Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Chemistry. 2011 Jan 24;17(4):1261-7. doi: 10.1002/chem.201002761. Epub 2010 Dec 1.
The Sn-W mixed oxide prepared by calcination of the Sn-W mixed hydroxide precursor with a Sn/W molar ratio of 2:1 at 800 °C (SnW2-800) acts as an efficient heterogeneous catalyst for the hydration of alkynes. Structurally diverse terminal and internal alkynes, including aromatic, aliphatic, and double-bond-containing ones, can be converted into the corresponding ketones in moderate to high yields. The catalytic activity of SnW2-800 is much higher than those of previously reported heterogeneous catalysts and commonly utilized acid catalysts. The observed catalysis was truly heterogeneous, and the retrieved catalyst can be reused at least three times with retention of its high catalytic performance. The reaction rate for the SnW2-800-catalyzed hydration was decreased by addition of 2,6-lutidine and the hydration hardly proceeded in the presence of an equimolar amount of this compound with respect to that of the Brønsted acid sites in SnW2-800. Therefore, the present hydration is mainly promoted by the Brønsted acid sites in SnW2-800.
由摩尔比为 2:1 的 Sn-W 混合氢氧化物前体在 800°C 下煅烧得到的 Sn-W 混合氧化物（SnW2-800）用作炔烃水合的高效多相催化剂。结构多样的末端和内部炔烃，包括芳族、脂肪族和含双键的炔烃，可以中等至高收率转化为相应的酮。SnW2-800 的催化活性远高于先前报道的多相催化剂和常用的酸催化剂。观察到的催化作用是真正的多相的，回收的催化剂至少可以重复使用三次，并且保持其高催化性能。在添加 2,6- 二甲基吡啶的情况下，SnW2-800 催化的水合反应速率降低，并且在与 SnW2-800 中的 Brønsted 酸位等摩尔量的该化合物存在下，水合几乎不进行。因此，本水合主要由 SnW2-800 中的 Brønsted 酸位促进。
