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Aerobic cross-dehydrogenative coupling between terminal alkynes and hydrosilanes occurred in the presence of nanoporous gold catalyst under O2 atmosphere. A variety of alkynylsilanes were synthesized in good-to-high yields and the catalyst was easily recovered and reused many times. Furthermore, the chemoselective direct silyl protection of terminal acetylenes of alkynols over the hydroxyl groups was achieved with this catalytic system.

We report for the first time that zero-valent nanoporous gold (AuNPore) is a robust and green heterogeneous catalyst for α-C-H functionalization of various tertiary amines. AuNPore combines with molecular oxygen at 80 °C or tert-butyl hydrogen peroxide at room temperature and catalyses the heterogeneous cross-dehydrogenative coupling (CDC) reaction efficiently to afford the corresponding C-C and C-heteroatom coupling products in good to excellent yields with excellent reusability.

The nanoporous AuPd (AuPdNPore) alloy catalyst showed superior chemoselectivity and high catalytic activity for the direct 1,4-hydrosilylation of the conjugated cyclic enones with hydrosilane in comparison with the monometallic nanoporous Au and Pd catalysts. The enhanced catalytic properties of AuPdNPore arise mainly from the nanoporous structure and the synergistic effect of the AuPd alloy.

A novel catalytic property of nanoporous gold for activation of bis(pinacolato)diboron has been reported that allows the direct diboration of alkynes to proceed sufficiently in a heterogeneous process. The experimental results revealed that the nanoporous gold catalyst is able to cleave the B–B bond of bis(pinacolato)diboron without using any additives.

A novel catalytic property of nanoporous gold for activation of bis(pinacolato)diboron has been reported that allows the direct diboration of alkynes to proceed sufficiently in a heterogeneous process. The experimental results revealed that the nanoporous gold catalyst is able to cleave the B–B bond of bis(pinacolato)diboron without using any additives.

We report for the first time the highly selective semihydrogenation of alkynes using the unsupported nanoporous gold (AuNPore) as a catalyst and organosilanes with water as a hydrogen source. Under the optimized reaction conditions, the present semihydrogenation of various terminal- and internal-alkynes affords the corresponding alkenes in high chemical yields and excellent Z-selectivity without any over-reduced alkanes. The use of DMF as solvent, which generates amines in situ, or pyridine as an additive is crucial to suppress the association of hydrogen atoms on AuNPore to form H(2) gas, which is unable to reduce alkynes on the unsupported gold catalysts. The AuNPore catalyst can be readily recovered and reused without any loss of catalytic activity. In addition, the SEM and TEM characterization of nanoporosity show that the AuNPore catalyst has a bicontinuous 3D structure and a high density of atomic steps and kinks on ligament surfaces, which should be one of the important origins of catalytic activity.

The nanoporous AuPd (AuPdNPore) alloy catalyst showed superior chemoselectivity and high catalytic activity for the direct 1,4-hydrosilylation of the conjugated cyclic enones with hydrosilane in comparison with the monometallic nanoporous Au and Pd catalysts. The enhanced catalytic properties of AuPdNPore arise mainly from the nanoporous structure and the synergistic effect of the AuPd alloy.