82017-87-6Relevant academic research and scientific papers
FUNCTIONALIZED PHOSPHONATES VIA MICHAEL ADDITION
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Paragraph 0238; 0239; 0255; 0256, (2018/03/10)
Provided herein are functionalized phosphonates and methods for making same via phosphite addition to an atom alpha to an electron withdrawing group. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.
Mitsunobu Reaction Using Basic Amines as Pronucleophiles
Huang, Hai,Kang, Jun Yong
, p. 6604 - 6614 (2017/07/15)
A novel protocol for extending the scope of the Mitsunobu reaction to include amine nucleophiles to form C-N bonds through the utilization of N-heterocyclic phosphine-butane (NHP-butane) has been developed. Both aliphatic alcohols and benzyl alcohols are suitable substrates for C-N bond construction. Various acidic nucleophiles such as benzoic acids, phenols, thiophenol, and secondary sulfonamide also provide the desired products of esters, ethers, thioether, and tertiary sulfonamide with 43-93% yields. Importantly, C-N bond-containing pharmaceuticals, Piribedil and Cinnarizine, have been synthesized in one step from the commercial amines under this Mitsunobu reaction system.
Amine-Catalyzed Phospha-Michael Reaction of α,β-Unsaturated Aldehydes and Ketones with Multifunctional N-Heterocyclic Phosphine-Thioureas as Phosphonylation Reagent
Huang, Hai,Kang, Jun Yong
supporting information, p. 4372 - 4375 (2016/10/21)
An efficient amine-catalyzed phospha-Michael addition reaction of α,β-unsaturated aldehydes/ketones with N-heterocyclic phosphines for the synthesis of ?-ketodiazaphosphonates has been developed. With freedom from nucleophile additives, this mild process affords a range of structurally diverse ?-ketodiazaphosphonates in moderate to excellent yields. Importantly, various α,β-unsaturated ketones were also tolerated in this process and gave moderate yields.
Controlled acrylate insertion regioselectivity in diazaphospholidine- sulfonato palladium(II) complexes
Wucher, Philipp,Roesle, Philipp,Falivene, Laura,Cavallo, Luigi,Caporaso, Lucia,Goettker-Schnetmann, Inigo,Mecking, Stefan
, p. 8505 - 8515 (2013/02/23)
Diazaphospholidine-sulfonato Pd(II) complexes [{κ2-P,O-(N- Ar2C2H4N2P)C6H 4SO3}PdMe(L)] 1-L (L = dmso, pyridine, lutidine, or μ-LiCl(solvent); 1a: Ar = Ph, 1b: Ar = 2-MeC6H4, 1c: Ar = 2-MeOC6H4, 1d: Ar = 2,4,6-Me3C 6H2, 1e: Ar = 2,6-iPr2C6H 3, 1f: Ar = 2,6-(p-tolyl)2C6H3) were prepared and structurally characterized. The regioselectivity of methyl acrylate (MA) insertion into the Pd-Me bond is entirely inverted from >93% 1,2-insertion for bulky substituents (1d-f, yielding the insertion products [(PO)Pd{κ2-C,O-CH2CHMeC(O)OMe], 12) to the usual electronically controlled 2,1-insertion (>95%) for the less bulky Ar = Ph (1a, yielding the insertion product [(PO)Pd{κ2-C,O- CHEtC(O)OMe], 11, and β-H elimination product methyl crotonate). DFT studies underline that this is due to a more favorable insertion transition state (2,1- favored by 12 kJ mol-1 over 1,2- for 1a) vs destabilization of the 2,1-insertion transition state in 1d,e. By contrast, MA insertion into the novel isolated and structurally characterized hydride and deuteride complexes [{κ2-P,O-(N-Ar2C 2H4N2P)C6H4SO 3}PdR(lutidine)] (Ar = 2,6-iPr2C6H3; 9e: R = H, 10e: R = D) occurs 2,1-selectively. This is due to the insertion occurring from the isomer with the P-donor and the olefin in trans arrangement, rather than the insertion into the alkyl from the cis isomer in which the olefin is in proximity to the bulky diazaphospholidine. 1a-f are precursors to active catalysts for ethylene polymerization to highly linear polyethylene with M n up to 35 000 g mol-1. In copolymerization experiments, norbornene was incorporated in up to 6.1 mol % into the polyethylene backbone.
Complexes of sterically-hindered diaminophosphinothiolate ligands with Rh(I), Ni(II) and Pd(II)
Robbie, Alasdair J.,Cowley, Andrew R.,Jones, Michael W.,Dilworth, Jonathan R.
experimental part, p. 1849 - 1856 (2011/08/04)
Two new sterically demanding diaminophosphinothiolate ligands (HL 1 and HL2) have been prepared and the X-ray crystal structure of the Li salt of HL2 has been determined. The complex [Pd(L1)2] was fully characterized, but in contrast to other phosphinothiolates, complexes with the M(L)3 stoichiometry could not be prepared. Reaction of LH1 with Ni(II) led to cleavage of the arythiolate group and isolation of a thiolate bridged dimer, confirmed by an X-ray crystal structure. The Rh(I) complexes [Rh(nbd)L] (L = L1, L2) were characterized including an X-ray structure.
