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Diversity-oriented synthesis based on the DPPP-catalyzed mixed double-Michael reactions of electron-deficient acetylenes and β-amino alcohols.

Fan YC, Kwon O - Molecules (2011)

Bottom Line: In this study, we prepared oxizolidines through 1,3-bis(diphenylphosphino)-propane (DPPP)-catalyzed mixed double-Michael reactions of β-amino alcohols with electron-deficient acetylenes.To demonstrate the applicability of mixed double-Michael reactions for the preparation of five-membered-ring heterocycles, we prepared 60 distinct oxazolidines from five β-amino alcohols and 12 electron-deficient acetylenes.We synthesized 36 of these 60 oxazolidines in enantiomerically pure form from proteinogenic amino acid-derived β-amino alcohols.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA.

ABSTRACT
In this study, we prepared oxizolidines through 1,3-bis(diphenylphosphino)-propane (DPPP)-catalyzed mixed double-Michael reactions of β-amino alcohols with electron-deficient acetylenes. These reactions are very suitable for the diversity-oriented parallel syntheses of oxizolidines because: (i) they are performed under mild metal-free conditions and (ii) the products are isolated without complicated work-up. To demonstrate the applicability of mixed double-Michael reactions for the preparation of five-membered-ring heterocycles, we prepared 60 distinct oxazolidines from five β-amino alcohols and 12 electron-deficient acetylenes. We synthesized 36 of these 60 oxazolidines in enantiomerically pure form from proteinogenic amino acid-derived β-amino alcohols.

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DPPP-Catalyzed Mixed Double-Michael Reactions.
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Figure 2: DPPP-Catalyzed Mixed Double-Michael Reactions.

Mentions: To overcome poor efficiency and the inability to incorporate other heteroatoms such as nitrogen and sulfur, in the phosphine-catalyzed double-Michael reactions, we set out to develop a route to generate various heterocyclic compounds under general and robust phosphine catalysis conditions. By employing DPPP as the catalyst, we have synthesized functionalized oxazolidines, thiazolidines, and pyrrolidines in high efficiency (Scheme 1) [30]. By employing dinucleophiles tethered through aromatic rings, we have obtained indolines, dihydropyrrolopyridines, benzimidazolines, tetrahydroquinolines, tetrahydroisoquinolines, dihydrobenzo-1,4-oxazines, and dihydrobenzo-3,1-oxazines using our developed mixed double-Michael strategy [31].


Diversity-oriented synthesis based on the DPPP-catalyzed mixed double-Michael reactions of electron-deficient acetylenes and β-amino alcohols.

Fan YC, Kwon O - Molecules (2011)

DPPP-Catalyzed Mixed Double-Michael Reactions.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4126835&req=5

Figure 2: DPPP-Catalyzed Mixed Double-Michael Reactions.
Mentions: To overcome poor efficiency and the inability to incorporate other heteroatoms such as nitrogen and sulfur, in the phosphine-catalyzed double-Michael reactions, we set out to develop a route to generate various heterocyclic compounds under general and robust phosphine catalysis conditions. By employing DPPP as the catalyst, we have synthesized functionalized oxazolidines, thiazolidines, and pyrrolidines in high efficiency (Scheme 1) [30]. By employing dinucleophiles tethered through aromatic rings, we have obtained indolines, dihydropyrrolopyridines, benzimidazolines, tetrahydroquinolines, tetrahydroisoquinolines, dihydrobenzo-1,4-oxazines, and dihydrobenzo-3,1-oxazines using our developed mixed double-Michael strategy [31].

Bottom Line: In this study, we prepared oxizolidines through 1,3-bis(diphenylphosphino)-propane (DPPP)-catalyzed mixed double-Michael reactions of β-amino alcohols with electron-deficient acetylenes.To demonstrate the applicability of mixed double-Michael reactions for the preparation of five-membered-ring heterocycles, we prepared 60 distinct oxazolidines from five β-amino alcohols and 12 electron-deficient acetylenes.We synthesized 36 of these 60 oxazolidines in enantiomerically pure form from proteinogenic amino acid-derived β-amino alcohols.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA.

ABSTRACT
In this study, we prepared oxizolidines through 1,3-bis(diphenylphosphino)-propane (DPPP)-catalyzed mixed double-Michael reactions of β-amino alcohols with electron-deficient acetylenes. These reactions are very suitable for the diversity-oriented parallel syntheses of oxizolidines because: (i) they are performed under mild metal-free conditions and (ii) the products are isolated without complicated work-up. To demonstrate the applicability of mixed double-Michael reactions for the preparation of five-membered-ring heterocycles, we prepared 60 distinct oxazolidines from five β-amino alcohols and 12 electron-deficient acetylenes. We synthesized 36 of these 60 oxazolidines in enantiomerically pure form from proteinogenic amino acid-derived β-amino alcohols.

Show MeSH
Related in: MedlinePlus