Enantiomerically pure cage-shaped (1S,4S,5R)-4-hydroxy-2,6-diazabicyclo[3.3.0]octane and (1S,4R,5R)-4-hydroxy-2-oxa-6-azabicyclo[3.3.0]octane: Synthesis and test for enantioselective catalysis

Vorsicht geboten ist bei der Reduktion vicinaler Sulfonsäureester mit LiAlD4, denn die Reaktion nimmt einen unerwarteten stereochemischen Verlauf: Während bei der Substitution der einen Tosylat(Ts)‐Gruppe eine Inversion der Konfiguration am C‐Atom stattfindet, wird die andere unter Retention substituiert. Letzteres kann am besten mit einer doppelten Inversion unter Beteiligung der Nachbargruppe erklärt werden (siehe Schema). Ts=Toluol‐4‐sulfonyl.

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Cu,Ni, andPdMediated Homocoupling Reactions in Biaryl Syntheses: TheUllmann Reaction

Nelson

Crouch

2004

Organic Reactions

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The traditional Ullman reaction is the homocoupling of aromatic halides mediated by copper at elevated temperatures. Ullman first reported this reaction in 1901. Although the coupling conditions first reported are still widely used, a host of modifications have been made to these reactions. Some of these modifications include the use of activated and alternative metals, often resulting in much lower coupling temperatures. Nickel and palladium are the most utilized source of alternative metals, Periodic reviews have been published. This chapter covers the literature on copper, nickel, and palladium mediated homocoupling reactions in biaryl synthesis from 1901 to 2000. The focus of this chapter is the scope and limitation of these processes, preparation of the activated metal, and mechanism of the homocoupling process

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Enantiomerically pure cage-shaped (1S,4S,5R)-4-hydroxy-2,6-diazabicyclo[3.3.0]octane and (1S,4R,5R)-4-hydroxy-2-oxa-6-azabicyclo[3.3.0]octane: Synthesis and test for enantioselective catalysis

Cited by 24 publications

References 45 publications

Synthesis of Axially Chiral Biaryls by Atropo-Diastereoselective Cleavage of Configurationally Unstable Biaryl Lactones with Menthol-DerivedO-Nucleophiles

Synthesis of Axially Chiral Biaryls by Atropo-Diastereoselective Cleavage of Configurationally Unstable Biaryl Lactones with Menthol-DerivedO-Nucleophiles

Insekten-Desaturasen als einzigartige analytische Hilfsmittel zur Bestimmung des stereochemischen Verlaufs der Reduktion vicinaler Ditosylate mit Lithiumaluminiumdeuterid

Cu,Ni, andPdMediated Homocoupling Reactions in Biaryl Syntheses: TheUllmann Reaction

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