Hybrid Diamond-Metal Structures from Diamondoids: Synthesis and Catalytic Applications – HYBRIDIAMS

We have described the preparation of hybrid materials by innovative vapor deposition techniques and chemical methods inspired by the reactivity of transition metals. Progress has been made both in the preparation of new hybrid materials endowed with valuable physical properties allowing high catalytic activity and direct separability. It is, nevertheless, as gas sensors that nanodiamond materials have shown the most spectacular results.

Diamondoids, sp3-hybridized nanometer-sized diamond-like hydrocarbons (nanodiamonds), difunctionalized with hydroxy and primary phosphine oxide groups, enabled the assembly of the first sp3-C-based chemical sensors by vapor deposition. Both pristine nanodiamonds and palladium nanolayered composites can be used to detect toxic NO2 and NH3 gases. This carbon-based gas sensor technology allows reversible NO2 detection down to 50 ppb and NH3 detection at 25–100 ppm concentration with fast response and recovery processes at 100°C. Reversible gas adsorption and detection is compatible with 50% humidity conditions. Semiconducting p-type sensing properties are achieved from devices based on primary phosphine–diamantanol, in which high specific area (ca. 140 m2 g–1) and channel nanoporosity derive from H–bonding.
This work dedicated to a new paradigm in the formation of mild detection-conditions sensors was published in Angewandte Chemie International Edition.

Catalysts investigation were also conducted. We presented the Pd-catalyzed arylation of (N–H)-indoles with functionalized haloarenes “on water” using hitherto untested primary diamantyl phosphine oxides (PPO) as ligands. Remarkable C2–H arylation selectivity was achieved by employing functionalized iodoarenes and N-unprotected indoles. We provided evidence that the in situ generated oxide of (9-hydroxydiamant-4-yl)phosphine L1 is key for the reaction efficiency by comparing a set of diamantane-based compounds structurally related to L1. Our results demonstrated the power of the new PPO ligands for the C–H functionalization of unprotected (N–H)-heterocycles. This partly delivered our second objective [b]. However, our attempts for recycling were unsuccessful.

This led us to turn out towards new catalysts based on nanoparticles assembled in networks and stabilized by functionalized diamondoids (out of the scope of the present ANR program):

Nanocatalysts for High Selectivity Enyne Cyclization: Oxidative Surface Reorganization of Gold Sub-2-nm Nanoparticle Networks
H. Nasrallah, Y. Min, E. Lerayer, T.-A. Nguyen, D. Poinsot, J. Roger, S. Brande`s, O. Heintz, P. Roblin, F. Jolibois, R. Poteau, Y. Coppel, M. L. Kahn, I. C. Gerber,* M. R. Axet,* P. Serp,* and Jean-Cyrille Hierso*.
JACS Au (2021), 1, 187-200.

3D Ruthenium Nanoparticle Covalent Assemblies from Polymantane Ligands for Confined Catalysis. Min, Y.; Nasrallah, H.; Poinsot, D.; Lecante, P.; Tison, Y.; Martinez, H.; Roblin, P.; Falqui, A.; Poteau, R.; del Rosal, I.; Gerber, I.; Hierso, J.-C.*; Axet, R.*; Serp, P.* Chemistry of Materials (2020), 32, 2365–2378.

Porous Materials Based on 3-Dimensional Td-Directing Functionalized Adamantane Scaffolds and Applied as Recyclable Catalysts. Nasrallah, H.; Hierso, J.-C.*
Chemistry of Materials (2019), 31, 619-642.

1.Diamondoid Nanostructures as sp3-Carbon-Based Gas Sensors
Oana Moncea, Juan Casanova-Chafer, Didier Poinsot, Lukas Ochmann, Clève D. Mboyi, Houssein O. Nasrallah, Eduard Llobet,* Imen Makni, Molka El Atrous, Stéphane Brandès, Yoann Rousselin, Bruno Domenichini, Nicolas Nuns, Andrey A. Fokin, Peter R. Schreiner,* and Jean-Cyrille Hierso*
Angewandte Chemie, International Edition (2019), 58(29), 9933-9938.

