionalni organokatalizatorji;asimetrična sinteza; |
Type (COBISS): |
Article |
Pages: |
str. 1-22 |
Volume: |
ǂVol. ǂ25 |
Issue: |
ǂiss. ǂ13 |
Chronology: |
Jul. 2020 |
DOI: |
10.3390/molecules25132978 |
ID: |
14110128 |