Alkyne metathesis with in situ catalysts: W(CO)6 and 4-chlorophenol are efficient in the formation of poly(para-phenyleneethynylene)s

Generation of chromium Schrock carbene equivalents from gem-dichromiomethanes was suggested in the transformation of 5-alkynones via carbene/alkyne metathesis followed by cyclization induced by capturing with polar CO bonds.

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Recent Advances in Ruthenium-Catalyzed Carbene/Alkyne Metathesis (CAM) Transformations

Synlett ◽

10.1055/s-0039-1690861 ◽

2020 ◽

Vol 31 (12) ◽

pp. 1147-1157 ◽

Cited By ~ 2

Author(s):

Carlos Saá ◽

Damián Padín ◽

Jesús A. Varela

Keyword(s):

Hydride Transfer ◽

Synthetic Chemistry ◽

Dft Studies ◽

Alkyne Metathesis ◽

Efficient Procedure ◽

Recent Advances ◽

In Situ Generation

Carbene intermediates have shown versatile applications in modern synthetic chemistry. Catalytic ruthenium carbene/alkyne metathesis (CAM) with readily available substrates renders an efficient procedure for the in situ generation of ruthenium vinyl carbene intermediates. Here, recent advances in synthetic applications of ruthenium-catalyzed carbene/alkyne metathesis (CAM) are highlighted.1 Introduction2 Ruthenium Vinyl Carbenes through Carbene/Alkyne Metathesis (CAM)3 Nonpolar Transformations of Ruthenium Vinyl Carbenes4 Polar Transformations of Ruthenium Vinyl Carbenes4.1 Intramolecular Ruthenium-Catalyzed [1,5]- and [1,6]-Hydride Transfer/Cyclization4.2 Heterocyclizations of Alkynals and Alkynones4.3 Heterocyclizations of ortho-(Alkynyloxy)benzylamines5 DFT Studies on the Stereoselectivity of the CAM Reaction6 Conclusions

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In situ Mo(CO)₆-based catalysts for alkyne metathesis: Silanols vs phenols as co-catalysts under thermal and photochemical activation

Catalysis Communications ◽

10.1016/j.catcom.2020.105944 ◽

2020 ◽

Vol 138 ◽

pp. 105944

Author(s):

Maciej Zaranek ◽

Jakub Robaszkiewicz ◽

Iwona Janica ◽

Regis M. Gauvin ◽

Piotr Pawluć ◽

...

Keyword(s):

Alkyne Metathesis ◽

Co Catalysts ◽

Photochemical Activation

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Rendez vous with Saturn's rings

International Astronomical Union Colloquium ◽

10.1017/s0252921100101885 ◽

1984 ◽

Vol 75 ◽

pp. 743-759 ◽

Cited By ~ 2

Author(s):

Kerry T. Nock

Keyword(s):

Solar Energy ◽

Electric Propulsion ◽

Power Source ◽

Propulsion System ◽

Low Thrust ◽

Ring Plane ◽

The Earth ◽

Total Impulse ◽

Saturn's Rings

ABSTRACTA mission to rendezvous with the rings of Saturn is studied with regard to science rationale and instrumentation and engineering feasibility and design. Future detailedin situexploration of the rings of Saturn will require spacecraft systems with enormous propulsive capability. NASA is currently studying the critical technologies for just such a system, called Nuclear Electric Propulsion (NEP). Electric propulsion is the only technology which can effectively provide the required total impulse for this demanding mission. Furthermore, the power source must be nuclear because the solar energy reaching Saturn is only 1% of that at the Earth. An important aspect of this mission is the ability of the low thrust propulsion system to continuously boost the spacecraft above the ring plane as it spirals in toward Saturn, thus enabling scientific measurements of ring particles from only a few kilometers.

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