In:
Chemistry – A European Journal, Wiley, Vol. 22, No. 1 ( 2016-01-04), p. 144-152
Abstract:
The stereoselective synthesis of ε‐isomers of dimethyl esters of 1,3‐diaminotruxillic acid in three steps is reported. The first step is the ortho ‐palladation of ( Z )‐2‐aryl‐4‐aryliden‐5(4 H )‐oxazolones 1 to give dinuclear complexes 2 with bridging carboxylates. The reaction occurs through regioselective activation of the ortho ‐CH bond of the 4‐arylidene ring in carboxylic acids. The second step is the [2+2]‐photocycloaddition of the CC exocyclic bonds of the oxazolone skeleton in 2 to afford the corresponding dinuclear ortho ‐palladated cyclobutanes 3 . This key step was performed very efficiently by using LED light sources with different wavelengths (465, 525 or 625 nm) in flow microreactors. The final step involved the depalladation of 3 by hydrogenation in methanol to afford the ε‐1,3‐diaminotruxillic acid derivatives as single isomers.
Type of Medium:
Online Resource
ISSN:
0947-6539
,
1521-3765
DOI:
10.1002/chem.201503742
Language:
English
Publisher:
Wiley
Publication Date:
2016
detail.hit.zdb_id:
1478547-X
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