4663-13-2Relevant articles and documents
Spiro[1,2]oxaphosphetanes of nonstabilized and semistabilized phosphorus ylide derivatives: Synthesis and kinetic and computational study of their thermolysis
López, Jesús García,Sansores Peraza, Pablo M.,Iglesias, María José,Roces, Laura,García-Granda, Santiago,Ortiz, Fernando López
, p. 14570 - 14591 (2020/11/20)
A series of tri- and tetrasubstituted spiro-oxaphosphetanes stabilized by ortho-benzamide (oBA) and N-methyl ortho-benzamide (MoBA) ligands have been synthesized by the reaction of Cα,Cortho-dilithiated phosphazenes with aldehydes and ketones. They include enantiopure products and the first example of an isolated oxaphosphetane having a phenyl substituent at C3 of the ring. Kinetic studies of their thermal decomposition showed that the process takes place irreversibly through a polar transition state (ρ = -0.22) under the influence of electronic, [1,2], [1,3] steric, and solvent effects, with C3/P-[1,2] interactions as the largest contribution to ΔG of olefination. Inversion of the phosphorus configuration through stereomutation has been observed in a number of cases. DFT calculations showed that oBA derivatives olefinated through the isolated (N, O)(Ph, C6H4, C) oxaphosphetanes (Channel A), whereas MoBA compounds decomposed faster via the isomer (C6H4, O)(C, N, Ph) formed by P-stereomutation involving a MB2 permutational mechanism (Channel B). The energy barrier of P-isomerization is lower than that of olefination. Fragmentation takes place in a concerted asynchronous reaction. The thermal stability of oxaphosphetanes is determined by strong C3/P-[1,2] interactions destabilizing the transition state of olefination. The effect of charge distribution and C3/C4-[1,2] and C4/P-[1,3] steric and solvent interactions on ΔG was also evaluated.
Synthesis of polysubstituted olefins by Pd-catalyzed cross-coupling reaction of tosylhydrazones and aryl nonaflates
Barluenga, Jose,Florentino, Lucia,Aznar, Fernando,Valdes, Carlos
supporting information; experimental part, p. 510 - 513 (2011/03/22)
Aryl nonaflates are employed as electrophiles in the Pd-catalyzed cross-coupling with tosylhydrazones affording di-, tri-, and tetrasubstituted olefins. Fine tunning of the reaction conditions are required to accomplish the coupling successfully, includin
2,2-(Diaryl)vinylphosphine compound, palladium catalyst thereof, and process for producing arylamine, diaryl, or arylalkyne with the catalyst
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Example 10, (2010/01/31)
A novel 2,2-(diaryl)vinylphosphine compound represented by the following general formula (1): (wherein R1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, etc.; R2, R3, R4, R5, R6, and R7 may be the same or different and each is an alkyl group having 1 to 6 carbon atoms, an alicyclic group having 5 to 7 carbon atoms, etc., provided that R4 and R5 taken together and/or R6 and R7 taken together may represent a fused benzene ring, a substituted fused benzene ring, a trimethylene group, etc.; and p, q, r, and s each is 0 to 5, provided that p+q and r+s each is in the range of from 0 to 5); a palladium-phosphine catalyst obtained by causing a palladium compound to act on the novel 2,2-(diaryl)vinylphosphine compound; and a process for obtaining an arylamine, a diaryl and an arylalkyne in the presence of the palladium-phosphine catalyst.
