scholarly journals Modification of Polyhedral Oligomeric Silsesquioxanes (POSS) Molecules by Ruthenium Catalyzed Cross Metathesis

Molecules ◽  
2018 ◽  
Vol 23 (7) ◽  
pp. 1722 ◽  
Author(s):  
Justyna Czaban-Jóźwiak ◽  
Łukasz Woźniak ◽  
Artur Ulikowski ◽  
Katarzyna Kwiecińska ◽  
Adam Rajkiewicz ◽  
...  
Keyword(s):  
Ruthenium Complexes ◽  
Polyhedral Oligomeric Silsesquioxanes ◽  
Ru Catalyst ◽  
Cross Metathesis

The scope of ruthenium (Ru)-catalyzed cross metathesis (CM) of allyl-decorated polyhedral oligomeric silsesquioxanes (POSS) was explored. A variety of different commercial and non-commercial ruthenium complexes were tested to determine that the nitro-activated Ru catalyst is optimal for this transformation. The reported transformation was used to prepare selected hybrid steroid-POSS compounds.

scholarly journals Application of olefin metathesis in the synthesis of functionalized polyhedral oligomeric silsesquioxanes (POSS) and POSS-containing polymeric materials

2019 ◽  
Vol 15 ◽  
pp. 310-332 ◽  
Author(s):  
Patrycja Żak ◽  
Cezary Pietraszuk
Keyword(s):  
Olefin Metathesis ◽  
Ring Opening ◽  
Polymeric Materials ◽  
Acyclic Diene Metathesis ◽  
Polyhedral Oligomeric Silsesquioxanes ◽  
Ring Opening Metathesis Polymerization ◽  
Metathesis Polymerization ◽  
Cross Metathesis ◽  
Terminal Olefins ◽  
Synthesized Materials

This mini-review summarizes the applications of olefin metathesis in synthesis and functionalization of polyhedral oligomeric silsesquioxanes (POSS) and POSS-containing polymeric materials. Three types of processes, i.e., cross metathesis (CM) of vinyl-substituted POSS with terminal olefins, acyclic diene metathesis (ADMET) copolymerization of divinyl-substituted POSS with α,ω-dienes and ring-opening metathesis polymerization (ROMP) of POSS-substituted norbornene (or other ROMP susceptible cycloolefins) are discussed. Emphasis was put on the synthetic and catalytic aspects rather than on the properties and applications of synthesized materials.

Terminal conjugated dienes via a ruthenium-catalyzed cross-metathesis/elimination sequence: application to renewable resources

2014 ◽  
Vol 4 (7) ◽  
pp. 2064-2071 ◽  
Author(s):  
Hallouma Bilel ◽  
Naceur Hamdi ◽  
Fethi Zagrouba ◽  
Cédric Fischmeister ◽  
Christian Bruneau
Keyword(s):  
Renewable Resources ◽  
Ruthenium Complexes ◽  
Conjugated Dienes ◽  
Cross Metathesis

Two-step synthesis of terminal 1,3-dienes catalyzed by two different ruthenium complexes.

Developments in Alkene Metathesis

2011 ◽  
Author(s):  
Douglass Taber
Keyword(s):  
Protein A ◽  
Ru Catalyst ◽  
Cross Metathesis ◽  
University Of Oxford ◽  
Ru Complex ◽  
Northwestern University ◽  
Allyl Sulfide ◽  
Aqueous Conditions ◽  
The University ◽  
Allyl Sulfides

