Polymer-Assisted Synthesis of Single and Fused Diketomorpholines
Jazyk angličtina Země Spojené státy americké Médium print-electronic
Typ dokumentu časopisecké články, práce podpořená grantem
- Klíčová slova
- bromoketone, diketomorpholine, morpholine, serine, solid-phase synthesis,
- MeSH
- acylace MeSH
- alkylace MeSH
- cyklizace MeSH
- kyselina trifluoroctová chemie MeSH
- kyseliny karboxylové chemie MeSH
- molekulární struktura MeSH
- morfoliny chemická syntéza MeSH
- nitrobenzeny chemie MeSH
- oxaziny chemie MeSH
- polymery chemie MeSH
- silany chemie MeSH
- stereoizomerie MeSH
- techniky syntézy na pevné fázi metody MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- 4-nitrobenzenesulfonyl chloride MeSH Prohlížeč
- kyselina trifluoroctová MeSH
- kyseliny karboxylové MeSH
- morfoliny MeSH
- nitrobenzeny MeSH
- oxaziny MeSH
- polymery MeSH
- silany MeSH
- triethylsilane MeSH Prohlížeč
The synthesis of different diketomorpholines via N-acyl-3,4-dihydro-2 H-1,4-oxazine-3-carboxylic acids is reported in this article. The key intermediates were prepared using a convenient solid-phase synthesis starting from polymer-supported Ser( tBu)-OH. After subsequent sulfonylation with 4-nitrobenzenesulfonyl chloride (4-Nos-Cl), alkylation with an α-bromoketone, cleavage of the 4-Nos group and acylation with an α-halocarboxylic acids, acid-mediated cleavage from the resin yielded dihydrooxazine-3-carboxylic acids in high crude purities. Depending on the reaction conditions, exposure to base resulted in cyclization to either oxazino[3,4- c][1,4]oxazine-diones or 3-methylidenemorpholine-2,5-diones. Further reaction with triethylsilane-trifluoroacetic acid (TES/TFA) led to olefin reduction, in the case of oxazino[3,4- c][1,4]oxazine-dione with full control of the newly formed stereocenter.
Citace poskytuje Crossref.org
