An efficient conversion of biorenewable ferulic acid into bio‐catechol has been developed. The transformation comprises two consecutive defunctionalizations of the substrate, that is, C−O (demethylation) and C−C (de‐2‐carboxyvinylation) bond cleavage, occurring in one step. The process only requires heating of ferulic acid with HCl (or H2SO4) as catalyst in pressurized hot water (250 °C, 50 bar N2). The versatility is shown on a variety of other (biorenewable) substrates yielding up to 84 % di‐ (catechol, resorcinol, hydroquinone) and trihydroxybenzenes (pyrogallol, hydroxyquinol), in most cases just requiring simple extraction as work‐up.

A green, efficient and cheap demethylation reaction of aromatic methyl ethers with mineral acid (HCl or H2SO4) as catalyst in high temperature pressurized water provided the corresponding aromatic alcohols (phenols,...

An efficient conversion of biorenewable ferulic acid into bio-catechol has been developed. The transformation comprises two consecutive defunctionalizations of the substrate,t hat is,C ÀO( demethylation) and CÀC( de-2-carboxyvinylation) bond cleavage,occurring in one step.The process only requires heating of ferulic acid with HCl (or H 2 SO 4 )a s catalyst in pressurized hot water (250 8 8C, 50 bar N 2 ). The versatility is shown on av ariety of other (biorenewable) substrates yielding up to 84 %di-(catechol, resorcinol, hydroquinone) and trihydroxybenzenes (pyrogallol, hydroxyquinol), in most cases just requiring simple extraction as work-up.

An efficient strategy for the cleavage of the picolinamide directing group (DG) and recycling of the byproduct generated has been developed. In this protocol, picolinamides were first Boc activated into tertiary N-Boc-N-substituted picolinamides. These were then cleaved via a Ni-catalyzed esterification reaction with EtOH to give valuable N-Boc protected amines. Ni­(cod)2 was used as a catalyst without any ligands or base additives. The byproduct, ethyl 2-picolinate can be used to install the picolinamide DG in a direct or indirect manner on amines. The protocol exhibits a broad functional group tolerance and high yields. To demonstrate the utility of this approach, it was applied on many selected examples from the recent C–H functionalization literature featuring 2-picolinamide as a DG.

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Mineral acids in hot pressurized water are able to dealkylate aromatic biorefinery products, as described by B. U. W. Maes et al. in their Communication on page 3063. Ferulic acid obtained from rice bran, an agro‐industry waste product, can be transformed into bio‐catechol. Petrochemical catechol finds applications in the production of agrochemicals, pharmaceuticals, flavors, fragrances, and polymers, thereby serving modern society. Cover design by Joris Snaet.

Mineralsäuren in heißem Wasser unter Druck können aromatische Bioraffinerieprodukte desalkylieren, wie B. U. W. Maes et al. in ihrer Zuschrift auf S. 3087 schildern. Ferulinsäure aus Reiskleie, ein Abfallprodukt der Agrarindustrie, kann in Biocatechol überführt werden. Petrochemisches Catechol findet Anwendung bei der Produktion von Agrochemikalien, Pharmazeutika, Geschmacksstoffen, Duftstoffen und Polymeren und ist somit von großer Bedeutung für die moderne Gesellschaft. Cover: Joris Snaet.

1‐Thioxo‐tetrahydroisochinolin (I) wird mit Bromcyanessigsäureester (II) zum Cyan‐ethoxy‐carbonylmethylen‐tetrahydroisochinolin (III) umgesetzt, das mit Lithiumchlorid beim Erhitzen zu (IV) deethoxycarbonyliert.