The first manganese‐catalyzedhydrogenation of esters to alcohols has been developed. The combination of Mn(CO)5Br with [HN(CH2CH2P(Et)2)2] leads to a mixture of cationic and neutral Mn PNP pincer complexes, which enable the reduction of various ester substrates, including aromatic and aliphatic esters as well as diesters and lactones. Notably, related pincer complexes with isopropyl or cyclohexyl
Hydrogenation of esters to alcohols with a well‐defined iron iPr2PNP pincercomplex has been recently reported by us and other groups. We now introduce a novel and sterically less hindered Et2PNP congener that provides superior catalytic activity in the hydrogenation of various carboxylic acid esters and lactones compared to the known complex. Successful hydrogenation proceeds under relatively mild
series of molybdenum(0), (I) and (II) complexes ligated by different PNP and NNN pincer ligands were synthesized and structurally characterized. Along with previously described Mo−PNP complexes Mo‐1 and Mo‐2, all prepared compounds were tested in the catalytichydrogenation of aromatic nitriles to primary amines. Among the applied catalysts, Mo‐1 is particularly well suited for the hydrogenation of electron‐rich
Low-Valent Molybdenum PNP Pincer Complexes as Catalysts for the Semihydrogenation of Alkynes
作者:Niklas F. Both、Anke Spannenberg、Kathrin Junge、Matthias Beller
DOI:10.1021/acs.organomet.1c00709
日期:2022.7.25
Low-valent molybdenum PNP pincer complexes were studied as catalysts for the semihydrogenation of alkynes. For that purpose, tBu-substituted PNP complexes PNPtBuMo(CO)2 (6a) and PNPtBuMo(CO)3 (6c) and the NNP complex NNPiPrMo(CO)2(PPh3) ((rac)-7) were synthesized and characterized. By utilizing the cyclohexyl-substituted complex PNPCyMo(CO)2(CH3CN) (5a), several diphenylacetylene derivatives are transformed
研究了低价钼PNP 钳配合物作为炔烃半氢化催化剂。为此, t Bu 取代的 PNP 配合物 PNP t Bu Mo(CO) 2 ( 6a ) 和 PNP t Bu Mo(CO) 3 ( 6c ) 以及 NNP 配合物 NNP i Pr Mo(CO) 2 (PPh 3 ) ( ( rac ) -7 ) 被合成并表征。通过利用环己基取代的复合物PNP Cy Mo(CO) 2 (CH 3 CN) ( 5a ),几种二苯乙炔衍生物可转化为相应的( Z )-烯烃,具有良好至非常好的非对映选择性(高达91:9)。机理实验表明了包括金属-配体协同作用在内的外球机制。
Methods of preparation of an olefin oligomerization catalyst
申请人:Knudsen D. Ronald
公开号:US20050187391A1
公开(公告)日:2005-08-25
A method of making a catalyst for use in oligomerizing an olefin comprising a chromium-containing compound, a pyrrole-containing compound, a metal alkyl, a halide-containing compound, and optionally a solvent, the method comprising contacting a composition comprising the chromium-containing compound and a composition comprising the metal alkyl, wherein the composition comprising the chromium-containing compound is added to the composition comprising the metal alkyl.