Generation of Cycloalkylidene Carbenes via Exo-Type Cyclization of Alkynyllithiums Bearing Remote Leaving Group

Harada, Toshiro; Iwazaki, Katsuhiro; Otani, Takeshi; Oku, Akira

doi:10.1021/jo981411p

Cited by 32 publications

(10 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Inspired by the work of Harada and co‐workers, who could cyclize a variety of hexynyl tosylates, such as 1 a , via the corresponding lithium acetylides,6a we used 1 a as a test system for a possible gold‐catalyzed process. As mentioned earlier, only the σ‐activation should be addressed by the gold catalyst; therefore, we used gold propyne acetylides as precursors that do not form cationic gold complexes.…”

Section: Methodsmentioning

confidence: 99%

Nanorattles or Yolk–Shell Nanoparticles—What Are They, How Are They Made, and What Are They Good For?

Priebe

Fromm

2014

Chemistry A European J

131

View full text Add to dashboard Cite

The development of nanotechnology has led to the design of cutting-edge nanomaterials with increasing levels of complexity. Although "traditional" solid, uniform nanoparticles are still the most frequently reported structures, new generations of nanoparticles have been constantly emerging over the last several decades. The outcome of this nano-art extends beyond nanomaterials with alternative compositions and/or morphologies. The current state-of-the-art allows for the design of nanostructures composed of different building blocks that exhibit diverse properties. Furthermore, those properties can be a reflection of either individual features, which are characteristic of a particular building block alone, and/or synergistic effects resulting from interactions between building blocks. Therefore, the unique structures as well as the outstanding properties of nanorattles have attracted increasing attention for possible biomedical and industrial applications. Although these nanoparticles resemble core-shell particles, they have a distinctive feature, which is a presence of a void that provides a homogenous environment for the encapsulated core. In this Review, we give a comprehensive insight into the fabrication of nanorattles. A special emphasis is put on the choice of building blocks as well as the choice of preparation method, because those two aspects further influence properties and thus possible future applications, which will also be discussed.

show abstract

Section: Methodsmentioning

confidence: 99%

Nanorattles or Yolk–Shell Nanoparticles—What Are They, How Are They Made, and What Are They Good For?

Priebe

Fromm

2014

Chemistry A European J

131

View full text Add to dashboard Cite

show abstract

“…Angeregt durch die Arbeiten von Haradas Gruppe, die verschiedene Hexinyltosylate wie 1 a über die jeweiligen Lithiumacetylide cyclisieren konnte,6a nutzten wir 1 a als Testsystem für eine mögliche Goldkatalyse. Wie zuvor erwähnt, sollte nur die σ‐Aktivierung durch den Goldkatalysator adressiert werden; daher verwendeten wir Propinylgoldacetylide als Vorstufen ohne kationischen Teil.…”

Section: Methodsunclassified

Cyclisierung von Goldacetyliden: Synthese von Vinylsulfonaten über Vinylidengold‐Komplexe

et al. 2014

View full text Add to dashboard Cite

Verschieden substituierte terminale Alkine mit Sulfonat-Abgangsgruppen in passender Entfernung wurden in Gegenwart von Propinylgold(I)-Präkatalysatoren umgesetzt. Nach der Bildung eines Goldacetylids findet eine Cyclisierung über das b-Kohlenstoffatom des Goldacetylids statt. Der Mechanismus dürfte ähnlich zu dem der dualen Goldkatalyse sein, aber im Fall der neuen Substrate wird nur ein Goldzentrum für die Aktivierung des Substrates bençtigt. Nach Bildung eines Vinylidengold-Komplexes, der ein enges Kontaktionenpaar mit der Sulfonat-Abgangsgruppe bildet, liefert eine Rekombination der beiden Teile Vinylsulfonate, die wertvolle Zielverbindungen sind und z. B. als Vorstufen in Kreuzkupplungen fungieren kçnnen. Schema 1. Oben: dualer Aktivierungsweg zu Vinylidenen; unten: geplante Acetylid-und-Abgangsgruppen-Strategie als Weg zu Vinylidenen.

show abstract

“…In our hands, the reported synthesis of 4 proved tedious. Therefore a dianion alkylation based construction was investigated.…”

mentioning

confidence: 91%

Stille Couplings Catalytic in Tin: A “Sn−F” Approach

Maleczka

Gallagher

2001

Org. Lett.

View full text Add to dashboard Cite

A new tin recycling method for Stille couplings catalytic in tin is reported. PMHS made hypercoordinate by KF((aq)) allows Me(3)SnH to be efficiently recycled during a Pd(0)-catalyzed hydrostannation/Stille cascade. Relative to previously disclosed protocols, reaction times are shorter and because this process is believed to proceed through a Me(3)SnF intermediate the hazards and problems associated with trimethyltins are also diminished.[reaction: see text]

show abstract

Generation of Cycloalkylidene Carbenes via Exo-Type Cyclization of Alkynyllithiums Bearing Remote Leaving Group

Cited by 32 publications

References 34 publications

Nanorattles or Yolk–Shell Nanoparticles—What Are They, How Are They Made, and What Are They Good For?

Nanorattles or Yolk–Shell Nanoparticles—What Are They, How Are They Made, and What Are They Good For?

Cyclisierung von Goldacetyliden: Synthese von Vinylsulfonaten über Vinylidengold‐Komplexe

Stille Couplings Catalytic in Tin: A “Sn−F” Approach

Contact Info

Product

Resources

About