Sn-Beta zeolite as diastereoselective water-resistant heterogeneous Lewis-acid catalyst for carbon–carbon bond formation in the intramolecular carbonyl–ene reaction

2004 ◽  
pp. 550-551 ◽  
Author(s):  
Avelino Corma ◽  
Michael Renz
Keyword(s):  
Lewis Acid ◽  
Bond Formation ◽  
Acid Catalyst ◽  
Beta Zeolite ◽  
Carbon Bond ◽  
Ene Reaction ◽  
Carbon Carbon Bond ◽  
Lewis Acid Catalyst

Ruthenium-Catalyzed Carbon−Carbon Bond Formation between Propargylic Alcohols and Alkenes via the Allenylidene-Ene Reaction

2003 ◽  
Vol 125 (20) ◽  
pp. 6060-6061 ◽  
Author(s):  
Yoshiaki Nishibayashi ◽  
Youichi Inada ◽  
Masanobu Hidai ◽  
Sakae Uemura
Keyword(s):  
Bond Formation ◽  
Carbon Bond ◽  
Ene Reaction ◽  
Propargylic Alcohols ◽  
Carbon Carbon Bond

scholarly journals Multifunctional heterocyclic scaffolds for hybrid Lewis acid/Lewis base catalysis of carbon–carbon bond formation

Tetrahedron ◽  
2016 ◽  
Vol 72 (27-28) ◽  
pp. 3905-3916 ◽  
Author(s):  
Dennis Wiedenhoeft ◽  
Adam R. Benoit ◽  
Yibiao Wu ◽  
Jacob D. Porter ◽  
Elisia Meyle ◽  
...  
Keyword(s):  
Lewis Acid ◽  
Bond Formation ◽  
Lewis Base ◽  
Base Catalysis ◽  
Carbon Bond ◽  
Carbon Carbon Bond

scholarly journals The two-step mechanochemical synthesis of porphyrins

2014 ◽  
Vol 170 ◽  
pp. 59-69 ◽  
Author(s):  
Hannah Shy ◽  
Paula Mackin ◽  
Andrea S. Orvieto ◽  
Deepa Gharbharan ◽  
Geneva R. Peterson ◽  
...  
Keyword(s):  
Organic Solvent ◽  
Mechanochemical Synthesis ◽  
Bond Formation ◽  
Acid Catalyst ◽  
Solvent Free ◽  
Oxidizing Agent ◽  
Carbon Bond ◽  
Carbon Carbon Bond ◽  
Solvent Free Conditions ◽  
Porphyrin Synthesis

Porphyrin synthesis under solvent-free conditions represents the “greening” of a traditional synthesis that normally requires large amounts of organic solvent, and has hindered the industrial-scale synthesis of this useful class of molecules. We have found that the four-fold acid-catalysed condensation of aldehyde and pyrrole to yield a tetra-substituted porphyrin is possible through mechanochemical techniques, without a solvent present. This represents one of the still-rare examples of carbon–carbon bond formation by mechanochemistry. Specifically, upon grinding equimolar amounts of pyrrole and benzaldehyde in the presence of an acid catalyst, cyclization takes place to give reduced porphyrin precursors (reversible), which upon oxidation form tetraphenylporphyrin (TPP). The approach has been found to be suitable for the synthesis of a variety of meso-tetrasubstituted porphyrins. Oxidation can occur either by using an oxidizing agent in solution, to give yields comparable to those published for traditional methods of porphyrin synthesis, or through mechanochemical means resulting in a two-step mechanochemical synthesis to give slightly lower yields that are still being optimized. We are also working on “green” methods of porphyrin isolation, including entrainment sublimation, which would hopefully further reduce the need for large amounts of organic solvent. These results hold promise for the development of mechanochemical synthetic protocols for porphyrins and related classes of compounds.

Sign in / Sign up

Export Citation Format

Share Document