4455-75-8Relevant academic research and scientific papers
Copper-Catalyzed C?P Cross-Coupling of (Cyclo)alkenyl/Aryl Bromides and Secondary Phosphine Oxides with in situ Halogen Exchange
Stankevi?, Marek,Wo?nicki, Pawe?
, p. 3484 - 3491 (2021/07/22)
An efficient protocol for concurrent tandem halogen exchange/C?P cross-coupling of cycloalkenyl bromides and secondary phosphine oxides has been developed. The catalytic system is based on cheap and air-stable copper(I) iodide as the precatalyst, commercially available N,N’-dimethylethylenediamine as the ligand, and Cs2CO3 or K2CO3 as the base. The use of sodium iodide as an additive reduces the excessive use of organic bromides to near-stoichiometric by promoting the in situ transformation to the corresponding iodides. Diarylphosphine oxides undergo cycloalkenylation with 35–99 % yields and dicyclohexylphosphine oxide with 30–53 % yields. In the case of acyclic alkenyl bromides the cross-coupling products undergo conjugate addition of diphenylphosphine oxide and satisfying yields are observed only for internal olefins. In the case of aryl bromides satisfying yields (43–72 %) are observed only for sterically unhindered arenes or arenes possessing an ortho-directing group. Cycloalkenylphosphine oxides prepared in the cross-coupling reaction undergo base-catalyzed and base-promoted conjugate addition to give bis(phosphinoyl)cycloalkanes.
Synthesis, Structure, and Solution Studies of Lithiated Allylic Phosphines and Phosphine Oxides
Eren, Nimrod M.,Orr, Samantha A.,Thompson, Christopher D.,Border, Emily C.,Stevens, Michael A.,Blair, Victoria L.
, p. 2080 - 2090 (2020/06/05)
This study reports a new series of 12 α-lithiated allylic phosphines and phosphine oxides. By incorporating Lewis base donors including diethyl ether (Et2O), tetrahydrofuran (THF), N,N,N′,N′,-tetramethylethylenediamine (TMEDA), and N,N,N′,N′,N″,-pentamethyldiethylenetriamine (PMDETA), nine complexes were structurally characterized by single-crystal X-ray crystallography. This includes novel dilithiated allylic phosphine 4 [PhP{CHCHCH2Li(TMEDA)}2] and a rare hemisolvated lithiated phosphine oxide 6 [{Ph2P(O)CHC(Me)CH2Li}2(TMEDA)]. Interestingly, in the solid state, P(III) complexes take advantage of Li-πinteractions to the newly formed delocalized system, in comparison to P(V) complexes where the oxophillic nature of the lithium atom dominates. All 12 complexes were fully characterized in the solution state by multinuclear NMR spectroscopy. DFT calculations on isomers of monomeric lithiated complex 3 [Ph2PCHC(Me)CH2Li(PMDETA)] described the low energy barrier between transition steps of the subtle delocalization of the allylic chain.
Asymmetric synthesis of trans-disubstituted cyclopropanes using phosphine oxides and phosphine boranes
Clarke, Celia,Foussat, Stephanie,Fox, David J.,Pedersen, Daniel Sejer,Warren, Stuart
supporting information; experimental part, p. 1323 - 1328 (2009/12/04)
The stereocontrolled synthesis of trans-disubstituted cyclopropylketones has been achieved from β-alkyl, γ-benzoyl phosphine oxides via a three-step cascade reaction incorporating an acyl transfer, phosphinoyl transfer and cyclisation to form the cyclopropane. Using Evans' chiral oxazolidinone auxiliary and by masking the phosphine oxide moiety as a phosphine borane we have extended the method to the synthesis of enantiomerically-enriched trans-disubstituted cyclopropyl ketones.
An efficient protocol for Sharpless-style racemic dihydroxylation
Eames, Jason,Mitchell, Helen J.,Nelson, Adam,O'Brien, Peter,Warren, Stuart,Wyatt, Paul
, p. 1095 - 1104 (2007/10/03)
Racemic dihydroxylation of alkenes is efficiently accomplished with catalytic osmium (added as OsCl3), stoichiometric K3Fe(CN)6 and quinuclidine under conditions similar to those of the Sharpless asymmetric hydroxylation.
Synthesis of a functionalized allylic phosphine oxide
Harmata, Michael,Carter, Kevin W.
, p. 3027 - 3033 (2007/10/03)
A functionalized allylic phosphine oxide has been prepared by regioselective bromination of 2-(methyldiphenylphosphinoyl)-1-propene followed by nucleophilic substitution with acetate. Hydrolysis and protection yielded the target compound.
Synthesis of (R)- or (S)-diphenylphosphinoyl hydroxy aldehydes and 1,2-diols using Mukaiyama's bicyclic aminal methodology and Sharpless asymmetric dihydroxylation
O'Brien, Peter,Warren, Stuart
, p. 2129 - 2138 (2007/10/03)
Two different approaches to diphenylphosphinoyl hydroxy aldehydes and 1,2-diols are compared. A lengthy chiral auxiliary approach using proline-derived aminals enables hydroxy aldehydes and 1,2-diols of known absolute stereochemistry and high enantiomeric
Asymmetric dihydroxylations of allylic phosphine oxides
Nelson,O'Brien,Warren
, p. 2685 - 2688 (2007/10/02)
Allylic phosphine oxides 6 undergo asymmetric dihydroxylation to yield 1,2 diols 9. The enantioselectivity of these reactions depends critically on the class and quantity of chiral ligand used. A model to explain the sense and degree of asymmetric inducti
Structure and Conformation of α'-Diphenylphosphinoyl Enones: X-Ray Structure of E-(5SR,6SR)-3,6-Dimethyl-5-diphenylphosphinoyl-7-triphenylmethoxyhept-2-en-4-one
Doyle, Michael J.,Hall, David,Raithby, Paul R.,Skelton, Nicholas,Warren, Stuart
, p. 517 - 524 (2007/10/02)
A series of α'-diphenylphosphinoyl enones has been prepared and their s-cis or s-trans conformations correlated with 1H NMR and IR spectra and an X-ray crystal structure of the title compound.The effect of chelation to cerium(III) is correlated with the r
SYNTHESIS OF METHYL- AND DIMETHYL-SUBSTITUTED ETHYLENE DIPHOSPHINE DIOXIDES AND THEIR COMPLEX-FORMING PROPERTIES
Antoshin, A. E.,Evreinov, V. I.,Kharitonov, A. V.,Pushin, A. N.,Yarkevich, A. N.,et al.
, p. 1647 - 1651 (2007/10/02)
Alkylation of diphenylphosphonous acid by allyl bromide leads (depending on the reaction conditions) to the formation of both diphenylallylphosphine oxide and diphenylpropenylphosphine oxide.Addition of phosphonous acids to diphenylpropenylphosphine and d
A Simple Preparation of Vinyl- or Allyldiphenylphosphine Oxides
Santelli-Rouvier, Christiane
, p. 64 - 66 (2007/10/02)
A general route to 2- or 2,2-substituted vinyldiphenylphosphine oxides or allyldiphenylphosphine oxides from ketones (or benzaldehyde) and the anion of methyldiphenylphosphine oxide is reported.The intially formed 2-hydroxyalkyldiphenylphosphine oxide is
