https://hdl.handle.net/10259/3594 2026-04-17T17:33:35Z https://hdl.handle.net/10259/10507 Transition Metal-Free Synthesis of Halobenzo[b]furans from O-Aryl Carbamates via o-Lithiation Reactions Feberero García, Claudia; Virumbrales Ortiz, Cintia; Sedano Labrador, Carlos; Renedo Peña, Lorena; Suárez Pantiga, Samuel; Sanz Díez, Roberto A straightforward and transition metal-free one-pot protocol to synthesize halobenzo[b]furans has been developed employing simple and easily available starting materials such as O-aryl carbamates and alkynylsulfones. The fine-tuning of the different steps involved was key to achieving a successful one-pot procedure. Initially, a directed ortho-lithiation process, which uses the carbamate as the directed metalation group, was crucial in providing access to O-2-alkynylaryl N,N-diethyl carbamates by a direct alkynylation of the o-lithiated carbamate, with arylsulfonylalkynes as electrophilic reagents. Cyclization of the generated o-alkynylaryl carbamates was successfully accomplished through a strategy involving in situ carbamate alkaline hydrolysis under conventional heating or microwave irradiation, coupled with a subsequent heterocyclization step delivering the desired benzo[b]furans. A wide variety of new halobenzo[b]furans has been synthesized and their utility has been demonstrated by their further transformation. 2022-01-01T00:00:00Z https://hdl.handle.net/10259/10506 γ‐Terpinene: Biorenewable Reductant for the Molybdenum‐Catalyzed Reduction of Sulfoxides, N‐Oxides and Nitroarenes Hernández Ruiz, Raquel; Solas Luera, Marta; Suárez Pantiga, Samuel; Pedrosa Sáez, María de los Remedios; Sanz Díez, Roberto A molybdenum-catalyzed deoxygenation of sulfoxides, pyridine and quinoline N-oxides, N-hydroxybenzotriazoles, as well as the reduction of nitroarenes to anilines, has been developed using monocyclic terpenes such as γ-terpinene as an environmentally benign hydrogen surrogate. The only byproducts generated are water and p-cymene, under neat reaction conditions in which the terpene acts as both solvent and reducing agent. These features make this approach a highly attractive and sustainable alternative for the reduction of S-O and N-O containing compounds. Additionally, the reaction exhibited excellent chemoselectivity, tolerating a wide variety of functional groups. 2025-05-01T00:00:00Z https://hdl.handle.net/10259/10505 Molybdenum‐Catalyzed Direct Synthesis of Pyrroles from Nitroarenes with Glycols as Reductants Gómez Gil, Sara; Suárez Pantiga, Samuel; Pedrosa Sáez, María de los Remedios; Sanz Díez, Roberto A molybdenum-catalyzed synthesis of N-(hetero)aryl pyrroles directly from inexpensive and commonly available (hetero)nitroarenes via reduction with pinacol and annulation with 1,4-dicarbonyls or cyclobutane-1,2-diols has been described. The process does not require an inert atmosphere and tolerates the presence of air and water. This non-noble catalytic system shows high chemoselectivity, allowing a diverse range of potentially reducible functional groups such as alkynes, alkenes, halogens, cyano, and carbonyls. Moreover, this strategy enables the reuse of a waste byproduct as reactant, facilitating the formation of challenging 1,4-dicarbonyls from accessible cyclobutane-1,2-diols used as reducing agents. 2024-10-01T00:00:00Z https://hdl.handle.net/10259/10503 Halogen Promoted Desulfurative Cleavage of Cyclopropylmethyl Thioethers and Amination of the Formed Cyclopropylcarbinyl Cations Marín Díaz, Pablo; Martínez Núñez, Clara; Sanz Díez, Roberto; Suárez Pantiga, Samuel Cyclopropylmethyl sulfides react with N-fluorosulfonimide (NFSI) or molecular iodine, enabling C−S cleavage to generate cyclopropylcarbinyl cations, which evolve through cyclopropane ring-opening reactions into homoallyl cations suitable to react with nucleophiles present in the reaction media. This desulfurative cleavage of cyclopropylmethyl thioethers under non-acidic conditions facilitates homoallylation of N-based nucleophiles such as alkyl or aryl amines as well as sulfonimides through a one-pot protocol in one or two steps depending on the nucleophile. The reaction is initiated by a halogen-sulfur bond that causes C−S bond cleavage. Moreover, the reaction with iodine proceeds through homoallyl iodide intermediates. 2024-03-01T00:00:00Z