Call, Arnau

Light-driven Stereoselective C-H amination and multivariate linear regression analysis

Contact info:
Dr. Arnau Call
Tel. (+34) 676 23 44 83


Selected publications

Arnau Call,* Giorgio Capocasa, Andrea Palone, Laia Vicens, Eric Aparicio, Najoua Choukairi Afailal, Nikos Siakavaras, Maria Euge?nia López Saló, Massimo Bietti,* Miquel Costas*
Highly Enantioselective Catalytic Lactonization at Nonactivated Primary and Secondary ??C?H Bonds
J. Am. Chem. Soc. 2023, 145, 18094?18103
DOI: 10.1021/jacs.3c06231

Arnau Call, Marco Cianfanelli, Pau-Besalú-Sala, Giorgio Olivo, Andrea Palone, Laia Vicens, Xavi Ribas, Josep M. Luis,* Massimo Bietti,* Miquel Costas*
Carboxylic Acid Directed ?-Lactonization of Unactivated Primary C-H Bonds Catalyzed by Mn Complexes. Application to Stereoselective Natural Products Diversification
J. Am. Chem. Soc. 2022, 144, 19542-19558
DOI: 10.1021/jacs.2c08620
Featured in Org. Chem. Highlights

Xian Zhang, Mihaela Cibian,* Arnau Call,* Kosei Yamauchi, Ken Sakai*
Photochemical CO2 Reduction Driven by Water-Soluble Copper(I) Photosensitizer with the Catalysis Accelerated by Multi-Electron Chargeable Cobalt Porphyrin
ACS Catal. 2019, 9, 11263?11273
DOI: 10.1021/acscatal.9b04023

Arnau Call,* Mihaela Cibian,* Keiya Yamamoto, Takashi Nakazono, Kosei Yamauchi, Ken Sakai*
Highly Efficient and Selective Photocatalytic CO2 Reduction to CO in Water by a Cobalt Porphyrin Molecular Catalyst
ACS Catal. 2019, 9, 4867?4874
DOI: 10.1021/acscatal.8b04975

Arnau Call, Carla Casadevall, Adrian Romero-Rivera, Vlad Martin-Diaconescu, Dayn J. Sommer, Sílvia Osuna, Giovanna Ghirlanda,* Julio Lloret-Fillol*
Improved Electro- and Photocatalytic Water Reduction by Confined Cobalt Catalysts in Streptavidin
ACS Catal. 2019, 9, 5837?5846
DOI: 10.1021/acscatal.8b04981

+ Publications

Dr. Arnau Call

Arnau Call (1989, Vidreres) obtained his Bachelor’s degree in Chemistry at the Universitat de Girona (UdG) in 2011 receiving the excellence award for academic performance. After that, he coursed the Master’s in Homogenous Catalysis (2012) and PhD (2016) with the FPU graduate fellowship under the supervision of Prof. Julio Lloret. Research work during his PhD involved a 3-month internship at Arizona State University (USA) in the group of Prof. Ghirlanda to develop artificial metalloenzymes. He also performed a 2 years stay at the Institut Català d’Investigació Química (ICIQ) when his supervisor became a group leader at this research center. Arnau also participated in detecting catalytic intermediates at the Diamond Light Source Synchrotron (UK). His PhD project was mainly directed to the development of molecular systems for H2 evolution and for the reduction of organic functionalities using light and water as a source of hydrides. During his PhD he established fruitful collaborations with Prof. Mas-Ballesté and Prof. Pérez-Prieto.
After defending his PhD in December 2016, he moved to the group of Prof. Sakai, at the International Institute for Carbon-Neutral Energy Research (Japan), where he focused on developing photocatalytic systems for CO2 reduction. In January 2021 he returned to the UdG in the group of Prof. Costas as “Juan de la Cierva” research fellow. He has recently performed a 4-month internship at the University of Utah (USA) in the group of Prof. Sigman to implement multivariate linear regression analysis in asymmetric C-H oxidation reactions.
In 2023 he started his independent career in the Universitat de Girona as “Ramon y Cajal” (RyC) researcher. His research interests involve the generation of metal nitrenoid species using light, and their application in the stereoselective amination of C-H bonds. Dr. Call also forms part of the QBIS-CAT group and actively participates in several projects focused on the asymmetric oxidation of C-H bonds.

Research overview

Nitrene C-H insertion reaction mediated by metal nitrenoid species has emerged as an attractive approach to selectively introduce amino groups. The traditional method for generating such species often relies on the use of nitrene precursors such as organic azides, iminoiodinanes, and dioxazolones, in which elevated temperatures are often required for nitrene generation. The use of high temperatures limits substrate scope and product selectivity.
Photochemical generation of nitrene species offers a potential solution to this issue. While free nitrenes efficiently react with organic compounds, the site-selectivity is mainly dictated and limited by the innate reactivity of the different C-H bonds in the substrate, and the reactions often produce product mixtures. As metal nitrenoid species are envisioned to display higher selectivity than free nitrenes, C-H amination driven by photogenerated metal nitrenoid species is envisioned to allow a control in the selectivity.
Our research project focusses on the development of new methods for generating well-defined metal nitrenoid species under visible light, capable of inducing (stereo)selectivity in C-H amination reactions.


Principal Investigator

Arnau Call

Full Professor

Staff and Postdocs

PhD and MACMoM students

Eric Aparicio

PhD Student

- M. Costas

Nikolaos Siakavaras

PhD student (IF-UdG)

- M. Costas
- A. Call


Juan de la Cierva

Project: Juan de la Cierva – Incorporación
Researcher: Dr. Arnau Call
Reference: IJC2020-046115-I
Funding: 93.000 €
Period: 01/01/2022 – 31/12/2024

MICIU Project

Project: Polímeros reciclables basados en lactonas bicíclicas híbridas preparadas mediante oxidación selectiva de enlaces sp3 C-H
Researcher: Dr. Miquel Costas and Dr. Arnau Call
Reference: TED2021-132648B-100
Funding: 287.500 €
Period: 01/12/2022 – 30/11/2024
Project: Catalizadores moleculares bioinspirados para la funcionalización estereoselectiva de enlaces sp2 y sp3 C-H
Researcher: Dr. Miquel Costas and Dr. Arnau Call
Reference: PID2021-129036NB-100
Funding: 326.700 €
Period: 01/09/2022 – 31/08/2025

Ramón y Cajal

Project: Programa Ramón y Cajal
Researcher: Dr. Arnau Call
Reference: RYC2022-038031-I
Funding: 324.250 €
Period: 2025 – 2029


Burkhard KönigUniversität Regensburg (Germany), collaboration with Arnau Call.
Alexandros ZografosAristotle University of Thessaloniki (Greece), collaboration with Arnau Call.
Massimo BiettiUniversity if Rome Tor Vergata (Italia), collaboration with Arnau Call.
Miquel CostasUniversiat de Girona (Spain), collaboration with Arnau Call.
Julio LloretInstitut Català d’Investigació Química (Spain), collaboration with Arnau Call.
Matthew SigmanUniversity of Utah (United States), collaboration with Arnau Call.