A high-loading Ga-exchanged MFI zeolite was developed for efficient ethane dehydrogenation. Its high catalytic performance is ascribed to both the low amount of Brønsted acid sites and major formation [GaH 2 ] + ions among isolated Ga hydrides.

Carboxylic acids are Brønsted-Lowry acids, they are proton donors. They are the most common type of organic acid. Among the simplest examples are the formic acid H-COOH, that occurs in ants, and acetic acid H3C-COOH group, that gives vinegar its sour taste. Acids with two or more carboxyl groups are called dicarboxylic, tricarboxylic, etc. The simplest dicarboxylic example is oxalic acid (COOH)...

A fluorosulfoxonium cation and triflic acid were shown to promote ( n + 2) annulations of donor–acceptor cyclopropanes or -butanes with 1,2-dipoles, different activity selectivity but a presumed similar role as (hidden) Brønsted acids.

The selective transformation of hexose and pentose sugars to intermediate platform chemicals, such as furans, is an essential step in the conversion of cellulosic and hemicellulosic biomass to biofuels and biochemicals. Yet, many challenges in achieving commercially viable processes remain. In this feature article, we outline challenges that need to be overcome to enable these transformations. ...

The surface of SBA-15 was modified by diphenylphosphine; then, it was treated with butane sultone and sulfuric acid to obtain Brønsted acid HO3S-phosphonium based ionic liquid functionalized SBA-15 with HSO4- as a counteranion. It efficiently catalyzed synthesis of pyrano[3,2-c]chromenone derivatives through the reaction of 4-hydroxycoumarin and chalcones at...

One-dimensional γ-Al2O3 nanofibers were modified with Nb2O5 to be used as an efficient heterogeneous catalyst to catalyze biomass into 5-hydroxymethylfurfural (5-HMF). At low Nb2O5 loading, the niobia species were well dispersed on γ-Al2O3 nanofiber through Nb-O-Al bridge bonds. The interaction between Nb2O5 precursor and γ-Al2O3 nanofiber results in the niobia species with strong Lewis acid si...

Abyssomicin C is a recently discovered antibiotic with promising antibacterial activity, high structural complexity, and a novel mechanism of action. We give an account of our abyssomicin campaign and some of the discoveries that were borne of our total synthesis efforts, including a new Lewis acid-templated Diels-Alder reaction, the previously undescribed atrop-abyssomicin C, a facile Brønsted...

A Brønsted acid promoted direct aminoalkylation of various indoles with trifluoromethyl oxazolidine is described. A catalytic amount of triflic acid provided straightforward access to the corresponding trifluoromethyled amino esters under mild reaction conditions and a short reaction time of 4 h. On further hydrogenolysis and hydrolysis of ester, the synthesis of indole derived unnatural triflu...