Salnikov Oleg G, Liu Hsueh-Ju, Fedorov Alexey, Burueva Dudari B, Kovtunov Kirill V, Copéret Christophe, Koptyug Igor V
International Tomography Center , SB RAS , 3A Institutskaya St. , 630090 Novosibirsk , Russia . Email:
Novosibirsk State University , 2 Pirogova St. , 630090 Novosibirsk , Russia.
Chem Sci. 2017 Mar 1;8(3):2426-2430. doi: 10.1039/c6sc05276b. Epub 2016 Dec 20.
Mechanistic insight into the semihydrogenation of 1-butyne and 2-butyne on Cu nanoparticles supported on partially dehydroxylated silica (Cu/SiO) was obtained using parahydrogen. Hydrogenation of 1-butyne over Cu/SiO yielded 1-butene with ≥97% selectivity. The surface modification of this catalyst with tricyclohexylphosphine (PCy) increased the selectivity to 1-butene up to nearly 100%, although at the expense of reduced catalytic activity. Similar trends were observed in the hydrogenation of 2-butyne, where Cu/SiO provided a selectivity to 2-butene in the range of 72-100% depending on the reaction conditions, while the catalyst modified with PCy again demonstrated nearly 100% selectivity. Parahydrogen-induced polarization effects observed in hydrogenation reactions catalyzed by copper-based catalysts demonstrate the viability of pairwise hydrogen addition over these catalysts. Contribution of pairwise hydrogen addition to 1-butyne was estimated to be at least 0.2-0.6% for unmodified Cu/SiO and ≥2.7% for Cu/SiO modified with PCy, highlighting the effect of surface modification with the tricyclohexylphosphine ligand.
利用仲氢对负载在部分脱羟基二氧化硅（Cu/SiO）上的铜纳米颗粒上1-丁炔和2-丁炔的半氢化反应进行了机理研究。在Cu/SiO上1-丁炔的氢化反应中，生成1-丁烯的选择性≥97%。用三环己基膦（PCy）对该催化剂进行表面改性，可将1-丁烯的选择性提高到近100%，不过代价是催化活性降低。在2-丁炔的氢化反应中也观察到了类似趋势，其中Cu/SiO根据反应条件对2-丁烯的选择性在72-100%范围内，而用PCy改性的催化剂再次显示出近100%的选择性。在铜基催化剂催化的氢化反应中观察到的仲氢诱导极化效应证明了在这些催化剂上成对加氢的可行性。对于未改性的Cu/SiO，成对加氢对1-丁炔的贡献估计至少为0.2-0.6%，对于用PCy改性的Cu/SiO，该贡献≥2.7%，突出了三环己基膦配体表面改性的效果。