2.Palladium-Catalyzed C2-H Arylation of Unprotected (N-H)-Indoles «On Water« Using Primary Diamantyl Phosphine Oxides as a Class of Primary Phosphine Oxide Ligands
Moncea, Oana; Poinsot, Didier; Fokin, Andrey A.; Schreiner, Peter R.; Hierso, Jean-Cyrille
ChemCatChem (2018), 10(13), 2915-2922.

3.Nanodiamond-Palladium Core-Shell Organohybrid Synthesis: A Mild Vapor-Phase Procedure Enabling Nanolayering Metal onto Functionalized sp3-Carbon
Maria A. Gunawan, Oana Moncea, Didier Poinsot, Mariem Keskes, Bruno Domenichini,
Olivier Heintz, Rémi Chassagnon, Frédéric Herbst, Robert M. K. Carlson, Jeremy E. P. Dahl, Andrey A. Fokin, Peter R. Schreiner,* and Jean-Cyrille Hierso*
Advanced Functional Materials (2018), 28, 1705786.

This research project aims at exploring the reactivity and exploiting the properties of
thermodynamically extremely stable, and highly regular, nm-sized carbon cages named diamondoids
(nanodiamonds) in connection with transition metal catalysis. We outline the preparation
of hybrid materials that combine pure sp3 carbon and transition metals into uniquely ordered
structures. Such novel hybrids are expected to display hitherto unreported physical and catalytic
properties due to the intimate connection of the metal-carbon moieties. The “bottom-up” synthesis
of diamond-like structures captures some of the highly desirable properties (structural integrity,
optical transparency, negative electron affinity etc.) of bulk diamond at the nanoscale. Ideally, this
approach could also be turned into growth of diamond-like films of controlled purity by innovative
vapor phase deposition techniques and chemical methods inspired by transition metal reactivity
(C–H activation and transition metal promoted C–C bond formation). We propose a combined
synthetic, physical, and computational approach, which brings together both fundamental
understanding as well as applications in organic synthesis and material sciences. Advances are
expected in the preparation of novel hybrid materials with exciting physical properties enabling high
catalyst activity and straightforward separability.

The ANR-DFG International Cooperative Research Call is an ideal framework to advance this
project because the French team of J.-C. Hierso (JCH) specializes in Transition Metal Chemistry
and Catalysis while the German group of P. R. Schreiner (PRS) focuses on Synthetic Organic and
Computational Chemistry. Additionally, both teams benefit from cooperations with several material
scientists working in the fields of nanosciences and vapor deposition (B. Domenichini group in
Dijon) with access to all the necessary facilities including high-resolution microscopies and Xray/
photoemission characterization of materials (Laboratory of Materials Science, LaMa, JLU
Giessen; PRS is a LaMa member). This consortium has started to jointly work in 2011 through a
50-50% co-tutelle PhD supervision (MSc Maria Gunawan; this program is also supported by the
Deutsch-Französische Hochschule / Université franco-allemande). Our collaboration has already
resulted in several joint publications in high-level international journals (vide infra). A second cotutelle
student (MSc Oana Moncea) has begun her work to continue this highly successful
collaboration.

The work proposed is considered frontier and explorative research since the main objective of
assembling robust metallized nanostructures starting from well defined and appropriately
functionalized nanodiamonds has never been tackled before. In addition, it also addresses the
ANR call descriptors “Axis 5-nanomaterials and nanotechnologies for products of the future” in the
subsection concerning “Objects production with novel properties and designed assemblies.”
The transdisciplinary methodology we propose opens exciting perspectives in nanosciences,
transition metal catalysis, and hybrid materials. This ANR-DFG program gives French and German
researchers the opportunity to further their scientific collaborations, and thereby hopes to give rise
to a European team of excellence. This binational innovative project clearly stands out from ongoing
national projects and is characterized by ideal complementarity between the teams of each
country and full integration of the work.