Selective reduction of ketone/aldehydes to alcohols is of great importance in green chemistry and chemical engineering. Highly efficient catalysts are still demanded to work under mild conditions, especially at room temperature. Here we present a synergistic function of singleatom palladium (Pd 1 ) and nanoparticles (Pd NPs ) on TiO 2 for highly efficient ketone/aldehydes hydrogenation to alcohols at room temperature. Compared to simple but inferior Pd 1 /TiO 2 and Pd NPs /TiO 2 catalysts, more than twice activity enhancement is achieved with the Pd 1+NPs /TiO 2 catalyst that integrates both Pd 1 and Pd NPs on mesoporous TiO 2 supports, obtained by a simple but large-scaled spray pyrolysis route. The synergistic function of Pd 1 and Pd NPs is assigned so that the partial Pd 1 dispersion contributes enough sites for the activation of C=O group while Pd NPs site boosts the dissociation of H 2 molecules to H atoms. This work not only contributes a superior catalyst for ketone/aldehydes hydrogenation, but also deepens the knowledge on their hydrogenation mechanism and guides people to engineer the catalytic behaviors as needed.

The multicomponent reactions (MCRs) consist of two or more synthetic steps which are carried out without isolation of any intermediate thus reducing time, saving money, energy and raw materials. The development of MCRs in the presence of molecular iodine is an efficient approach that meets with the requirements of sustainable chemistry. The aim of this review is to highlight the synergistic effect of the combined use of MCRs and molecular iodine for the development of new eco-compatible methodologies for organic chemistry.

Two novel thorium-based metal−organic frameworks (MOFs), namely Th-SINAP-7 and Th-SINAP-8, have been synthesized via the solvothermal reactions of thorium nitrate and 1,4-or 2,6-naphthalenedicarboxylic acid in the presence of acid modulators. Bearing the rigid aromatic architectures, Th-SINAP-7 and Th-SINAP-8 exhibit exceptional chemical (from pH 1 to 12) and thermal stabilities (up to 520 °C), as well as ionizing radioresistance (2 × 10 5 Gy β and γ irradiations). The highly porous nature and conjugated π-electrons of naphthalene on the organic linkers endow high affinity of both MOFs toward I 2 molecules owning to the charge transfer between π-electrons of the host networks and the guest iodine molecules, as evidenced by combined techniques including of FTIR, PXRD, SEM-EDS, UV−vis spectroscopy, XPS, and Raman spectroscopy. Particularly, Th-SINAP-8 can efficiently remove >99% I 2 from cyclohexane solution and exhibit guest uptake of iodine vapor with an adsorption capacity of 473 mg/g.

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A mild and metal-free synthesis of aryl isocyanates from arylamines under an atmosphere of CO was developed. The carbamic acid intermediate, derived from the arylamine starting material and CO in the presence of DBU, is dehydrated by activated sulfonium reagents to generate the corresponding isocyanate. The latter can be detected by in situ IR and trapped by various amines and alcohols to make unsymmetrical ureas and carbamates, respectively. Dicarbamates can also be prepared in good yields via the mild dehydration of the corresponding dicarbamic acids.

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