Transformations of bridging ligands in diiron complexes: unconventional routes to new functionalized multisite bound organic frames

The main scope of this Ph.D. thesis has concerned the possible transformations of bridging ligands in diiron complexes, in order to explore unconventional routes to the synthesis of new functionalized multisite bound organic frames. The results achieved during the Ph.D. can be summarized in the following points: 1) We have extended the assembling between small unsaturated molecules and bridging carbyne ligands in diiron complexes to other species. In particular, we have investigated the coupling between olefins and thiocarbyne, leading to the synthesis of thioallylidene bridging diiron complexes. Then, we have extended the study to the coupling between olefins and aminocarbyne. This result shows that the coupling between activated olefins and heteroatom substituted bridging carbynes has a general character. 2) As we have shown, the coupling of bridging alkylidyne ligands with alkynes and alkenes provides excellent routes to the synthesis of bridging C3 hydrocarbyl ligands. As a possible extension of these results we have examined the synthesis of C4 bridging frames through the combination of bridging alkylidynes with allenes. Also in this case the reaction has a general character. 3) Diiron complexes bearing bridging functionalized C3 organic frames display the presence of donor atoms, such as N and S, potentially able to coordinate unsaturated metal fragments. Thus, we have studied the possibility for these systems to act as ‘organometallic ligands’, in particular towards Pd and Rh. 4) The possibility of releasing the organic frame from the bridging coordination appears particularly appealing in the direction of a metal-assisted organic synthesis. Within this field, we have investigated the possibility of involving the C3 bridging ligand in cycloaddition reactions with alkynes, with the aim of generating variously functionalized five-membered cycles. The [3+2] cyclization does not lead to the complete release of the organic fragment but rather it produces its transformation into a cyclopentadienyl ring, which remains coordinated to one Fe atom. This result introduces a new approach to the formation of polyfunctionalised ferrocenes. 5) Furthermore, I have spent a research period of about six months at the Department of Inorganic Chemistry of the Barcelona University, under the supervision of Prof. Concepción López, with the aim of studying the chemistry of polydentate ferrocenyl ligands and their use in organometallic synthesis.

Bridging innovation, nature and tradition: assessment of strategies for rural tourism development in Maramureş (Romania)

In the frame of EU rural policy, always more oriented towards environmental concerns and green livelihoods, Romania stands out for the predominance of rural areas and high nature value farming. The country has to face the challenge of joining the modernization process of rural farming systems with the valorization of local assets. Tourism has emerged as one of the main drivers of change and contributors for a sustainable exploitation of local resources. Rural tourism (RT) can foster the enhancement of the territorial capital (TC), the preservation of public goods (PGs) and the promotion of a more environmental oriented livelihood. The research focuses on a case study area, two valleys from Maramureş, where environmental approaches as diversification strategies are partially explored. The work investigates the role of tourism initiatives for the promotion of green oriented practices. The first part of the work is based on a literature review and interdisciplinary analysis of secondary data to identify the key issues: from rural development policy, to the concept of TC, of PGs and RT. The Romanian development programmes and related strategies are investigated; afterwards the characteristics of the County and the role of RT as diversification and valorisation policies is considered. The second part is based on the collection of primary data through interviews to different local stakeholders (farmers owners of rural guesthouses, local administrators, networks and artisans). The main frequencies are analyzed, a cluster analysis is computed to evaluate the similarities within the most representative groups and a comparative analysis is carried out between the two Valleys. The frame of the analysis is based on a set of indicators following the dimensions of the TC, to assess the characteristics of the local stakeholders and to outline the perception about the local PGs and on the adopted strategies to manage the territory. Final considerations are elaborated and few scenarios are outlined, giving relevance to the importance of improving awareness and creating embeddedness among public-private local stakeholders and resources as a tool for a socio-economic and environmental development of the area.