Publications by authors named "A Bulbena Cabre"

Alcohols are among the most abundant chemical feedstocks, yet they remain vastly underutilized as coupling partners in transition metal catalysis. Herein, we describe a copper metallaphotoredox manifold for the open shell deoxygenative coupling of alcohols with -nucleophiles to forge C()-N bonds, a linkage of high value in pharmaceutical agents that is challenging to access via conventional cross-coupling techniques. -heterocyclic carbene (NHC)-mediated conversion of alcohols into the corresponding alkyl radicals followed by copper-catalyzed C-N coupling renders this platform successful for a broad range of structurally unbiased alcohols and 18 classes of -nucleophiles.

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Ullmann-type C-N coupling reactions represent an important alternative to well-established Pd-catalyzed approaches due to the differing reactivity and the lower cost of Cu. While the design of anionic Cu ligands, particularly those by Ma, has enabled the coupling of various classes of aryl halides and alkyl amines, most methods require conditions that can limit their utility on complex substrates. Herein, we disclose the development of anionic ,-diarylbenzene-1,2-diamine ligands that promote the Cu-catalyzed amination of aryl bromides under mild conditions.

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Chiral compounds containing nitrogen heteroatoms are fundamental substances for the chemical, pharmaceutical and agrochemical industries. However, the preparation of some of these interesting scaffolds is still underdeveloped. Herein we present the synthesis of a family of P-stereogenic phosphinooxazoline iridium catalysts from L-threonine methyl ester and their use in the asymmetric hydrogenation of N-Boc-2,3-diarylallyl amines, achieving very high enantioselectivity.

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Chiral amines are key structural motifs present in a wide variety of natural products, drugs, and other biologically active compounds. During the past decade, significant advances have been made with respect to the enantioselective synthesis of chiral amines, many of them based on catalytic asymmetric hydrogenation (AH). The present review covers the use of AH in the synthesis of chiral amines bearing a stereogenic center either in the α, β, or γ position with respect to the nitrogen atom, reported from 2010 to 2020.

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The catalytic union of amides, sulfonamides, anilines, imines or -heterocycles with a broad spectrum of electronically and sterically diverse alkyl bromides has been achieved via a visible light-induced metallaphotoredox platform. The use of a halogen abstraction-radical capture (HARC) mechanism allows for room temperature coupling of C( )-bromides using simple Cu(II) salts, effectively bypassing the prohibitively high barriers typically associated with thermally-induced S2 or S1 -alkylation. This regio- and chemoselective protocol is compatible with >10 classes of medicinally-relevant -nucleophiles, including established pharmaceutical agents, in addition to structurally diverse primary, secondary and tertiary alkyl bromides.

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