18899-64-4Relevant articles and documents
Mechanism of phosphorus-carbon bond cleavage by lithium in tertiary phosphines. An optimized synthesis of 1,2-bis(phenylphosphino)ethane
Dogan, John,Schulte, Jurgen B.,Swiegers, Gerhard F.,Wild, S. Bruce
, p. 951 - 957 (2000)
Conditions influencing the extent of P-C(aryl) vs P-C(alkyl) bond cleavage in the reaction of Ph2P(CH2)2PPh2 with lithium in THF have been investigated. The results complement and elucidate earlier work; they indicate that the mechanism of P-C bond cleavage in tertiary phosphines of this type involves a thermodynamic equilibrium between P-C(aryl) and P- C(alkyl) cleaved radicals and anions, followed by reaction and stabilization of these as lithium salts. The addition of water to the reaction mixture causes a reestablishment of the cleavage equilibrium prior to the formation of the secondary phosphines. A mechanism involving competitive release of leaving groups as the thermodynamically most stable anion or radical has been proposed. The preparation of (R*, R*)-(±)/(R*, S*)-PhP(H)(CH2)2P(H)Ph by this route has been optimized.
Zirconium-Catalyzed Intermolecular Double Hydrophosphination of Alkynes with a Primary Phosphine
Bange, Christine A.,Waterman, Rory
, p. 6413 - 6416 (2016)
Catalytic double hydrophosphination of internal alkynes and primary phosphines is possible using a zirconium complex, [κ5-N,N,N,N,C-(Me3SiNCH2CH2)2NCH2CH2NSiMe2CH]Zr (1). The reaction proceeds via stepwise hydrophosphination to give vinyl phosphine products, which can be isolated or further converted to the respective 1,2-bis(phosphino)ethane (i.e., double hydrophosphination). The catalysis is highly selective for formation of secondary phosphine products.
1,3,6-azadiphosphacycloheptanes: A novel type of heterocyclic diphosphines
Karasik, Andrey A.,Balueva, Anna S.,Moussina, Elvira I.,Naumov, Roman N.,Dobrynin, Alexey B.,Krivolapov, Dmitry B.,Litvinov, Igor A.,Sinyashin, Oleg G.
, p. 125 - 132 (2008/09/18)
The novel type of seven-membered cyclic diphosphines, namely 1,3,6-azadiphosphacycloheptanes, has been synthesized by condensation of 1,2-bis(phenylphosphino)ethane, formaldehyde, and primary amines (aniline, p-toluidine, benzylamine, and 5-aminoisophthalic acid) as a mixture of rac-and meso-stereoisomers. The structures of rac-stereo-isomers of N-tolyl and N-(3′,5′-dicarboxyphenyl)-substituted diphosphines were investigated by X-ray crystal structure analyses. The stereoisomers of N-(3′,5′- dicarboxyphenyl)-substituted compound were separated at a preparative scale, and their platinum(II) dichloride complexes were obtained. The corresponding meso-isomer readily forms P,P-chelate complex with [PtCl2(cod)], whereas the rac-stereoisomer forms oligomeric complex.