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We herein report that MoS2 with oxygen-implanting modification (O-MoS2) can work as a multifunctional catalyst to achieve the one-pot quinoline synthesis from basic nitroarenes and aliphatic alcohols.

Herein, a strategy is developed for efficient production of l,3-propanediol via the hydrolysis of 1,3-dioxane by the in situ transformation of the co-product formaldehyde (HCHO) in the presence of Eu(OH)3. The reversible hydrolysis reaction is promoted to yield 98% conversion and 99% 1,3-propanediol selectivity. Furthermore, HCHO is converted to formic acid (HCOOH) which could act as an acidic catalyst in the hydrolysis of 1,3-dioxane. The combination of FT-IR and control experiments demonstrates that HCOOH is generated via the hydrolysis of formate species which formed on the surface of Eu(OH)3.

The efficient cleavage of lignin β-O-4 ether bonds to produce aromatics is a challenging and attractive topic. Recently a growing number of studies have revealed that the initial oxidation of CαHOH to CαO can decrease the β-O-4 bond dissociation energy (BDE) from 274.0 kJ mol−1 to 227.8 kJ mol−1, and thus the β-O-4 bond is more readily cleaved in the subsequent transfer hydrogenation, or acidolysis. Here we show that the first reaction step, except in the above-mentioned pre-oxidation methods, can be a Cα–OH bond dehydroxylation to form a radical intermediate on the acid-redox site of a NiMo sulfide catalyst. The formation of a Cα radical greatly decreases the Cβ–OPh BDE from 274.0 kJ mol−1 to 66.9 kJ mol−1 thereby facilitating its cleavage to styrene, phenols and ethers with H2 and an alcohol solvent. This is supported by control experiments using several reaction intermediates as reactants, analysis of product generation and by radical trap with TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy) as well as by density functional theory (DFT) calculations. The dehydroxylation–hydrogenation reaction is conducted under non-oxidative conditions, which are beneficial for stabilizing phenol products.

We present an experimental and computational study of the elementary steps of hydrazine hydrogen transfer on crystalline MoO2, and demonstrate its unique bifunctional metallic-basic properties in a catalytic hydrogenation reaction. Density functional theory (DFT) calculations suggest that the stepwise hydrogen transfer via the prior cleavage of the N–H bond rather than the N–N bond, is the key step to create the dissociated hydride and proton species on the dual Mo and O sites, marking its difference with common oxides. Crystalline MoO2 shows exceptionally high chemoselectivity toward the nitro reduction over CC, CC, and CN groups at room temperature and lower, down to 0 °C, rendering it as a promising catalytic material for hydrogenation reactions.