Selenophosphoramide-catalyzed diamination and oxyamination of alkenes

Tabor, John R.; Obenschain, Derek C.; Michael, Forrest E.

doi:10.1039/c9sc05335b

Cited by 21 publications

(10 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In a similar manner, analogous complexes of these ligands with selenium, i.e., phosphine selenides and selenoureas, which are trivial to generate from the corresponding phosphines and imidazolium salts, might also serve as more effective catalysts. Indeed, we and others have recently shown that these complexes can be used to control the selectivity of selenium-catalyzed reactions. − Gratifyingly, phosphine selenide catalysts did afford the desired allylic amination product, with 15 mol % tricyclohexylphosphine selenide (Cy 3 PSe) proving to be the most convenient and effective catalyst. The quantity of catalyst could be reduced further to 5 mol % with only a moderate drop in yield.…”

Section: Resultsmentioning

confidence: 99%

Catalytic Metal-free Allylic C–H Amination of Terpenoids

et al. 2020

Self Cite

View full text Add to dashboard Cite

The selective replacement of C–H bonds in complex molecules, especially natural products like terpenoids, is a highly efficient way to introduce new functionality and/or couple fragments. Here, we report the development of a new metal-free allylic amination of alkenes that allows the introduction of a wide range of nitrogen functionality at the allylic position of alkenes with unique regioselectivity and no allylic transposition. This reaction employs catalytic amounts of selenium in the form of phosphine selenides or selenoureas. Simple sulfonamides and sulfamates can be used directly in the reaction without the need to prepare isolated nitrenoid precursors. We demonstrate the utility of this transformation by aminating a large set of terpenoids in high yield and regioselectivity.

show abstract

Section: Resultsmentioning

confidence: 99%

Catalytic Metal-free Allylic C–H Amination of Terpenoids

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…23,24 In addition, Michael and co-workers found that a selenophosphoramide can generate a seleniranium ion catalytically, while also acting as a good leaving group for a secondary nucleophilic addition (Scheme 3e). 26 This method comprises several examples using unsaturated esters and sulfonimides for the formation of racemic 1,2-amino alcohol precursors in fair to good yields. Interestingly, this method was disclosed as a serendipitous discovery within the context of an alkene diamination investigation.…”

Section: ■ Backgroundmentioning

confidence: 99%

Catalytic, Enantioselective Syn-Oxyamination of Alkenes

2021

View full text Add to dashboard Cite

The chemo-, regio-, diastereo-, and enantioselective 1,2-oxyamination of alkenes using selenium(II/IV) catalysis with a chiral diselenide catalyst is reported. This method uses Ntosylamides to generate oxazoline products that are useful both as protected 1,2-amino alcohol motifs and as chiral ligands. The reaction proceeds in good yields with excellent enantio-and diastereoselectivity for a variety of alkenes and pendant functional groups such as sulfonamides, alkyl halides, and glycol-protected ketones. Furthermore, the rapid generation of oxazoline products is demonstrated in the expeditious assembly of chiral PHOX ligands as well as diversely protected amino alcohols.

show abstract

“…Kürzlich haben Denmark und Mitarbeitende sowie Michael und Mitarbeitende dieses Konzept erweitert, indem sie katalytische Methoden entwarfen, die jeweils eine direkte und teilweise asymmetrische syn ‐1,2‐Dichlorierung, syn ‐1,2‐Oxylierung oder syn ‐ bzw. anti ‐1,2‐Diaminierung von Alkenen ermöglichten [14–17] …”

Section: Introductionunclassified

Wasserstoffbrücken‐modulierte Nukleofugalität von Se^III‐Spezies ermöglicht photoredox‐katalytische Semipinakol‐Prozesse

et al. 2022

View full text Add to dashboard Cite

Die Aktivierung chemischer Bindungen mittels H‐Brücken‐Wechselwirkungen zwischen elektronegativen Elementen wie z. B. Stickstoff und Sauerstoff stellt eine hoch wirkungsvolle Taktik in der modernen Katalyseforschung dar. Dem gegenüber sind artverwandte Katalyseverfahren, in denen schwerere, weniger elektronegative Elemente wie Selen an der Ausbildung von H‐Brücken beteiligt sind, beispielsweise zur oxidativen Aktivierung angrenzender C‐Se σ ${{\rm \sigma }}$ ‐Bindung, praktisch unerforscht. Klassische Strategien zur Erhöhung der Nukleofugalität von Selanylgruppen beruhen auf der oxidativen Addition von Elektrophilen an SeII‐Zentren, was in der Regel die Eliminierung der resultierenden SeIV‐Spezies zur Folge hat. Katalytische Verfahren, in denen diese SeIV‐Nukleofuge substituiert anstatt eliminiert werden, sind sehr selten und waren bislang nicht auf die Knüpfung von C‐C‐Bindungen anwendbar. Wie in der vorliegenden Arbeit erstmals gezeigt wird, können durch die Kombination von O−H⋅⋅⋅Se H‐Brücken‐Wechselwirkungen und katalytischer Einelektronenoxidation stabilisierte SeIII‐Nukleofuge erzeugt werden, die die Bildung neuer C‐C‐ σ ${{\rm \sigma }}$ ‐Bindungen mittels einer Typ I Semipinakol‐Umlagerung in hoher Ausbeute und ausgezeichneter Selektivität ermöglichen.

show abstract

Selenophosphoramide-catalyzed diamination and oxyamination of alkenes

Abstract: Scavenging fluoride from a selenophosphoramide-catalyzed alkene oxidation reaction suppresses the known syn-elimination pathway, enabling alkene diamination/oxyamination reactions via substitution.

Cited by 21 publications

References 40 publications

Catalytic Metal-free Allylic C–H Amination of Terpenoids

Catalytic Metal-free Allylic C–H Amination of Terpenoids

Catalytic, Enantioselective Syn-Oxyamination of Alkenes

Wasserstoffbrücken‐modulierte Nukleofugalität von Se^III‐Spezies ermöglicht photoredox‐katalytische Semipinakol‐Prozesse

Contact Info

Product

Resources

About

Selenophosphoramide-catalyzed diamination and oxyamination of alkenes

Abstract: Scavenging fluoride from a selenophosphoramide-catalyzed alkene oxidation reaction suppresses the known syn-elimination pathway, enabling alkene diamination/oxyamination reactions via substitution.

Cited by 21 publications

References 40 publications

Catalytic Metal-free Allylic C–H Amination of Terpenoids

Catalytic Metal-free Allylic C–H Amination of Terpenoids

Catalytic, Enantioselective Syn-Oxyamination of Alkenes

Wasserstoffbrücken‐modulierte Nukleofugalität von SeIII‐Spezies ermöglicht photoredox‐katalytische Semipinakol‐Prozesse

Contact Info

Product

Resources

About

Wasserstoffbrücken‐modulierte Nukleofugalität von Se^III‐Spezies ermöglicht photoredox‐katalytische Semipinakol‐Prozesse