314730-65-9Relevant articles and documents
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.
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.