Direct Conversion of Phosphonates to Phosphine Oxides: An Improved Synthetic Route to Phosphines Including the First Synthesis of Methyl JohnPhos
作者:Alexander J. Kendall、Chase A. Salazar、Patrick F. Martino、David R. Tyler
DOI:10.1021/om500854u
日期:2014.11.10
reaction intermediate. A diverse array of phosphonates was converted to phosphine oxides using a variety of Grignard reagents for direct carbon–phosphorus functionalization. This new methodology especially simplifies the synthesis of dimethylphosphino (RPMe2)-type phosphines by using air-, water-, and silica-stable intermediates. To highlight this reaction, a new Buchwald-type ligand ([1,1′-biphenyl]-
Gold(I)‐Catalyzed Synthesis of Six‐Membered P,O‐Heterocycles
<i>via</i>
Hydration/Intramolecular Cyclization Cascade Reaction
作者:Shan Zhang、Haiyang Cheng、Sheng Mo、Shiwei Yin、Zunting Zhang、Tao Wang
DOI:10.1002/adsc.201900605
日期:2019.9.17
Herein, we report the synthesis of six‐membered P,O‐heterocycles from dialkynylphosphine oxides. By using gold(I) complexes, the chemoselectivity of the reaction was switched from literature‐reported double hydration to a hydration/intramolecularcyclization cascade. Control experiments indicated that the first alkyne hydration product is an intermediate of the reaction. In addition, a density functional
Z/E ratios and enantioselectivities (up to >95/5 Z/E and 97% ee), which could be transformed into versatile optically active phosphine oxide derivatives. X-ray single crystalstructures of chiral N,N′-dioxides with rare-earth metal triflates revealed how the metal center and ligand structure affect the enantioselectivity.
已开发了手性th(III)催化的二炔基膦氧化物的硫共轭加成反应,以构建P-立体异构中心。在反应条件下,在炔烃末端位置具有芳基,烷基,烯基取代基的二炔基膦氧化物是可容许的。以中等至良好的收率(高达92%的收率)获得了具有较高Z / E比和对映选择性(高达> 95/5 Z / E和97%ee)的相应含P,S化合物,可以对其进行转化成为通用的光学活性氧化膦衍生物。手性N,N'的X射线单晶结构-二氧化物与稀土金属三氟甲磺酸盐显示了金属中心和配体结构如何影响对映选择性。
Cobalt- or rhodium-catalyzed synthesis of 1,2-dihydrophosphete oxides via C–H activation and formal phosphoryl migration
作者:Shengbo Xu、Ruijie Mi、Guangfan Zheng、Xingwei Li
DOI:10.1039/d4sc00649f
日期:——
heterocycles with dialkynylphosphine oxides has been realized via cobalt/rhodium-catalyzed C–H bond activation. This protocol provides an efficient synthetic entry to functionalized 1,2-dihydrophosphete oxides in excellent yields via the merger of C–H bond activation and formal 1,2-migration of the phosphoryl group. Compared with traditional methods of synthesis of 1,2-dihydrophosphetes that predominantly
n-Tributylphosphine was found to efficiently catalyze the alpha-P addition of H-phosphonates, H-phosphinates, and H-phosphine oxide pronucleophiles on alkynes bearing phosphane oxide activating moieties. The reaction leads to 2-aryl-1-vinyl-1,1-diphosphane dioxide derivatives in good yields affording a new route to P - C - P backbones. The products of this reaction are easily converted to biologically important 1,1-bisphosphonates analogues.