介孔ETS-10沸石担载Pd高效催化内炔氧化制备1,2-二酮

Pd Supported on Mesoporous ETS-10 Zeolite Catalyst with Superior Catalytic Performances in Synthesizing 1,2-Diones from the Oxidation of Internal Alkynes

使用担载Pd的介孔ETS-10(Pd/METS-10)催化剂在清洁的反应条件下,实现了内炔氧化合成1,2-二酮类衍生物.研究发现,催化剂上高分散的Pd(Ⅱ)和炔烃配位形成电子受体供体复合物(EDX)是反应顺利进行的关键.随后二甲基亚砜(DMSO)亲核进攻生成的EDX,相继发生加成和消除反应,从而生成目的产物.Pd/METS-10催化的内炔氧化反应具有优异的产物选择性和好的底物范围,能够同时兼容对称/不对称内炔,且对底物的电子性质和立体效应不敏感.此外,Pd/METS-10催化剂在反应中表现出优异的重复性能,在循环使用5次后没有明显的活性损失.最后,根据表征结果和控制实验结果,提出了Pd/METS-10催化的内炔氧化制备1,2-二酮的反应机理.

The 1,2-dione compounds was synthesized under clean reaction conditions over Pd/METS-10 catalyst.It has been found that the key step of the protocol is forming an electron donor-acceptor complex(EDX),as the coordination of Pd(II)and alkynyl.Then the nucleophilic addition and elimination reactions of dimethyl sulfoxide(DMSO)to the EDX were occurred,affording the target product.Pd/METS-10 catalyzed endo-acetylene oxidation possesses excellent product selectivity and good substrate scope.It is compatible with both symmetric and asymmetric endo-acetylene and is insensitive to the electronic properties and stereoscopic effects of the substrate.In addition,Pd/METS-10 catalyst showed excellent repetition performance in the reaction,with no significant loss of activity after five cycles.Finally,according to the characterization and control experiment results,the reaction mechanism of Pd/METS-10 catalyzed acetylene oxidation to produce 1,2-dione was proposed.