摘要
用量子化学 AM1方法优化了 1-苯基二苯并膦 (PDBP)和三苯基膦 (TPP)的几何构型 ,比较了两种化合物的电子结构和空间结构 ,发现 PDBP作为羰基合成铑膦催化剂的配体要优于三苯基膦 (TPP) ;系统研究了 PDBP的合成方法 ,其最佳合成条件为 :在无水无氧的条件下 ,采用二乙胺锂与溴化四苯基膦摩尔比为 3,反应温度为2 2℃ ,反应 5 h,反应后酸化 ,p H值为 1~ 2 ,产物收率可达到 85 %~ 88% .采用元素分析、红外、核磁等方法 ,对其结构进行了表征 ,并将 PDBP用于丙烯氢甲酰化反应的催化剂配体 .实验证明 ,在相同的反应条件下 ,以其为配体的催化剂活性约是目前工业上使用的以三苯基膦为配体的催化剂的 1.2倍 ,选择性约为其 1.7倍 .
First, the geometry optimization for 1\|phenyldibenzophosphole (PDBP) and triphenylphosphine (TPP) were carried out using quantum chemical AM1 method. It is shown from both the electronic and stereo structural analyses, that PDBP is a superior coordinate ligand as compared with TPP, which was employed in the rhodium/phosphonium catalyst for the hydroformylation reaction. Secondly, the synthesis of PDBP was investigated and the best reaction conditions were found as follows: the molar ratio of LiN(C 2H 5) 2/(C 6H 5) 4PBr is 3, and the reaction is carried out at 22 ℃ for 5 h, then HCl is added until the pH value reaches 1~2, thus a yield of PDBP of 85%~88% is attained. The structure of the target product PDBP was characterized by IR and NMR spectrometries and the chemical composition was determined by elemental analyses. Lastly, the catalytic performances of Rh complexes using PDBP and TPP as ligands, respectively, for the hydroformylation of propene were determined. It is found that under the same conditions, catalytic activity of catalyst used PDBP as ligand is about 1.2 times than that of catalyst used TPP as ligand, and selectivity to n \|butylaldehyde of the former is about 1.7 times that of the later.
出处
《分子催化》
EI
CAS
CSCD
北大核心
2001年第2期124-128,共5页
Journal of Molecular Catalysis(China)
基金
国家"九五"科技攻关项目!( 96-A12 -0 4-0 5 )