Christophe M. Thomas

Paris Sciences and Letters (PSL) University · Chimie ParisTech - CNRS, Institut de Recherche de Chimie Paris

We report here a unique example of an in situ generated aluminum initiator stabilized by a C2-symmetric salen ligand which shows a hitherto unknown high activity for the ROP of rac-lactide at room temperature. Using a simple and robust catalyst system, which is prepared from a salen complexe and an onium salt, this convenient route employs readily...

The vast majority of commodity materials are obtained from fossil fuels. However, many studies predict that all fossil resources will be depleted within a few centuries. Biomass represents an abundant carbon-neutral renewable resource for the production of materials. Using biomass for the production of new polymers can have both economic and enviro...

The carbonylation of methanol to give acetic acid is one of the most important homogeneously catalyzed industrial processes. The original [Rh(CO)2I2]− catalyst, developed at the Monsanto laboratories and studied in detail by Forster and co-workers, is largely used for the industrial production of acetic acid and anhydride. The conditions used (30–6...

The most versatile furanic building block for chemical and polymer applications is 2,5-furandicarboxylic acid. However, the classical 2,5-furandicarboxylic acid production methodology has been found to have significant drawbacks that hinder industrial-scale production. This review highlights new alternative methods to synthesize 2,5-furandicarboxyl...

The oligomerization of 1-hexene under argon plasma was investigated in a gas-liquid, continuous flow microreactor. The evolution of the yields of the reaction products as a function of the residence...

Finding catalysts that are both robust and highly active at room temperature can often be considered as a daunting challenge. Yet, these features are desirable for polymer synthesis as they allow to produce materials of interest easily and sustainably. Herein, commercial reagents are used to form in situ “ate” complexes which were found to be highl...

The design of new materials with tunable properties and intrinsic recyclability, derived from biomass under mild conditions, stands as a gold standard in polymer chemistry. Reported herein are platinum complexes which catalyze the formation of poly(silylether)s (PSEs) at low catalyst loadings. These polymers are directly obtained from dual-function...

The design of new materials with tunable properties and intrinsic recyclability, derived from biomass under mild conditions, stands as a gold standard in polymer chemistry. Reported herein are platinum complexes which catalyze the formation of poly(silylether)s (PSEs) at low catalyst loadings. These polymers are directly obtained from dual-function...

This review highlights recent developments in the field of biodegradable polymeric materials intended to replace non-degradable conventional plastics, focusing on studies from the last ten years involving the stereoselective ring-opening polymerization of cyclic esters. This encompasses exciting advances in both catalyst design and monomer scope. N...

Here we present a multicatalytic route to produce 2,5-bis(hydroxymethyl)furan and the corresponding (co)polymers from stable 2,5-furanedicarboxylic acid. This one-pot approach combines the use of several commercial catalysts and in particular...

Shifting from petrochemical feedstocks to renewable resources can address some of the environmental issues associated with petrochemical extraction and make plastics production sustainable. Therefore, there is a growing interest in selective methods for transforming abundant renewable feedstocks into monomers suitable for polymer production. Report...

Shifting from petrochemical feedstocks to renewable resources can address some of the environmental issues associated with petrochemical extraction and make plastics production sustainable. Therefore, there is a growing interest in selective methods for transforming abundant renewable feedstocks into monomers suitable for polymer production. Report...

To prepare biobased polymers, particular attention must be paid to the obtention of the monomers from which they are derived. (Meth)acrylates and their analogs constitute such a class of monomers that have been extensively studied due to the wide range of polymers accessible from them. This review therefore aims to highlight the progresses made in...

Over the past decade, on-surface fabrication of organic nanostructures has been widely investigated for the development of molecular electronic components, catalysts, and new materials. Here, we introduce a new strategy to obtain alkyl oligomers in a controlled manner using on-surface radical oligomerisations that are triggered by electrons between...

Ru(II) polypyridyl complexes are compounds of great interest in cancer therapy due to their unique photophysical, photochemical, and biological properties. For effective treatment, they must be able to penetrate tumor cells effectively and selectively. The development of nanoscale carriers capable of delivering Ru(II) polypyridyl complexes has the...