Hervé Clavier and Steven P. Nolan, now at St. Andrew’s University, found (Adv. Synth. Cat. 2008, 350, 2959) that the indenylidene Ru complex 1 was an excellent pre-catalyst for alkene metathesis. A combination of 1 and the ligand 2 effected cross metathesis of 3 and 4 in just 15 minutes under microwave heating. Robert H. Grubbs of Caltech designed (Organic Lett. 2008, 10, 2693) the Ru catalyst 6 for the preparation of tri- and tetrasubstituted alkenes, as illustrated by the conversion of 7 to 8. The catalyst 6 also worked well for cross metathesis and ring opening metathesis polymerization (ROMP). For some biological applications, it would be desirable to run alkene cross metathesis under aqueous conditions. Benjamin G. Davis of the University of Oxford observed (J. Am. Chem. Soc. 2008, 130, 9642) that allyl sulfides such as 9 were unusually reactive in cross metathesis. Indeed, aqueous cross methathesis with such an allyl sulfide incorporated in a protein worked well, although added MgCl2 was required. The protein, a serine protease, maintained its activity after cross metathesis. α,β-Unsaturated thioesters such as 14 are excellent substrates for, inter alia, enantioselective Cu-catalyzed conjugate addition of Grignard reagents. Adriaan J. Minnaard and Ben L. Feringa of the University of Groningen found (J. Org. Chem. 2008, 73, 5651) that the thioacrylate 13 was an excellent substrate for cross methathesis, allowing ready preparation of 14 . Although alkene metathesis is often run in CH2Cl2 , benzene or toluene, these are not necessarily the optimal solvents. Siegfried Blechert of the TU Berlin established (Tetrahedron Lett. 2008, 49, 5968) that for the difficult cyclization of 16 to 17, hexafluorobenzene worked particularly well. The extended conformation (illustrated for 18) of an ester is more stable than the lactone conformation by about 5 kcal/mol. It is therefore not surprising that SonBinh T. Nguyen of Northwestern University observed (Organic Lett. 2008, 10, 5613) that attempted ring-closing metathesis of 18 gave only the dimer 20. On addition of the bulky Lewis acid 21, which can complex 18 in the lactone conformation, the reaction delivered the desired monomer 19. This should be a generally useful strategy for the cyclization of difficult ester substrates.

scholarly journals Cyclic Alkyl Amino Ruthenium Complexes—Efficient Catalysts for Macrocyclization and Acrylonitrile Cross Metathesis

ACS Catalysis ◽  
2017 ◽  
Vol 7 (8) ◽  
pp. 5443-5449 ◽  
Author(s):  
Rafał Gawin ◽  
Andrzej Tracz ◽  
Michał Chwalba ◽  
Anna Kozakiewicz ◽  
Bartosz Trzaskowski ◽  
...  
Keyword(s):  
Ruthenium Complexes ◽  
Cross Metathesis

Functionalization vs. degradation of 1,4-polybutadiene by ruthenium complex catalyzed reaction with vinylsilanes

2001 ◽  
Vol 79 (5-6) ◽  
pp. 775-779 ◽  
Author(s):  
Bogdan Marciniec ◽  
Ewa Malecka ◽  
Jacek Gulinski ◽  
Monika Grundwald-Wyspianska ◽  
Mariusz Lewandowski
Keyword(s):  
Ruthenium Complex ◽  
Ruthenium Complexes ◽  
Ruthenium Catalysts ◽  
Cross Metathesis ◽  
Higher Temperature ◽  
Partial Degradation

Polybutadiene (I) containing 91% of 1,4-(cis-trans) units and 9% of 1,2-units in the presence of vinyltriethoxysilane (II) and ruthenium catalysts RuCl2(PPh3)3 (III), RuHCl(CO)(PPh3)3 (IV), and [RuCl2(CO)3]2 (V) at 100-130°C undergoes functionalization and (or) partial degradation as an effect of competitive silylative coupling of =C-H and cross-metathesis of I with II. Significant degradation of I occurs at lower temperatures (100-110°C) (particularly when the process is carried out in air), but exclusive functionalization of I is observed at higher temperature (120-130°C) regardless of the atmosphere (air or argon) used.Key words: functionalization, degradation, polybutadiene, ruthenium complexes.

Cross-metathesis of vinyltriethoxysilane with olefins catalyzed by ruthenium complexes

1991 ◽  
Vol 65 (1-2) ◽  
pp. 113-125 ◽  
Author(s):  
Zenon Foltynowicz ◽  
Bogdan Marciniec ◽  
Cezary Pietraszuk
Keyword(s):  
Ruthenium Complexes ◽  
Cross Metathesis
Sign in / Sign up

Export Citation Format

Share Document