The underexploited biorenewable p-cymene is employed as a solvent for the metathesis of various substrates. p-Cymene is a nontoxic compound that can be obtained in large amounts as a side product of the cellulose and citrus industry. For the cross-metathesis of estragole with methyl acrylate, this solvent prevents the consecutive double-bond isomerization of the product and affords the best yield of all solvents tested. Undesired consecutive isomerization is a major challenge for many substrates in olefin metathesis, including pharmaceutical precursors, and the use of p-cymene as a solvent may be a way to prevent it. This solvent results in a better metathesis performance than toluene for the three substrates tested in this work, matching its performance for two other substrates.

The rhodium-catalyzed hydroformylation of 1-arylbutadienes derived from lignocellulosic bio-resources has been carried out in toluene and green solvents. In the presence of DPPE and XANTPHOS ligands, a regioselective Markovnikov Rh-H insertion takes place resulting in branched aldehydes in high selectivity, which contrasts with previous results obtained from aliphatic conjugated dienes. Depending on the nature of the diphosphine ligand, conjugated enals or saturated aldehydes are obtained in good to excellent selectivity. The later have a potential interest for fragrance industry, as they are homologous to commercial fragrance ingredients.

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Hydroformylation is a consolidated synthetic tool in the chemical industry, both in the commodity and in the fine chemicals segments. Olefin metathesis has been largely employed in the petrochemical sector,...

2-Arylpropylamines are useful as active pharmaceutical ingredients (APIs) and as synthetic building blocks in fine chemistry. Herein we report a new and efficient methodology to transform naturally occurring 1-propenylbenzenes into 2-arylpropylamines employing a one-pot ethenolysis/hydroaminomethylation protocol. Four consecutive reactions must occur in the same reaction vessel and the careful selection of the reaction conditions was critical to obtain the desired products in high yields. The negative interference between the ethenolysis and the hydroaminomethylation (HAM) catalysts was circumvented by the appropriate adjustment on the molar ratio of the catalysts. As a result, nine 2-arylpropylamines were obtained in yields ranging in 75-93 %.