weighted by cyclical constrains. Furthermore, the approach proposed by Schumpeter embodies another fundamental idea, which is the competition between innovators. Indeed, these players pursue the monopoly rents that accrue to new proprietary technologies, and, as such, intend to be the fi rst to fi nd the right solution to the right problem at the right moment. Economists have been studying the relationship between innovation and competition for many years, trying to understand more specifi cally whether competition fosters innovation or not. As a matter of fact, some concluded on a negative infl uence of competition upon innovation and some on a positive effect. [ 2,5 ] But it appears that many economists and marketers converge toward the idea that the innovation versus competition curve shows an inverted U shape. [ 6 ] In other words some competition is constructive, yet aggressive competition tends to hamper the innovation process.It is interesting to place in this context the concept of duplication. Historians and sociologist often refer to multiple discoveries for cases in which similar discoveries are made simultaneously by scientists working independently from each other. [ 7 ] The wide literature of scientifi c discovery can be classifi ed into three basic categories: [ 8 ] the genius model, [ 9 ] the model based on chance, [ 10 ] and the model relying on cultural maturation. [ 11 ] The latter type, which is the more prone to multiplicity, suggests that the contributions of individual researcher are epiphenomenal. This school of thought advocates the infl uence of social determinism and zeitgeist. [ 12 ] As a consequence, it proposes that the change in science is strongly infl uenced by cultural priorities and research programs. [ 8 ] This very type of duplication can be considered benefi cial for society as a higher number of independent experiments does maximize the probability of the accuracy and the reality of a given discovery. [ 11 ] This point of view is easily applicable to paradigm shifting, major discoveries, especially if they occurred before the era of easily accessible information via the internet, gigantic centralized databases, and ultrafast search engines. However, nowadays it may appear obvious that the replication of the effort to generate innovation is socially suboptimal and reduces the overall return on investment for entities that fi nance research. None of the studies mentioned above accounts for that phenomenon because of the diffi culty to quantify modern duplication. Thus, despite its acknowledged relevance [ 13 ] and occurrence, the share and infl uence of modern duplication in academic and industrial research remains largely underexplored. The European Patent Offi ce (EPO) affi rms that "up to 30% of all expenditure in R&D is wasted on redeveloping existing Copper sulfi des and copper selenides have recently been reported as new and promising low-cost and environmentally friendly thermoelectric materials. Here, it is shown that these materials have actually been studied for mo...

Aliphatic PNP pincer-supported earth-abundant manganese­(I) dicarbonyl complexes behave as effective catalysts for the acceptorless dehydrogenative coupling of a wide range of alcohols to esters under base-free conditions. The reaction proceeds under neat conditions, with modest catalyst loading and releasing only H2 as byproduct. Mechanistic aspects were addressed by synthesizing key species related to the catalytic cycle (characterized by X-ray structure determination, multinuclear (1H, 13C, 31P, 15N, 55Mn) NMR, infrared spectroscopy, inter alia), by studying elementary steps connected to the postulated mechanism, and by resorting to DFT calculations. As in the case of related ruthenium and iron PNP catalysts, the dehydrogenation results from cycling between the amido and amino-hydride forms of the PNP-Mn­(CO)2 scaffold. For the dehydrogenation of alcohols into aldehydes, our results suggest that the highest energy barrier corresponds to the hydrogen release from the amino-hydride form, although its value is close to that of the outer-sphere dehydrogenation of the alcohol into aldehyde. This contrasts with the ruthenium and iron catalytic systems, where dehydrogenation of the substrate into aldehyde is less energy-demanding compared to hydrogen release from the cooperative metal–ligand framework.