Bis-N,N-aminophosphine (PNP) crosslinked poly(p-tert-butyl styrene) particles: A new support for heterogeneous palladium catalysts for Suzuki coupling reactions
作者:Vito Vece、Kai C. Szeto、Marc O. Charlin、Pascal Rouge、Aimery De Mallmann、Manel Taam、Pierre-Yves Dugas、Muriel Lansalot、Franck D'Agosto、Mostafa Taoufik
DOI:10.1016/j.catcom.2019.105715
日期:2019.9
This newsupport was characterized by thermogravimetric analysis, elemental analysis, laser diffraction, solid state NMR. The PNP moiety could allow monochelation to palladium. The resulting insoluble Pd-catalyst revealed to be very active for Suzuki cross-coupling with several substrates, allowing separation of the product from the catalyst by filtration. The final palladium PS-PNP catalyst could
Extremely Active Organocatalysts Enable a Highly Enantioselective Addition of Allyltrimethylsilane to Aldehydes
作者:Philip S. J. Kaib、Lucas Schreyer、Sunggi Lee、Roberta Properzi、Benjamin List
DOI:10.1002/anie.201607828
日期:2016.10.10
The enantioselective allylation of aldehydes to form homoallylic alcohols is one of the most frequently used carbon–carbon bond‐forming reaction in chemical synthesis and, for several decades, has been a testing ground for new asymmetric methodology. However, a general and highlyenantioselective catalytic addition of the inexpensive, nontoxic, air‐ and moisture‐stable allyltrimethylsilane to aldehydes
Process for photocatalysis and two-electron mixed-valence complexes
申请人:Nocera Daniel G.
公开号:US06863781B2
公开(公告)日:2005-03-08
Embodiments for the invention include a process for the production of hydrogen comprising a protic solution, a photocatalyst capable of a two-electron reduction of hydrogen ions; and a coproduct trap. The embodiment includes exposing the reaction medium to radiation capable of photoexciting the photocatalyst to produce hydrogen. The protic solution may comprise at least one of hydrohalic acid, a silane, and water, and the hydrohalic acid may be hydrochloric acid, hydrogen bromide, hydrogen fluoride or hydrogen iodide. The present application also describes novel transition metal compounds. Embodiments of the compounds include a compound comprising two transition metal atoms, wherein the transition metal atoms are in a two-electron mixed valence state and at least one transition metal is not rhodium; and at least one ligand capable of stabilizing the transition metal atom in a two-electron mixed valence state.
Studies of phosphorus–phosphorus nuclear-spin coupling in species with phosphorus–nitrogen bonds
作者:Ian J. Colquhoun、William McFarlane
DOI:10.1039/dt9770001674
日期:——
used to study 34 organophosphorus spacies with a P–N–P skeleton. The geminal 31P–31P coupling constant is large and positive in derivatives of three-co-ordinate phos-phorus and is increased by bulky or electronegative substituents on phosphorus. The results for several pairs of diastereoisomers, and also the temperature dependence, indicate a strong conformational dependence of the coupling which is
Organometallic derivatives of diphosphinoamines, X2PN(R)PX2. Reactions with carbonyl derivatives of group 6 metals and iron pentacarbonyl. The crystal structures of [Mo(CO)4PhN(P(OPh)2)2] and [W(CO)4iPrN(PPh2)2]
diphosphinoamines X2PN(R)PX2 (L) (R = Me or Ph, X = OCH2CF3 or OPh; R = Ph, X = OC6H4Br-p; R = iPr, X = Ph) react with group 6 metal carbonyl derivatives to yield the cis-chelate complexes [M(CO)4(L-PP′)]. The structures of cis-[Mo(CO)4PhN(P(OPh)2)2] (3d) and cis-[W(CO)4iPrN(PPh2)2] (4f) have been established by single crystal X-ray diffraction studies. Reactions with iron pentacarbonyl yield complexes
二膦胺X 2 PN(R)PX 2(L)(R = Me或Ph,X = OCH 2 CF 3或OPh; R = Ph,X = OC 6 H 4 Br- p ; R = i Pr,X = Ph)与6族金属羰基衍生物反应生成顺式-螯合物[M(CO)4(L-PP')]。的结构的顺式- [沫(CO)4 PHN(P(OPH)2)2 ](3D)和顺式- [W(CO)4我PRN(PPH 2)2 ](4F)是通过单晶X射线衍射研究确定的。与五羰基铁反应生成络合物,其中观察到配体的螯合或桥双齿配位方式。