Antimicrobial photodynamic therapy (aPDT) also known as photodynamic inactivation (PDI) is a promising strategy to eradicate pathogenic microorganisms such as Gram-positive and Gram-negative bacteria. This therapy relies on the use of a molecule called photosensitizer capable of generating, from molecular oxygen, reactive oxygen species including s...

BiCuOS is a non‐toxic p‐type semiconductor which could be a promising candidate for photoelectric applications. However, like most chalcogenide‐based materials, it shows poor chemical stability during the thermal treatment necessary to enhance transport properties through sintering processes. Solutions must be found to obtain thin films with a good...

Ruthenium complexes have attracted a lot of attention as potential photosensitizers (PSs) for photodynamic therapy (PDT). However, some of these PSs are unsuitable for PDT applications due to their low cellular uptake, which is possibly the consequence of their relatively low degree of lipophilicity, which prevents them from penetrating into tumor...

The epoxidation of allylic alcohols with H2O2 catalyzed by the hybrid [α-B-SbW9O33(tBuSiO)3Ti(OiPr)]3- (1) anion as molec-ular model of heterogeneous Ti-silicalite TS-1 catalyst was analyzed by means of DFT to determine the main factors that control the catalytic process and, finally, to improve the value of the available catalysts. Our calculation...

Ruthenium complexes, and especially ruthenium(II) polypyridyl complexes, have attracted a lot of attention as potential photosensitizers for photodynamic therapy. However, some are unsuitable due to their low cellular uptake, potentially due to their relatively low degree of lipophilicity, which prevents them from penetrating tumor cells. Here, we...

Novel zinc(II) and cobalt(II) complexes containing tripodal mono(phenolate) ligands have been synthesized and characterized. The resulting mononuclear complexes act as efficient initiators in the polymerization of rac-lactide to provide the corresponding biodegradable poly(lactic acid). Most of these polymerizations proceeded in a controlled fashio...

An effective route for ring-opening copolymerization of β-butyrolactone (BBL) with ε-decalactone (ε-DL) is reported. Microstructures of the block copolymers characterized by 13C NMR spectroscopy revealed syndiotactic-enriched poly(3-hydroxybutyrate) (PHB) blocks. Several di- and triblock copolymers (PDL-b-PHB and PDL-b-PHB-b-PDL, respectively) were...

We report here the synthesis and grafting of easily accessible catechol-terminated poly(3-hexylthiophenes) onto Al-doped ZnO particles (ZnO:Al) to obtain a performance-improved polycrystalline assembly. These macromolecular binding species favor electronic conduction from one grain to another. Resistivity measurements of the grafted ZnO:Al powders...

Polypeptides are a class of important biomaterials that are extensively utilized in applications such as drug delivery systems, sensors, tissue engineering, biomimetic synthesis of ordered inorganic nanostructures, and catalysis. In particular, the association of polypeptides to polyesters in copolymer architectures provides versatile original mate...

Enantiopure poly(lactic acid) (PLA) can form stereocomplexes when enantiomeric PLA chains are mixed in equivalent amounts. Such materials provide interesting features that might be suitable for numerous applications. Despite several advantages, the main drawback of PLA is its narrow window of processing, thus limiting its use for industrial applica...

Enantiopure poly(lactic acid) (PLA) can form stereocomplexes when enantiomeric PLA chains are mixed in equivalent amounts. Such materials provide interesting features that might be suitable for numerous applications. Despite several advantages, the main drawback of PLA is its narrow window of processing, thus limiting its use for industrial applica...

Some Ru complexes have extremely promising anticancer or antibacterial properties, but the poor H 2 O solubility and/or low stability of many Ru complexes in aqueous solution under physiological conditions and/or metabolic or biodistribution profiles prevent their therapeutic use. To overcome these drawbacks, various strategies have been developed...

Chemical Biology is the science of designing chemical tools to dissect and manipulate biology at different scales. It provides the fertile ground from which to address important problems of our society, such as human health and environment.

Bio-based polyesters attract a lot of interest with regard to sustainable development as alternatives to polymers derived from oil. Aliphatic polyesters are biodegradable and frequently biocompatible. Thanks to these properties, they have numerous applications in daily life such as packaging but also in niche markets (biomedical devices). Ring-open...