Structure-Analytical Investigations of P-Substituted 1,3,2- Diazaphospholidines
Puntigam, Oliver,Hajdok, Imre,Nieger, Martin,Niemeyer, Mark,Strobel, Sabine,Gudat, Dietrich
scheme or table, p. 988 - 994 (2011/09/12)
2-Diphenylphosphanyl-1,3,2-diazaphospholidines were prepared via metathesis from 2-chloro-1,3,2-diazaphospholidines and LiPPh2. For some of the products, symmetrisation to tetraphenyldiphosphane and 2,2′-bis-1,3,2- diazaphospholidinyls was observed. Most of the derivatives were characterised by single-crystal X-ray diffraction, which showed that all compounds studied feature elongated exocyclic P-Cl or P-P-bonds, respectively. The extent of this bond lengthening is in the P-phosphanyl-substituted species similar and in the P-chloro-derivatives less pronounced than in corresponding CC-unsaturated 1,3,2-diazaphospholenes. Structure correlation involving comparison of exocyclic P-X and endocyclic P-N distances suggests that n(N)/σ(P-X) hyperconjugation contributes strongly to the bond lengthening and induces a perceptible weakening of the P-P bonds in 2-diphenylphosphanyl-1,3,2- diazaphospholidines, which should render these compounds interesting substrates for P-P bond activation reactions. Copyright
N-Heterocyclic phosphenium cations: Syntheses and cycloaddition reactions
Caputo, Christine A.,Price, Jacquelyn T.,Jennings, Michael C.,McDonald, Robert,Jones, Nathan D.
, p. 3461 - 3469 (2008/09/21)
A series of trifluoromethanesulfonate (OTf) salts of N-heterocyclic phospheniums (NHP) bearing phenyl (1a), para-methoxyphenyl (1b), 2,6-diisopropylphenyl (1c) and mesityl (1d) substituents is reported. The compounds 1b-d are made by a modification to a literature procedure that improves the overall yields for 1c and 1d by 15 and 23%, respectively. Two unwanted side-products in the synthesis of 1d, the diammonium salt, [(2,6-iPr-C6H3)N(H)2CH2CH 2N(H)2(2,6-iPr-C6H3)]Cl2 (4) and the bisphosphine (2,6-iPr-C6H3)N(PCl 2)CH2CH2N(PCl2)(2,6-iPr-C 6H3) (5), are crystallographically characterized, as is the intermediate cyclic chlorophosphine, C1PN(4-OMe-C6H 4)CH2CH2N(4-OMe-C6H4) (3b). The phenyl-substituted NHP 1a is fully characterized, including by X-ray crystallography, for the first time; this compound contains a short P-O contact of 2.1850(14) A Cycloaddition reactions of 1a-d with 2,3-dimethyl-1,3- butadiene give the expected spirocyclic phospholeniums, 7,8-dimethyl-1,4-diaryl- 1,4-diaza-5-phopshoniaspiro[4.4]non-7-ene, as their OTf salts (6a-d), while reactions with N,N′-dimesityl-1,4-diaza-1,3-butadiene give, except in the case of 1c, which is too bulky to react, the aza analogues, 1,4-dimesityl-6,9- diaryl-1,4,6,9-tetraaza-5-phosphoniaspiro[4.4]non-2-ene (7a, 7b and 7d). The sterically congested 7d is in thermal equilibrium with 1d and free diazadiene, and undergoes a substitution reaction with 2,3-dimethyl-1,3-butadiene to give 6d.
Chiral phosphoramide-catalyzed aldol additions of ketone trichlorosilyl enolates. Mechanistic aspects
Denmark, Scott E.,Pham, Son M.,Stavenger, Robert A.,Su, Xiping,Wong, Ken-Tsung,Nishigaichi, Yutaka
, p. 3904 - 3922 (2007/10/03)
The mechanism of the catalytic, enantioselective addition of trichlorosilyl enolates to aldehydes has been investigated. Kinetic studies using ReactIR and rapid injection NMR (RINMR) spectroscopy have confirmed the simultaneous operation of dual mechanist
La liaison phosphazene dans quelques nouveaux iminophospholanes. Diversite de comportement reactionnel
Marre, Marie Rose,Sanchez, Michel,Brazier, Jean Francois,Wolf, Robert,Bellan, Jacques
, p. 456 - 468 (2007/10/02)
Using the Staudinger reaction, we have synthesized twelve iminophospholanes (1-12) with dioxa (1-4), oxaza (5,6), and diaza (7-12) ring systems.We have never observed any phosphazene bond dimerization with diazaphospholane compounds, whatever the nature of the group on the imino atom.For the tetramethyl dioxaphospholane compounds (1,2,4), the thermal rearrangement occurs with the intracyclic oxygen atom.Last of all, the reactivity of the phosphazene bond with methanol differs according to the nature of the ring: addition leading to the pentacoordinated species in pinacolic compounds, intermolecular associations (hydrogen bonding) in diazaphospholane derivatives.
