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In the presence of Shvo's catalyst [2,3,4,5‐tetraphenyl‐1,3‐cyclopentadien‐1‐ol, ruthenium(II) complex], a small quantity of aniline and TGPS‐750‐M surfactant, terminal alkynes were hydrated under microwave (MW) dielectric heating in water as solvent with high conversion and good yield. The reaction gives the Markovnikov product exclusively, unlike that commonly observed with ruthenium complexes. Under the influence of MWs, Ru nanoparticles embedded in the nanomicelle environment were formed, acting as the effective hydration catalyst. Introducing sodium formate in the aqueous phase and using a stoichiometric amount of amines, the Ru nanoparticle nanomicelle catalyst gave the first example of one‐pot single‐step hydroamination of alkynes with the formation of the corresponding secondary amines. The reaction is characterized by low environmental impact as TGPS‐750‐M is required in low amount, and organic solvents employed only for product separation or catalyst recycling. [ABSTRACT FROM AUTHOR]

A simple and environmentally benign procedure for the synthesis of secondary amines in water has been developed. Combining Ru3(CO)12, tetraphenylcyclopentadienone and a small quantity of TGPS-750-M surfactant, primary and secondary alcohols were alkylated at N employing equimolar amounts of aromatic amines in water. The reaction occurs under microwave (MW) dielectric heating with high conversion and high yield. When required, the use of biomass-derived 2-MeTHF or GVL as a co-solvent is possible. Under the influence of MWs, a Ru nanoparticle–nanomicelle combination was formed acting as an effective and recyclable catalyst. This protocol was also employed for "in water" cyclisation to synthesise biologically relevant pyrrolobenzodiazepines (PBDs). [ABSTRACT FROM AUTHOR]

Starting from 2-aminobenzyl alcohols and 1,2-amino alcohols, 2,3,4,5-tetrahydro-1 H-1,4-benzodiazepines (TH-BDZ) can be prepared through a one-pot ruthenium-catalyzed reaction encompassing two consecutive borrowing hydrogen cycles. First, benzyl alcohol oxidation, condensation with the amino alcohol, and imine reduction occurs. This is followed by oxidation of the other alcohol functionality and reductive cyclocondensation to give the TH-BDZ derivatives. A single catalyst does the entire job, with two molecules of water being the only waste product. Many new substituted 2,3,4,5-tetrahydro-1 H-1,4-benzodiazepines have been prepared to demonstrate the versatility of this method, which can be used for the preparation of privileged scaffolds for drug discovery. [ABSTRACT FROM AUTHOR]

Cover Feature: In water Markovnikov hydration and one-pot reductive hydroamination of terminal alkynes under Ruthenium nanoparticle catalysis (Eur. J. Inorg. The reagents and the Ru catalyst are assembled within nanomicelles that release the final product into the water. The reagents and the Ru catalyst are assembled within nanomicelles that release the final product into the water. [Extracted from the article]