Over the past decade, on-surface fabrication of organic nanostructures has been widely investigated for the development of molecular electronic devices, nanomachines, and new materials. Here, we introduce a new strategy to obtain alkyl oligomers in a controlled manner using on-surface radical oligomerisations that are triggered by the electrons/hol...

Biobased diepoxy synthons derived from isoeugenol, eugenol or resorcinol (DGE-isoEu, DGE-Eu and DGER, respectively) have been used as epoxy monomers in replacement of the diglycidyl ether of bisphenol A (DGEBA). Their curing with six different biobased anhydride hardeners leads to fully biobased epoxy thermosets. These materials exhibit interesting...

The enantiomeric state of a supramolecular copper catalyst can be switched in situ in ca. five seconds. The dynamic property of the catalyst is provided by the non-covalent nature of the helical assemblies supporting the copper centres. These assemblies are formed by mixing an achiral benzene-1,3,5-tricarboxamide (BTA) phosphine ligand (for copper...

The enantiomeric state of a supramolecular copper catalyst can be switched in situ in ca. five seconds. The dynamic property of the catalyst is provided by the non-covalent nature of the helical assemblies supporting the copper centres. These assemblies are formed by mixing an achiral benzene-1,3,5-tricarboxamide (BTA) phosphine ligand (for copper...

Correction for ‘Transition from smectic nanofibers to smectic vesicles in the self-assemblies of PEG- b -liquid crystal polycarbonates’ by Lu Zhou, et al. , Polym. Chem. , 2017, DOI: 10.1039/c7py01131h.

This work reports on the self-assemblies of novel amphiphilic biodegradable cholesterol-containing block copolymers PEG-b-PMCC. The polymers are prepared through the ring opening polymerization (ROP) of a methyl and cholesteryl substituted...

An effective preparation of new tailor-made macromolecular materials via a combination of two (atom-efficient) catalytic transformations is reported. First, new aliphatic polyesters with alternated composition have been prepared using a salen aluminum catalyst system. Next, the pendant vinyl moieties in those copolymers have been selectively transf...

A plasma microreactor dedicated to chemical synthesis has been conceived and developed using soft-lithography techniques. In this study, we propose to use highly reactive species created by the plasma discharge to replace traditionally used chemical initiators. A dielectric barrier discharge plasma was generated under atmospheric pressure and then...

A series of polylactides was prepared by stereoselective ring-opening polymerization of rac-lactide.

A new tandem catalytic system mediates very efficiently and selectively at room temperature two sequential reactions to produce relevant derivatives in one pot. Remarkably, this new concept of catalysis allows the facile synthesis of polypeptides and provides direct access to cyclic carbonates in high yields, through the incorporation of the carbon...

In order to obtain alternating/stereocontrolled polymers, coordination polymerization using well-defined metal complexes has played a leading role in the last two decades. We have described selected published efforts to achieve these research goals using discrete, structurally well-characterized metal complexes.

An efficient, high-yielding sustainable route to cyclic anhydrides from biorenewable and inexpensive dicarboxylic acids has been developed. Cyclic anhydrides were synthesized from dicarboxylic acids using a catalyst prepared in situ from MgCl2 and dialkyl dicarbonates. This robust and cheap system operates under mild conditions to give cyclic anhyd...

The coordination chemistry of a series of pro-ligands ([]-[]) with cobalt and zinc derivatives has been studied. All complexes have been characterized by multinuclear NMR, elemental analysis, and by single-crystal X-ray diffraction studies. Polymerization of rac-lactide takes place at 130 °C in the presence of cobalt and zinc complexes to yield pol...

Most germane: Hexacoordinate germanium(IV) species exhibit unprecedented activities, yet controlled behavior, as initiators for the ring-opening polymerization of rac-lactide to form polylactide polymers.

The creation of polymers by tandem catalysis represents an exciting frontier in materials science. Tandem catalysis is one of the strategies used by Nature for building macromolecules. Living organisms generally synthesize macromolecules by in vivo enzyme-catalyzed chain growth polymerization reactions using activated monomers that have been formed...

The ring-opening polymerization of beta-butyrolactone and lactide in solvent-free conditions and using NHC carboxylates as a (pre)catalyst is described. This class of catalysts enables the synthesis of aliphatic polyesters. These organocatalysts, which are easily synthesized, are remarkably robust, thus allowing the use of a bench-top reaction setu...

