The new chiral aminodiphosphinite ligands are readily prepared from chiral amino acids. These compounds were characterized by 13C and 31P NMR spectroscopy and their behaviour as homogeneous catalysts was investigated in the linear dimerization of butadiene.
新的手性氨基二亚膦酸酯配体易于从手性氨基酸制备。这些化合物通过13 C和31 P NMR光谱进行表征,并在丁二烯的线性二聚反应中研究了它们作为均相催化剂的行为。
NICKEL-CATALYZED REACTION OF BUTADIENE. FORMATION OF 2-METHYLENEVINYLCYCLOPENTANE AND ADDITION OF AMINE TO BUTADIENE
The cyclodimerization of butadiene catalyzed by bis(tri-n-butylphosphine)dibromonickel combined with sodium borohydride was investigated, using amines as protonic solvents. At 80°C a large amount of amine-adducts to butadiene was obtained together with 2-methylenevinylcyclopentane. The adducts were formed exclusively at room temperature.
The stereochemistry of cross-coupling adducts of norbornenes with butadiene catalyzed by Ni complex generated in situ by NiBr2(Ph3P)2 and NaBH4 in ethanol was investigated. The configuration of four-member cross coupling products could be confirmed by means of independent synthesis.
研究了由 NiBr2(Ph3P)2 和 NaBH4 在乙醇中原位生成的 Ni 配合物催化的降冰片烯与丁二烯交叉偶联加合物的立体化学。四元交叉偶联产物的构型可以通过独立合成来确定。
Novel palladium-catalysed cyclodimerization of butadiene in the presence of carbon dioxide and water
The first example is reported of a palladium-catalysed Cyclodimerization of butadiene to 2-vinylmethylenecyclopentane occurring in catalytic turnovers and yields far superior to the nickel-based systems, which are claimed to be specific for cyclodimerization reactions.