Université de Fribourg

Heptacoordinate Co(II) catalyst for light-driven hydrogen production in fully aqueous medium

Lucarini, Fiorella ; Ruggi, Albert

In: CHIMIA International Journal for Chemistry, 2018, vol. 72, no. 4, p. 203–206

Photocatalytic hydrogen production is an appealing way to store solar energy as chemical fuel. The most studied molecular catalysts for H2 production are based on earth-abundant metals such as Ni, Co and Fe. Efforts have been recently focused on the design of Co complexes with distorted octahedral geometries induced by tetra- or pentapyridyl ligands. We synthesized a new Co(II) complex based...

Université de Fribourg

Functional metathesis catalyst through ring closing enyne metathesis: one pot protocol for living heterotelechelic polymers

Pal, Subhajit ; Lucarini, Fiorella ; Ruggi, Albert ; Kilbinger, Andreas F. M.

In: Journal of the American Chemical Society, 2018, vol. 140, no. 9, p. 3181–3185

Enyne ring closing metathesis has been used to synthesize functional group carrying metathesis catalysts from a commercial (Ru-benzylidene) Grubbs’ catalysts. The new Grubbs-type ruthenium carbene was used to synthesize living heterotelechelic ROMP polymers without any intermediate purification. Olefin metathesis with a mono substituted alkyne followed by ring closing metathesis with an...

Université de Fribourg

Hydrogen atom transfer (HAT) processes promoted by the quinolinimide-N-oxyl radical: a kinetic and theoretical study

DiLabio, Gino A. ; Franchi, Paola ; Lanzalunga, Osvaldo ; Lapi, Andrea ; Lucarini, Fiorella ; Lucarini, Marco ; Mazzonna, Marco ; Prasad, Viki Kumar ; Ticconi, Barbara

In: The Journal of Organic Chemistry, 2017, vol. 82, no. 12, p. 6133–6141

A kinetic study of the hydrogen atom transfer (HAT) reactions from a series of organic compounds to the quinolinimide-N-oxyl radical (QINO) was performed in CH3CN. The HAT rate constants are significantly higher than those observed with the phthalimide- N-oxyl radical (PINO) as a result of enthalpic and polar effects due to the presence of the N-heteroaromatic ring in QINO. The relevance of...

Université de Fribourg

Heptacoordinate Coii complex: a new architecture for photochemical hydrogen production

Lucarini, Fiorella ; Pastore, Mariachiara ; Vasylevskyi, Serhii ; Varisco, Massimo ; Solari, Euro ; Crochet, Aurelien ; Fromm, Katharina M. ; Zobi, Fabio ; Ruggi, Albert

In: Chemistry - A European Journal, 2017, p. -

The first heptacoordinate cobalt catalyst for light-driven hydrogen production in water has been synthesized and characterized. Photochemical experiments using [Ru(bpy)₃]²⁺ as photosensitizer gave a turnover number (TON) of 16300 mol H₂ (mol cat.)⁻¹ achieved in 2 hours of irradiation with visible (475 nm) light. This promising result provides a path forward in the...