A joint experimental/theoretical study has been carried out on the putative MMA polymerization catalyzed by an yttrium isopropyloxide complex. Despite its high activity in lactone polymerization, this catalyst is found to be unreactive on methyl methacrylate (MMA) polymerization. This surprising result is rationalized using a computational approach...

In this review, attention is focused on the use of group 3 metal complexes for the ring-opening polymerization (ROP) of lactide to give polylactides (PLAs). Synthesis of PLAs has been studied intensively due to their biocompatible and biodegradable properties and their potential applications in medical and agricultural fields. ROP of lactide, a cyc...

Synthesis of aliphatic polyesters has been studied intensively due to their biocompatible and biodegradable properties and their applications in medical and agricultural fields. Among them, polyhydroxybutyrate (PHB), which is a naturally occurring polymer, is synthesized by a variety of bacteria and algae. However, this polymer has poor mechanical...

The polymerization of MMA by a supported neodymium borohydride catalyst proceeds with moderate tendency toward isoselectivity, whereas the molecular precursor generates a syndiotactic-rich polymer. DFT studies reveal that initiation proceeds via borohydride attack on the first coordinated monomer followed by BH3 trapping by the silica surface. The...

Supplementary Figures S1-S28

The vast majority of commodity materials are obtained from petrochemical feedstocks. These resources will plausibly be depleted within the next 100 years, and the peak in global oil production is estimated to occur within the next few decades. In this regard, biomass represents an abundant carbon-neutral renewable resource for the production of pol...

Das Geheimnis liegt in der Sequenz: Die Primärstruktur von Poly(lactid-co-glycolid) (PLGA), einem Vertreter der meistgenutzten Klasse bioabbaubarer Polymere für biomedizinische Anwendungen, hat großen Einfluss auf die Abbaueigenschaften des Polymers. Experimentelle Studien zeigen den positiven Einfluss geordneter Monomersequenzen auf die Materialei...

Its all in the sequence: The primary structure of poly(lactic-co-glycolic acid) (PLGA), a member of the most widely used class of biodegradable polymers employed in biomedical applications, is demonstrated to strongly influence its degradation properties. Experimental studies evidenced the beneficial effect of ordered monomer sequences on the mater...

Novel gold(I) complexes containing N-heterocyclic carbene ligands have been synthesized and fully characterized. The resulting mononuclear gold complexes act as active initiators in the polymerization of rac-β-butyrolactone under solvent-free conditions to provide the corresponding biodegradable poly(3-hydroxybutyrate).

A systematic study on the encapsulation and drug release efficiency of L-leuprolide acetate (LeA) with a series of different functionalized poly(β-hydroxyalkanoate)s (PHAs) is reported. Significant differences on the in vitro release kinetics of LeA, depending essentially on the microstructure, chemical functionality, and molecular weights of polym...

A series of methoxy-amino-bis(phenol)s (ONOO(R(1),R(2)))H(2) possessing on the phenol rings R(1) ortho substituents with variable steric and electronic properties (R(1)=CMe(2)Ph, 1; CMe(2)tBu, 3; CMe(2)(4-CF(3)C(6)H(4)), 5; CPh(3), 9; Cl, 10) has been synthesized and further reacted with [Y{N(SiHMe(2))(2)}(3)](THF)(2) to give cleanly the correspond...

The creation of polymers with a high degree of sequence and/or stereocontrol represents an exciting frontier in materials science. In order to obtain alternating polymers, coordination polymerization using well-defined metal complexes has played a leading role in the last two decades. In the following paper, we will describe selected published effo...

A series of hybrid materials, bearing neodymium silylamide initiating groups, have been shown to mediate isoprene polymerization when combined with alkyl aluminum activators [methylaluminoxane, AlEt2Cl, Al(iBu) 3]. The surface species nature and relative distribution were correlated with isoprene polymerization activity and selectivity. This approa...

The traditional homogeneous access to aromatic amine derivatives is a nucleophilic aromatic substitution of the corresponding aryl halides. The halogen atom is usually relatively inert to amination reaction unless it is activated by the presence of electron withdrawing groups. Consequently, there has been particular emphasis over the past decade on...